Trust in the medical profession is the foundation of effective healthcare systems, directly influencing adult patients’ willingness to seek care, disclose confidential & highly sensitive information, and comply with treatments. Human connections are what builds that trust.

In the NICU it’s a bit different because the first human connections often happen around admission, which is often unexpected, sudden and dramatic. Connections we form in fetal medicine consults are also taking place surrounded by uncertainty and anxiety. Most of the information we need as physicians to plan acute management is gleaned from discussions with midwifery, obstetric & fetal medicine teams, or is available in the maternal notes. Unlike in adult medicine where trust is built on past interactions and public profiles, trust in the NICU team represents an immediate future-oriented acceptance of vulnerability. However, trust rapidly changes during the NICU stay.

^{The amazing & welcoming neonatal team at PGH, Manila. Neonatal care looks very similar in most of the world!}

Most parents have little idea about neonatal medicine and trust is based on the belief that the team will consistently act in the baby’s best interest. Parents have no idea how good we are at tasks like intubation or echo scanning, how experienced we are, or how much we do or do not genuinely care. As someone who worked on the NICU for 35 years, it seems we just expect parents to automatically trust us. We know we’re ‘trustworthy’, why don’t parents?

It’s the little things that count.

My experience over many years tells me that “micro-interactions” are the basis of the relationship and trust that parents form with healthcare staff. It’s the little things, the smile and greeting at the start of the day, remembering the baby’s name, who the partner or other family members are, what are the things that the mother worried about yesterday, how did she get to the NICU this morning. During antenatal consults, do we greet, introduce ourselves, explain what we do and demonstrate ‘active listening’? Or do we just tell parents what’s going to happen, and then let our colleagues know “I updated them, they didn’t seem to have any questions.”

Micro-interactions matter

On the NICU, do we behave in a way that demonstrates we have got time to listen to their questions and we aren’t endlessly busy doing ‘more important things’? If we looked at them rather than checking our pager, if we sat down instead of standing over them. These micro-interactions are vital skills for all healthcare workers, especially nurses and therapists, but it is physicians who parents see as being ultimately responsible for ‘life and death’ decision making on the NICU.

Almost 20 years ago, I was fortunate to start working with fetal medicine specialists and other specialties, as well as sociologists and academics from other disciplines. It opened my eyes, and I never saw the NICU in the same way again. I became fascinated with our body language, the precise words we use, the facial expressions that convey so much to parents without us realising. And I would watch the difference in parents’ expressions when we said things like “he’s had a bad night, we’ve been struggling to get the CO2 down” compared to “he had a CO2 of 9, so we put the MAP up, the CXR is better expanded and the CO2 is now 7.” I’m pretty sure most of my colleagues never realised I always was watching their body language and expressions so intently!

Emotion work in twin loss

Recognition of, and evaluation of, emotion work was an issue raised by all parents in our qualitative studies of baby loss when talking about their interactions with staff, in particular nurses. Mothers placed a high value on their relationships with staff who offered emotional support, and the nature of those relationships had a major impact on parents’ experiences in the hospital.

She [nurse] was really nice, we got a lot of support off her…she was more on our wave length, someone you can sort of feel comfortable talking with’.

Bereaved parents often identified one particular health professional who had acknowledged their bereavement and spent time allowing them to talk about their loss, or simply made time for a friendly chat. This person became a familiar face that mothers felt they could relate to, rely on and trust. Usually they were a nurse and they figured prominently in parent’s accounts. However, whilst parents appreciated any ‘emotion work’ done by physicians, there were many more accounts of ‘less positive’ interactions.

The nurses were very supportive…the doctors I don’t think so much, but only because they do ward rounds and they have to assess what is in front of them there and they are doing such an important thing aren’t they really, that’s kind of not relevant to them.

It seemed like parents had lower expectations of physicians providing emotional support because we had something ‘more important’ to do. In contrast, parents talked about nursing as a ‘vocation’ almost with an expectation that nurses would instinctively recognise the parents’ need for emotional support alongside the formal role of caring for their babies. It doesn’t seem that parents necessarily had the same expectations of medical staff to do emotion work.

I had issues with one of the doctors… because he was like, “oh, she’s not going to make it, oh she’s, do you understand has a blood clot.”

I knew he was doing his job, but I just don’t think that the way they get across bad news to parents is the best.

Nurses who were less emotionally accessible were also perceived as ‘just doing their job’ - caring for the baby but not recognising the emotional needs of the mothers.

they (some of the nurses) can be seen to be like “it’s just a job” you know. Some of them was just like that and just like, ‘it’s just their job’ you know. They come in and they do their job and go.

Staff who provide emotional support are perceived as more competent

Parents perceived the staff who provided emotional support as also more competent at providing the medical care for their baby. Staff who were emotionally remote made parents feel uncertain about leaving the baby in their care. Staff behaviours and unit ‘culture’ had a big impact on how parents felt when they had left the hospital to go home.

Especially on a night shift, I found that was when they [nurses] just didn’t, just didn’t seem to care. They were like…they just go in for a social and I used to come home nervous’.

It’s clear to all of us who work in the NICU, that a balance needed to be struck. There is a tension with views expressed in other literature that a genuine display of emotion is ‘unprofessional’ and potentially detrimental to the standard of care provided to the baby.

Nurses are expected to balance the these views by displaying ‘managed emotions’ which emphasises a ‘display’ of emotion perhaps rather than a deeper, more genuine feeling. If a really sick or dying baby upset us as much as another family member, or a friend, we couldn’t be effective and safe. But of course, it is OK to be upset, and to demonstrate that we care. It has to be authentic though.

How should physicians display emotions?

Like all neonatologists, I have been present in the room when a baby dies, most often in parents’ arms after a shared decision that further active intensive care is not what parents want. It’s a central component of our work. We all train to be neonatologists recognising we will have to do this. It happens a lot; in a large NICU there might be 40-50 neonatal deaths a year.

Most of the babies die peacefully in a private room on the NICU or nearby. Death happens when we remove the endotracheal breathing tube that connects the baby to the ventilator. Typically in the room with the baby are the neonatologist and nurse, the parents, and sometimes other family members. I will write more about how it happens, and what it feels like to be the physician in another article. I will also ask a nurse to write about what it feels like for them (message me!).

I would stay in the room with the parents sometimes for a few minutes but sometimes longer, perhaps 20-30 minutes after removing all life-sustaining support but it is very variable. As we sit there, sometimes next to parents on the sofa, or separately, I am ‘reading’ parents’ body language and cues, and wondering what I feel. Parents are usually focussed looking at the baby, but sometimes they will look at the nurse or me, perhaps for reassurance, or to ask a question. I try to sit still, not fidget, look relaxed but still focussed. I hope my face displays the fact that I genuinely care, but I have never shed a tear in the room. The nurses tend to display more emotion, but not always. It wouldn’t be unusual for some nurses - if they are female - to shed a tear.

There is some non-verbal eye communication with the nurse that helps me work out when it feels appropriate for me to leave the room. I might say, “what do you think if I step out for a while, and give you some time. I’m just outside if you need me, but i’ll pop back in 15 minutes?”

As humans, we are very quick to form opinions of others. Sometimes, that very first interaction that only lasts a few seconds or minutes colours impressions for a lifetime. As we then see people over months and years, our opinions and feelings change and develop. But new NICU parents don’t get that luxury. In an instant they are asked to trust us. To have a meaningful discussion about treatment decisions such as withdrawal of active intensive care, parents need to trust all of us. Micro-interactions matter enormously.

It’s the little things that count.

Also posted here on Substack.

To find out why people feel a twin pregnancy is special, we need to speak to them.

I was excited…I felt, how can I put it…I felt special. I felt special to be carrying two babies, you know, I really wanted my two babies who, I seen two babies on that scan, I wanted two babies

How did we do the research?

Thematic analysis takes a large dataset - in our case from audio-recorded interview recordings with parents - that are then transcribed and reviewed by researchers to familiarise themselves. Data collection (interviews) continue until the researcher feels they are reaching “thematic saturation” - where parents are saying similar things and no new findings are emerging. Typically, this takes between 5-20 interviews depending on the diversity that exists - people (age, identity, profession), topic, intensity of emotions generated (e.g. baby loss versus parking problems), variation in experience (e.g. miscarriage, neonatal death etc.)

Researchers then generate initial codes (phrases, words or sentences e.g. sadness, anxiety, work, children going to school), and then group these codes into broader meaningful categories (mental health, family relationships) as structured findings and themes. This is often led by 1-2 researchers, although the wider research group will contribute.

Findings (themes) can then be validated by sharing them with others e.g. other bereaved parents at workshops. The analysis highlights similarities, differences, and unexpected insights across a dataset. Qualitative analysis can have a huge impact on both neonatal morbidities and long-term parental trauma-informed care but is often “looked down” upon especially by physicians who don’t understand research studies without p values and confidence intervals. However, those physicians should also recognise that most p values make no difference to clinical care, and most conclusions are false or biased.

I digress.

We spoke with 14 mothers with a multiple pregnancy where one twin had died during pregnancy or in the neonatal period, between 6-24 months after the loss. Fathers or grandparents were present in half the interviews, and the surviving sibling present in most. Our analysis identified three main themes - 1) status as special, 2) trust and 3) control & empowerment. Here we will focus on the first theme.

Feeling special

Mothers often spoke of feeling ‘special’ when they discovered that they were expecting twins. The unexpected loss of one baby was devastating and parents grieved both the loss of the baby, and the loss of their ‘special status’. Where surviving babies were being cared for in the hospital, parents had to deal with their grief, alongside their joy for the other baby/s and their fears that the surviving baby might die.

What I got a lot of… the doctor at the time really quite upset me… she often said to me, ‘At least you’ve still got one’ , and that was one of the worst things that anyone could possibly say. ‘You’ve still got [surviving twin] though’ and I know I’m really grateful I still have [surviving twin] but that’s like saying to someone that has a child of four and six and the six year old one dies, ‘well you’ve still got the other one, so that’s ok’. And it was really quite upsetting. I knew that she didn’t mean it in any nasty way.

Parents appreciated healthcare professionals (HCP) who tried to maintain the special twin identity on the NICU. But many HCPs didn’t recognise the twin identity. I remember before we did the Butterfly project feeling really uncertain about what to say or do. Should I keep mentioning the twin status or just quietly let it slip away? It felt a bit awkward, and maybe we thought we might upset parents if we mentioned it again. Parents probably took that as indication that we didn’t care.

Baby names

A baby’s name gives them their identity. Parents will often (but not always) give their babies names during the pregnancy. When a twin died on the NICU, we often forgot the name, or didn’t ever know it perhaps. I was always scared I would get the names of the babies mixed up if one died.

One of the nurses that was least conscientious towards other people’s feelings kept calling him [surviving twin] by his brother’s name afterwards

Some of the nurses would encourage parents to place a photo of the baby who died into the incubator of the surviving twin, even better if there was a photo of both of them together. Sometimes it was an antenatal scan. Sadly, many parents had no photos of both their babies together.

Trauma and grief on hold

Most mother’s described a rollercoaster of emotions whilst in hospital with the surviving twin.

Parents talked of a juxtaposition of feelings of simultaneous joy and grief, but in the period immediately following the loss, they overwhelmingly talked of feeling traumatised.

I think I totally switched off looking back now, from the moment I got back to the hospital, I think I just went into autopilot…yes, this is not happening, because there were no tears or anything was there? Nothing at all for days’.

Mother’s talked about the need to keep their emotions ‘on hold’ and described strong grief reactions that emerged weeks, months or years later. In some cases mothers talked about putting feelings on hold in order to be strong for the surviving baby.

We saw her [deceased twin] for some time after losing her and then our focus to help us get through, it was wanting to be out of hospital…and went up to [other hospital] to be with [surviving twin]. That was giving us some strength…being there for him

^{There was often nothing to see that demonstrated the twin identity, and many staff cared for babies without even realising they had a brother or sister who had died.}

Many felt it was too soon to see counsellors or psychologists whilst they were on the NICU - many waited a few weeks or months, but I know other parents (and surviving twins) have felt they would benefit from counselling years or decades later.

It was about six months…we went for bereavement counselling…I was suddenly feeling so bad…really angry’.

Feeling ‘special’ or ‘different’ was common during the pregnancy and continued throughout their lives. Parent experiences of care in the NICU whilst supportive, seemed to reinforce that sense of difference, in terms of how their contradictory feelings were accommodated, and the ways in which their grieving did not seem to fit with the usual offers of support.

Twin identity is very strong. Most “twinless twins” feel a strong sense of their brother or sister throughout their lives. Some describe “living life for two” or living life in a way that honours and respects their twin. But many parents I’ve spoken with struggle to know how to maintain the special twin identity. And many twin survivors are uncertain how to make sense of it all.

Great if you can share these posts with anyone you think might be interested. I am not after ‘likes’ - I am interested in connecting with others, and helping give voice to the parents’ experiences to improve understanding and care for future families. Thanks for reading to the end! Have a great day.

^{Gigi’s book is available on Amazon and is a great read. Gigi is a bereaved mum of twins and I’m asking her to write an article at some stage (thanks Gigi!).}

Also posted here on Substack.

We don’t want adult sized toddlers, right?!

Breastmilk alone cannot meet protein needs of very preterm infants on the NICU, although high volume feeds and other supplements may ameliorate some of the growth faltering we commonly observe. We’ll discuss approaches in another post.

Energy needs are dramatic. Using different theoretical approaches, most estimates are that total energy requirements in preterm infants are around 120kcal/kg/day on average. Compare this to Colombian cycling legend Egan Bernal who won the Tour de France in 2019. He weighs around 60-70kg and during ‘le Tour’ consumes around 6,000-7,000 Kcal/day. Imagine how wonderful it would be to consume that many calories without getting fat?

If you estimate energy requirements you can see that very preterm infants need more energy, than the energy required to cycle up and down mountains. Some of that energy in preterm infants is expended in wriggling about, but that only accounts for a small fraction. A small amount of energy is also expended in heat production - more if you don’t keep them warm with KMC or incubators.

Most of the energy is ‘used’ in two ways

(1) being converted into energy stored in tissues (fat, protein, glycogen etc.) or,

(2) accounted for by the energy consumed by “Basal Metabolic Rate”, or BMR.

BMR is effectively the energy required to run all your vital functions and cellular systems at rest, including brain, cardiac and respiratory activity, sodium/potassium pumps in every cell, hepatic production of proteins etc. BMR actually doesn’t vary that much during the NICU stay - it’s around 50kcal/kg/day. Heat production and activity are around 5-10kcal/kg each per day, meaning there’s around 50kcal/kg/day remaining to be stored as protein and fat.

BMR doesn’t really alter (except during acute illness when it’s not by definition ‘basal’), nor can you stop babies moving, breathing, heart pumping or trying to keep potassium inside their cells. That all takes around 60-70kcal. Simple maths will show you that giving 100kcal/kg/day, which sounds like a good amount, means you’re only making 30kcal available for tissue deposition. A seemingly small deficit of 20kcal.

The problem is that the ‘first’ 70kcal you give has to go to BMR (and movement and heat.) You are then only meeting 60% (30/50) of the energy needed for growth. Growth faltering is pretty common even when you think you’re doing a good job. Which of us could maintain our weight on 60% of predicated needs? _{Though there are a few who could risk giving it a go.}

Failing to give enough macronutrients to a preterm infants is also very common and often avoidable; seriously, why would you not give enough? And if body growth is slow, maybe brain growth is also slow, and maybe some of the long-term neuro-cognitive sequelae of preterm birth are more common… It’s difficult to see how any of this can be good, despite a few sceptics telling us not to worry about growth, and the experts who tell us there’s nothing more dangerous than an expert.

Human brains are massive

It is the human brain that distinguishes us from every other mammal including other primates. It is huge and it requires lots of energy to develop and function. Throughout pregnancy neurones formed in one part of the body need to migrate to their final destinations (NEURONAL MIGRATION) ready to perform critical brain functions.

At birth babies have all the neurones they will ever need - about 100 billion. But, they are not wired together very well, and that process of SYNAPTOGENESIS takes a huge amount of energy over the next 2 years. In the first few postnatal months, babies form 1,000,000 synapses per second! If we gave a term infant 40% less energy I expect he would have to down-regulate synaptogenesis. If you are not impressed by that stat feel free to unsubscribe and watch England lose on penalties to Germany. Synaptogenesis is especially active in the visual and auditory cortex of course. We can see it coming.

_{We can discuss apoptosis, synaptic pruning and myelination in other posts.}

Although it is difficult to precisely measure, it seems that about 50-60% of energy expenditure in healthy newborn infants over the first months is the brain. Growth has slowed from fetal life, thankfully, and diets have low protein but energy demands are high. Whilst protein seems to dominate nutrient requirements as a preterm infant on the NICU, after term age ENERGY becomes most important, and all efforts focus on this. Lots of lipids, lactose in milk, and just enough protein to form the cells and support slow growth.

As adults, the brain represents about 20-25% of energy expenditure but we do not know what % it is for preterm infants. Synaptogenesis is starting slowly in the second and third trimester, and whilst I used to think the brain might represent 50% of all energy in preterm infants, I suspect the true figure is much less, as proportionately more of the energy is needed for lean mass accretion. Maybe it’s only 20-25%, who knows? Either way, it’s significant, and failing to meet energy needs, or observing growth faltering must cause concern about the adequacy of macronutrient supply for the brain.

Brain growth and differentiation is so complex we won’t ever understand it. We would need an even bigger brain to understand it, which would then be even more complex to understand … catch 22. What we do know, is that these processes are under the control of multiple hormones, especially IGF-1 (Insulin like growth factor 1). IGF-1 concentrations ex-utero are pretty dismal compared to in-utero (50-80% lower), and whilst some companies are investing millions into trials of synthetic supplemental IGF-1 the data to date are underwhelming. There is however, some evidence that macronutrient intakes (energy and protein) modulate IGF-1 concentrations providing a potential mechanistic link between diet and brain differentiation and growth.

Back to breastmilk.

Mother’s own milk, especially fresh (i.e. warm), is life-saving for premature infants and the most cost-effective in all of medicine.

Prove me wrong. All medicine, not just neonatal. Donated human milk has lost many of it’s functional benefits through storage, pasteurisation and transport, but is still associated with lower rates of NEC even though it doesn’t seem to reduce surgical NEC or mortality (another post needed there). This might be because although heat permanently alters protein structures (antibodies etc.) it has much less effect on small sugars (HMOs) which may be a key component in reducing NEC risk.

Human milk with <1g/100mL will never meet protein requirements in extremely preterm infants. But for energy, the equation differs. Human milk has around 65kcal/100mL albeit with substantial variation between individuals and stage of expression, and usually much lower in DHM. This means that feeding MOM at 180-200ml/kg/day will meet energy needs in most very preterm infants (but won’t meet micronutrient, mineral, vitamins needs etc.) DHM at 200ml/kg/day won’t meet needs.

Protein is the problem. Preterm babies need more protein than from MOM alone. If energy was the problem, we could solve it more easily.

Where can we get more protein?

We’re surrounded by a key element for the diet, nitrogen. Preterm babies breathe more nitrogen in and out than oxygen, and have at their finger tips (well alveoli) the core element for building amino acids. Why don’t they wake up, smell the coffee and use it? Caffeine citrate is, of course, odourless which might be part of the problem.

Nitrogen is the core element of amino acids, amino acids make proteins, and proteins make prizes … but humans (like all mammals) are incapable of turning atmospheric nitrogen into amino acids. Nature didn’t think it necessary. Shame. How disappointing to watch a sick preterm infants on a ventilator, being given all the nitrogen it could dream off, being ‘expirated’ 0.3 seconds later before it could be fixed.

We need plants or insects which animals can eat, which we can then eat, or consume their milk. Theoretically, we could get extra protein from non-animal sources (seaweed, plants, bioreactor bacterial synthesising proteins) but that won’t be available this decade (but I am predicting that next decade milk-identical protein will come from a bioreactor). As of 2026, the protein preterm babies need has to come from another animal, and whether you like it or not that’s going to be a cow in the global majority. I could though write another post on human milk-protein-derived products if you want?

Please subscribe to these posts and the Baby Loss posts from the Butterfly project. Some of the email sign-ups end up in junk mail folders so check there. Feel free to comment and spread the word. I’m open to questions, but can’t promise to answer them.

Also posted here on Substack.

PParents who had a multiple pregnancy where one or more babies died, but where one (or more) babies survive, face unique challenges. Our research identified many themes - mostly centred around acknowledgment.

Acknowledgement that

• this was/is a multiple pregnancy

• a baby died - and most often had a name (and not “twin 2”, or a “9-week fetal loss”)

• there is a juxtaposition of grief for the baby/s who died, alongside hope and fears and joy for the baby who is surviving

• challenges are not better or worse than a singleton loss, but they are different

‘one of the doctors at the time really quite upset me and she often said to me “at least you’ve still got one” … that was one of the worst things that anyone could possibly say’

Every parent we have ever spoken to has been told “at least you’ve still got one”. They are told it by friends and family, by nurses, doctors, midwives. Everyone. Even decades later.

I can, perhaps, understand why some people might say it without thought, but when challenged to reflect, most people can see how hurtful that statement must be. If the loss occurred early in the pregnancy, many parents were encouraged to no longer consider it a twin pregnancy and were told ‘just think about it as a singleton pregnancy’.

With many families from decades ago, the baby who died was never mentioned again, and some parents (and living twins) didn’t even know where the baby was even buried. They were discouraged from giving that baby a name and many hid their grief for a lifetime. Surviving twins who found out they were a surviving twin when they were adolescents, sometimes asked their parents’ permission to give their twin a name.

Continuity & connection

On the neonatal unit (or postnatal wards) we often made things worse. We might forget the surviving baby is a twin, or that parents were struggling with the juxtaposition of loss and hope & joy. Parents, quite rightly, expect that healthcare staff know what happened. We should know what happened, when and how, and the baby’s name. Parents didn’t like having to retell the painful story they felt we should already have known. But they often valued the opportunity to share their story again, often with the bedside nurse. They wanted a chance to tell us his/her name, how much they loved him, how much he meant and how proud they were of his short life.

We are usually quite good at ‘handing over’ medical information about the baby (ventilator settings, medications, scan results, management plans etc.) but we are not so good about handing over the emotions parents share with us; their fears, hopes, uncertainties. Many writers have discussed the important sense of the ‘connection’ that patients, clients or parents have with their ‘provider’. This sense of connection is vital to building trust and makes a big difference to parents’ sense of wellbeing. How could parents trust us if we didn’t even remember there was another baby who had died? Sadly, for many families of premature babies, or those with short lives, healthcare staff may be one of the few people who met their baby alive as friends and family weren’t able to meet them. We hold a special place in those families’ hearts. They may not remember what we said to them, but they never forget how we made them feel (Maya Angelou).

Who’s looking after him tonight?

Most parents do not stay on the NICU 24/7 - unless they are fortunate enough to have childcare at home, financial stability and be in a hospital with single rooms. But parents like to know who is looking after their baby when they are not there. They will often ring the unit last thing before they go to sleep and ask ‘which nurse is looking after my baby tonight’. If they know (and trust) that nurse, they may sleep easy for a few hours. But if they don’t know the nurse by name, they often struggle to sleep, or might ring back after a few hours to check all is well.

Cot spaces and loss

Every neonatal unit is busy; sometimes it feels like it’s “one out, one in” on a shift. When we admit twins, we try to place them in incubators that are next to each other but sometimes that isn’t possible. But when a twin baby dies, parents often have to witness the heart-breaking admission of a baby into the cot space where their baby had died, perhaps just a few hours or day earlier.

We often have no choice, and the parents of the newly admitted baby of course have no idea either what just transpired. What must it feel like to have sat between two incubators reaching out to both your twin babies at the same time, and then after one dies, just sit and look at your surviving twin? Telling parents we recognise how hard that might be, shows parents we care, even if we can’t solve the problem. If possible, the nurses will offer to move the surviving twin into the cot space that was occupied by the twin who died. If that is what parents want. To know what parents want, we have to share options and ask them. We cannot second guess.

“I know what you are going through”.

Actually, most of us probably don’t. We might have years of experience of caring for parents experiencing loss, read literature and attended training days, and we might have our own experiences of loss. Many of us do. Most often though, we don’t know what these parents really feel. But parents do gain comfort from knowing they are not alone, and that others may have experienced similar challenges. Many, but not all, parents benefit from psychological support. Peer-support can be vital and life saving. Groups that offer this, or when parents manage to connect with other families who have similar experiences, can have a lifelong impact.

Also posted here on Substack.

Breastmilk is more than food

Human milk has lowest protein concentration of all mammals on the planet

Human breastmilk has lowest concentration of protein, just under 1g/100mL on average. It is a little higher 1.5-2g/100mL in the first few days, but at this stage lactational volumes are much lower and the protein concentrations decrease in most women (even those delivering preterm) to around 1g/100mL by 1-2 weeks of age, and sometimes lower. The protein content in Orangutans is slightly higher - perhaps 1.2g, but human milk has a concentration less than 1/3 of the protein of cow milk (3.2g-3.5g). And compared to many marine mammals, human milk contains only 1/10th the amount of protein (whales and seals 12-14g/100mL) but this is still lower than a cotton-tail rabbit (14g/100ml).

Protein is the essence of life, and is needed to support growth. When growth is slower, less protein is needed. A rabbit doubles its birthweight in under a week, a calf takes just over a month, but human babies take around 6 months to double weight. Orangutans also grow slowly - they also breastfeed for longest, 6-8 years by some accounts and stay close to their mother’s sides for much of this. A newborn calf has to stand on it’s own four legs within hours of birth, and like many other mammals needs to be able to evade predators soon after birth to stop being food for some other mammal. Seal pups are vulnerable to predators in the sea or ice; certain species grow at unbelievable rates - the hooded seal only breastfeeds for 4 days.

Humans and big brains

These differences between humans and calves, are explained by the complexity of human brain development and the complexities of our social environments - the two are, of course, inextricably linked. Although the brains and breastmilk of other primates are similar, most mammals are nothing like humans. It is the reason you are reading this on a phone instead of spending all day searching for fruit like an orangutan.

Rhinos have huge heads, but most is fresh air in sinuses, compared to humans where the brain fills the entire cranial cavity. The figure on the right below shows body weight on the X-axis, and brain weight on the Y-axis (both on a logarithmic scale so it fits on the page). Proportionately you can see shrews, dogs and rhinos all plot close to the average line. But human brains are off the scale - 10-20x as big as most mammals proportionately.

Human’s have massive brains, and around 85-90% of the final adult volume is acquired in the period between 24 weeks gestation and 2 years of life - most of the first “1000 days”. Nutrition and growth in this period determines your cognitive function, lifelong metabolic health, whether you will get type 2 diabetes, or die of a heart attack. Slow growth gives humans the time needed to learn the complex rules of social interaction. It takes around 15-20 years to learn adult behaviours, and recent societal changes show ‘parenting’ continues into the 20’s. Fast growth (like most other non-primate mammals) would be a disaster. We’d have 5 year olds the size of adults.

What appears to be ‘low’ protein concentration in breastmilk is actually ‘normal’ and perfectly adapted to slow infant growth in healthy, term newborns. During these first 1000 days the body grows slowly, but the brain grows rapidly. Whilst low protein concentration is ideal, massive amounts of energy are needed to support synaptogenesis (brain wiring) and explains in part why humans are the fattest mammals in early infancy. Whilst human fetuses also require high energy intakes, they also need high protein intakes provided by massive trans-placental amino acid transport especially after 24 weeks. Human milk doesn’t replicate these needs. Human mother’s own milk, warm and recently expressed, is life-saving for preterm infants, and also results in the best longer term cognitive and metabolic outcomes. But at 1g/100mL protein, it will fail to meet protein needs for ELBW even when fed at 200ml/kg/day. This is one of the key challenges we face in neonatal medicine.

My aim in writing these posts is to improve understanding and create a global community where we can share ideas, knowledge and insights to improve nutrition and growth especially in resource limited countries. Thank you for reading. Please share with your networks and like-minded friends. The next few posts will cover more topics around early growth and breastmilk composition, and we will start to un-pick the challenges we face. After that, I’d like your ideas as to practical solutions.

Also posted here on Substack.

More than 15 years ago I started working with a team to explore parent feelings and experiences about the time when the NICU team felt it appropriate to discuss the option of withdrawing/stopping active intensive care for their sick baby. The research ethics committee were hesitant suggesting that we might upset parents if we reminded them their baby had died …

I found the research experience deeply humbling on many levels, and I learned much more in that study than I expected. I learned from academics in other disciplines, but most importantly from parents. We spoke with around 15-20 families, and a similar number of NICU staff. I thought we might end up focussing on themes around communication, or practical aspects of end-of-life care, or perhaps the morals, and ‘rights and wrongs’ of withdrawing life-sustaining support. However, most importantly I learned to listen to other peoples’ stories and the meaning of life.

I quickly came to realise that the NICU doesn’t exist in a vacuum, and became fascinated with parents’ stories, and the reflections of staff. To my shame we still haven’t got that paper published. It was rejected by two ‘decent’ journals, and even the abstract was rejected from a large paediatric meeting (PAS/AAP) that usually accepted pretty much everything!

During the parent interviews we noted that 3 families had premature twins where one had died, but one had survived. This was a challenge/situation that I and many others had observed as doctors and nurses on the NICU but tended to ignore. Everyone, pretty much, is fascinated by twins and triplets - how similar or different they are, and whether any differences are due to the environment and parenting or their genes. There are films and documentaries about twins, they feature regularly in social media and they are often subjects of scientific study to determine heritability.

If you haven’t seen it, check out the film “Three Identical Strangers” - which used to be available on Netflix. A very sad and moving story, and one of those most powerful films I have ever seen. Identical triplets put up for adoption in the early 1960s, and deliberately placed with three separate families who had no idea they were not singletons, in what can only be described as a cruel psychological experiment. They were studied without realising they were part of an experiment. Shockingly, some of the research ‘data’ has never been made available. It gives you an idea of the importance of love and connection when you’re growing up.

Elvis Presley was a twin whose brother was stillborn just half hour before him. Elvis’ mother apparently commented that one of Elvis’ driving motivations in life was to try and connect with Jesse. Interestingly, Elvis was encouraged by Liberace to be a showman; Liberace was also a twin whose brother died at birth. These were two of the most flamboyant characters in the 1960s and 1970s - how did their identity as twins (what some would call twinless twins or lone twins) shape their life and behaviour?

And more recently Georgina Rodriguez and Cristiano Ronaldo had to share the sad news that one of their twins had died shortly before birth. They and their other children grow up with the world watching their lives evolve.

Our first research studies taught me a lot, and I noted [on the NICU] that there was a tendency not to talk about the twin who died, or acknowledge the surviving baby was (and still is) a twin. We rarely mentioned that twin again, forgot his name, didn’t acknowledge him/her in the NICU discharge letter, or when they came back to follow up appointments. A lot of the time we didn’t know what to say. Sometimes I would return to clinical service after having been on leave, and no one told me that the baby on the ventilator in cot 5 had a twin who died 10 days ago. This made the parents’ grief more challenging and sad, and probably made the parents feel that we didn’t care.

This led us to conduct a further qualitative study with the parents of multiple pregnancies where one baby had died, and at least one baby had survived. The baby loss may have been a miscarriage, stillbirth or neonatal death. We included pregnancies where the baby may have died following medical intervention e.g. a termination, or following assisted reproductive techniques (“IVF”) and included triplets as well as twins. Most often though, they were prematurely born twins. In some cases parents knew during the pregnancy that one of the babies might die if they had a serious genetic anomaly associated with a short life; in others, such as extremely preterm birth parents suddenly found themselves thrust into the trauma of the NICU, scared that one or both of their babies might not survive.

We analysed the findings using standard qualitative methods (thematic analysis) and then shared the results at workshops with other healthcare professionals, and with other bereaved parents. It was at one of these workshops that a parent remarked “…just put a little blue butterfly on the cot of the survivor, and everyone will know he was a twin”. A lightbulb went off, and I immediately discussed the idea with some of the nurses and we decided to make the butterfly purple-coloured to avoid any boy/girl connotations with blue/pink. I also recognised the importance of remembering the baby’s name. More than once, I had called the surviving baby by his deceased brother’s name, but more importantly, using the name made this personal for the families. We encouraged the parents to write the name - we used waterproof pens so it wouldn’t rub off with the humidity or cleaning wipes. Simply writing the name appeared to carry immense meaning for parents. Millie from the Skye High Foundation (named in honour of her twin baby Skye who died) had a similar idea and we have worked together for more than 10 years now sharing this project. I’ll ask her to share her story in a later post.

The Butterfly project has spread to 100’s hospitals in many countries around the world. We made all the resources free to download so the truth is we have no idea which hospitals use it. It would be nice to know where, but it doesn’t really matter.

In the next post, I’d like to share some of the themes that came from the research. Please share links with friends and feel free to share your opinions, insights and experience. thanks.

Also posted here on Substack.

I qualified MBBS 1990, started paediatrics 1991, & did my first NICU job 1992. I was utterly terrified those first few weeks, but worked with some brilliant nurses who looked after me, and an inspirational consultant Edmund Hey - one of the pioneers of neonatology (seminal work on resuscitation and thermal management in the 1960s!). We worked long hours as SHOs (residents) - 24 hours on, 24 hours off, for 2 weeks, knew the babies and families inside out, and then 5 daytime shifts and a whole weekend free 1:3!

Such was neonatology at the time, that within 4 weeks of residency starting we had all learned to intubate and drip most babies and the fear subsided. I remained a bit scared of the nurses (still am), and always a bit uncertain what to say to parents. Surfactant was becoming routine but antenatal steroid administration was inconsistent, so lots of RDS, a Bourns ventilator that sat on top of the incubator, but with no graphics. We got good at transillumination and chest drains.

Ed was non-interventional so we rarely did art lines or PICCs, and a strict protocol of always doing what the nurses told us. The maternity hospital was a mile away from the City’s main hospital, so had our own lab for measuring serum sodium, bilirubin & osmolality. Lots of exchange transfusions for Rhesus. Busy busy. Great fun.

I was a bit disappointed when, as a registrar (senior resident), I realised I loved neonatology, as my intention had always been to be a General Paediatrician but my borderline ADHD/ASD/INTJ-ness had other plans. I became interested in research, and under Ed’s mentorship I wrote papers on Edward’s syndrome and Group B strep - Ed’s mantra was always to write papers you’d be proud of in 10 years time. They were well cited. I wept when he died unexpectedly in 2009, which took me by surprise as I never realised how much he had meant to me and had to creep out the back of the church funeral so no one saw me. By then I had a moderately successful research interest in nutrition and growth, started planning some big RCTs, and loved my clinical job especially the acute, technical life saving whooshy whooshy echo machines and number stuff. I’ll post another time on why doctors want to be a hero. Just possibly also including me. And why wanting to be a hero can change your attitude and behaviour.

At about the same time, 2007/2008, I had a chance meeting with a Ruth, social scientist, Judith, a maternal epidemiologist and Steve, a fetal medicine Prof. They were conducting qualitative work and exploring women’s feelings and experiences of being offered termination of pregnancy, and the option of feticide prior to delivery. Important and heavy. They asked me “how do you think parents feel when you ask them to agree/consent to withdrawal of active intensive care”. We planned and got funding for a qual study where an RA spoke to several bereaved parents, and the staff who cared for them, including me. I was humbled by how little I knew about sociology, psychology and qualitative work, but it changed me personally, my career, and how I behaved.

I questioned my personal and professional identity. Are they one and the same? Do you ever stop thinking you’re a neonatologist or neonatal nurse? I questioned why I went to some baby’s funerals, but not others. Did that mean I didn’t care about them as much? After we removed an ET tube, and we sat with parents as the baby passed away, why was it OK for the nurse to cry, but I never felt I should. I would though, sometimes take myself for a ‘lazy wee’ if I felt upset as the washroom stalls were the only place you could get a bit of privacy for a few minutes? [OK, it’s toilet but I’m being inclusive of any north American readers.] My kids would ask me (after I had rushed from the house to tube a baby) “Daddy, did the baby die?” and I always lied and said, no, he’s fine now. I felt bad that children should have to know that babies died. How could I sit with parents, watch the baby slowly become apneic, confirm absent heart sounds, and then get up and meet my colleagues for lunch and laugh about the soccer. Did that make me a psychopath? And how could you find so much reward and enjoyment in looking after a baby so sick he might die.

Is it OK to be facebook friends with a parent whose baby died? How long do you have to wait before accepting the request. What do the brothers and sisters think when they’re told their much anticipated baby brother died. What do you feel as a surviving twin when your brother died at a day of age before you ever remembered his face. Do you tell your friends at school you’re a twin. When you see a parent from years back walking towards you down the street, and you can’t you remember if the baby survived? “Hi, um, how are things going?”

So genuinely, no one is more surprised than I am, that having been fascinated by the epigenetic correlates of rapid infant growth, I am so interested in feelings and experiences. I didn’t become a neonatologist to do that. Almost the opposite of that? But I gradually became fascinated about how we interact with each other, interact with parents, the furrowed brows and sucking of teeth when a baby is sick. I watched parents hang on to every word and facial expression of the attending consultant. Sometimes I wondered if one consultant made things out to be much worse than they were, so he could look more heroic when he made the baby better. Another consultant telling parents everything would be fine as they slowly became bradycardic. I listened to parents ask if they were allowed to stop one of the consultants from turning the machine off, as they feared that’s what we would decide would happen if they went home from the NICU. Watched parents melt when the nurse on rounds say “he’s had a bad night, his gas is terrible”.

And what actually really matters? All those RCTs to see if we can improved the BSID by a few points but that really tell you very little about future life and joy and love. Sadly, we can’t put a number on the importance of ‘meaning’, but maybe that’s a good thing. It took me a while to appreciate that short lives can have immense meaning. Even a life as a twin just a few weeks after conception.

There’s something deeply profound and existential about baby loss. I don’t want to make out that neonatal medicine is somehow more important or honourable than other branches. But babies are the most cherished of all beings in society. They’re not supposed to be born early, or get sick and die. Pretty much everyone loves them. We’re even happy to be smeared in their faeces or vomit or blood, awwww he’s just a baby, but smear me with an adult’s sputum and I want to barf.

And we all feel terribly uncomfortable and awkward when a baby dies, and don’t know what to say sometimes, so we avoid the topic or become all professional and detached. Residents often ask me, I don’t know what to say to parents when a baby dies, it’s just really sad. You could just say that, I suggest.

We try not to mention the baby who died. We forget their names. We dehumanise the babies, and talk about a fetus with Trisomy 18, and not Rita. And in all of this, we forget that the micro-interactions we have with parents all day long that determine whether they trust us and feel supported. Did we smile and say hello, ask them how they were, or what they were worried about today. Did we remember their name, the name of the twin who died, and act as if we had plenty of time to talk. Or did we make out we were terribly busy and important, that we know best, or we somehow magically know what they are going through, because we’ve seen it before. I think we all really care, but sometimes we could show it better.

It’s the little things that count.

Also posted here on Substack.

Credit to CNN 2023 for the photo - you’ll need to read the follow up post to understand the meaning of this photo!

In my first post, I discussed the question about whether it’s possible for a sub-1250g baby to grow on breastmilk alone. This is important for resource limited settings where access to PN and nutritional supplements is limited or absent.

The nutritional needs of preterm infants are complex, and they need more nutrients per kg than infants born full term. This is especially true for macronutrients (protein, fat and carbs) and micronutrients such as vitamins, electrolytes, and minerals, and trace elements such as iron, manganese and zinc etc. Given their rapid growth rates, limited stores and excess demands (illness etc.) it isn’t surprising they have high nutrient needs. Defining what is an optimal intake is challenging.

In-utero growth and the placenta

In-utero growth is supported by nutrients transported across the placenta. Lots of glucose and amino acids (to make protein) and essential fatty acids, but relatively lower amounts of total fat compared to life ex-utero. As with all mammals, placental transport is perfectly evolved to ensure optimal growth in an environment that is more hypoxic than postnatal life. Large amounts of amino acids are transported across the placenta, and nitrogenous waste products passed back to the mother for her liver and kidneys to detoxify and excrete. Uterine blood flow is around 500 litres/day in the 2nd trimester and >1000 litres/day in the 3rd trimester, most of which goes through the placental inter-villous space from where nutrients can pass into the fetal circulation.

Int. J. Mol. Sci. 2014, 15(9), 16153-16185; https://doi.org/10.3390/ijms150916153

The concentration of essential nutrients like amino acids and minerals in uterine blood therefore doesn’t need to be that high, as the absolute amount that could potentially be provided at those blood flow volumes even with low concentrations is immense. Minerals such as calcium and phosphate precipitate in solutions when the concentration gets too high, but high uterine blood flows solves that problem. When you are restricted to just a total fluid intake of 150ml/kg/day there are challenges everywhere you look to concentrate the solution and provide the optimal balance. We can never provide enough mineral via PN, and we need to get the amino acid composition just right. Enough to grow, but not so high you place a strain on metabolism (autophagy), renal function, and nitrogen excretion. How do we replicate placental nutrient transport when we use PN or start feeds?

Body composition of the reference fetus

Studies conducted in the 1970s and 1980s used the factorial method which estimated body composition (fat, minerals, protein etc.) at different weeks of [fetal] development, then used subtraction to work out how much of that nutrient was accreted between one week and the next. When you do this for protein you come up with a figure of around 2g/kg/day. However, simply supplying that amount will not lead to growth as there are metabolic inefficiencies and losses. You can’t convert 2g of dietary protein (breastmilk protein or amino acids in PN) into 2g of muscle protein (or liver protein) as it has to be digested, broken down, transported to the liver (as peptides and amino acids), metabolised and then reformed into muscle protein. The amino acid composition of muscle will differ from that of breastmilk protein. There is also continual re-modelling of body proteins even when you are not growing - like you and me. This results in an inevitable loss of ‘protein’ as nitrogenous compounds in the urine (urea) and stool. Several billion gut epithelial cells are lost every day (the whole gut lining is replaced every 6-7 days). All of these losses and inefficiencies add up to around 1.5g protein equivalent, which is why 3.5g/kg/day seems to be the minimum intake for most very preterm infants to grow.

Body composition studies provide a fascinating insight into fetal growth. These early studies show that only 1-2% of body weight is due to mineral in bone, and this is fairly constant over the 3rd trimester. Lipid stores are virtually absent at 24 weeks, although there are lipids in all cell membranes especially neurones, brain tissue and the retina. By 40 weeks, fat content is around 13-14% and double this - 25-30% - by 3 months of age. Protein is fairly constant at 10-12%. If you do the math, you’ll see that most of the weight of a 500g baby is actually just water, so when you care for a 24 week infant, remember there’s only 50g of dry tissue.

Parenteral Nutrition (PN) & the shrinking baby

In parenteral nutrition (PN) solutions there is no protein, just amino acids (essential and non-essential) but we talk about ‘protein’ as it makes it simpler to inter-convert. Because PN does not involve gut (splanchnic) metabolism, losses are lower than enteral, and an intake of 3-3.5g/kg/day is usually enough. With enteral nutrition, studies show that lean mass accretion (lean mass is pretty much everything that isn’t fat) is optimal at around 3.5-4g/kg/day, although some extremely preterm infants may need a little more, perhaps up to 4.5g/kg/day.

https://www.sfnmjournal.com/article/S1744-165X(25)00029-0/fulltext

PN is an essential component of preterm NICU care in high-resource settings, but is unavailable in much of Africa, and other low-income settings. If a baby is not receiving enteral milk in those settings, it is impossible to grow. Furthermore, because of the inevitable recycling of protein, there is still ongoing protein (nitrogen) loss meaning a baby receiving no PN will not simply stay the same weight, but will in fact, shrink. Even when you think you are doing a good job and giving a little PN, if you are only giving 1-2g/kg/day (a good amount to start at) the baby, in all likelihood, is still shrinking.

Why extremely low birthweight babies don’t grow optimally on un-fortified breastmilk

Assuming an ELBW infant needs around 4g/kg/day protein from enteral sources, the question is, how much can they get from breastmilk. Breastmilk protein of course is the highest quality. Quality means the extent to which the amino acid profile meets needs. Highest quality for breastmilk when casein and whey proteins are considered together, a little lower quality for amino acids in PN, and it would be low quality if we used vegetable protein (which of course, we wouldn't). The real challenge though is quantity - the concentration of protein in most Mothers Own Milk (MOM) after the first few days (when lactation reaches ‘full’ volume) is only around 1g/100mL. In donor human milk (DHM) it may be lower (around 0.8g) although there is considerable variability. If MOM is fed at 200ml/kg/day an ELBW may still only get around 50-60% of what they need to grow optimally. It is possible to add extra calories using supplements (MCT, olive oil etc.) and extra minerals, sodium etc. but protein is challenging as it has to come from another animal.

Greek protein only just meets essential needs

Protein comes from the Greek meaning the ‘first order’ - the primary, most important constituent of life. No protein, no life. Given how rapidly infants seem to grow, and the primary importance of protein, why is the amount in breastmilk apparently low? Term-born infants need less protein per kg than preterm, up to 1.5g/kg/day. This means that breastmilk (1g/100mL) meets most healthy term infants perfectly if they drink around 120-150ml/kg/day - but there seems to be no room for error! No spare capacity. And the amount of protein the mother eats makes no difference to the protein content of milk. Nature is very conservative. No wastage. Interestingly, a significant proportion (perhaps 15%) of the nitrogen in breastmilk is from urea. This can be metabolised by gut bacteria (especially certain Bifidobacteria spp), and converted into amino acids providing nutrients for infant growth.

A likely reason that protein is so low comes from understanding infant and child development in complex society. Growth needs to be slow in healthy infants. Unfortunately, this is far from ideal for a ELBW who is desperately trying to grow as quickly as a fetus. A 24 week infant going from 500g at birth to 2500g at NICU discharge 3 months later is a 400% increase. If a term baby born weighing 3.5kg grew this quickly it would weigh the same as a 5 year old (17.5kg) by 3 months age. Low protein is a necessary component of optimal development.

In my next post, I’ll be discussing breast milk protein in different mammals, brain growth and how humans differ from most other mammals. Thanks for the read.

I’d be grateful for your help in sharing this, and the Baby Loss project posts, with others interested in NICU nutrition and/or Baby Loss. I’m not interested in getting likes or views on their own; I’m interested in connecting with others to see if we can improve outcomes, through collaboration, raising awareness, sharing innovations and good practice, and education. Thanks for any shares, re-stacks.

Also posted here on Substack.

I want to share content for all things NICU nutrition related especially with a view for global collaboration. I want YOU to help me make a difference to the sick newborns in LMICs.

I want to learn how best to translate knowledge to, and share good practice and evidence with less well resourced settings. I want to find out what works in your settings, and what ideas and solutions you have. Our practice in High-income country (HIC) settings is guided by systematic reviews, RCTs and years of experience, but translating that to resource limited settings is challenging. The risks and benefits of faster/slower feeding is context dependant and impacted by population differences (higher rates of IUGR), baseline infection rates and available resources (e.g. PICCs). Let’s be honest, we are all guided by Cochrane etc. but 90% of what we practice is experiential. Show me a single successful RCT powered on a primary of NEC and I’ll buy you lunch. An intervention that is beneficial in HICs (high quality probiotics) could be lethal in LMICs.

My clinical career (qual. MBBS 1990) has been in a well resourced setting - the UK, where we care for babies from 22 weeks and 400g with unrestricted access to PN, intravenous lipids, supplements, minerals and fortifiers, as well as biochemistry, dieticians and high nurse:patient ratios.

I’ve published hundreds of papers, many of which individually probably made little difference to clinical care, but cumulatively I hope added to our understanding of nutritional needs and practice.

I then imagined that in resource limited settings where I’ve been fortunate to visit, such as Kenya, Latin America, Philippines, most preterm babies <28 weeks or <750g wouldn’t survive. However, even in settings such as Kenya, where there were no ventilators or surfactant, no PN, no fortifiers, I saw babies born at 25-26 weeks weighing 600-800g surviving just on Mother’s Own Milk, MOM and good nursing care (warmth, infection control, Kangaroo and milk).

However, a lack of access to routine biochemistry (sodium), supplements (calcium but no phosphate) and fortifiers results in universal growth faltering. Whilst I strongly believe that slower growth on MOM is preferable to faster weight gain on formula, there will be a point at which slow growth is a marker of inadequate nutrients for optimal brain growth. Humans are naturally innovative, and there are many local approaches that have been developed, but most have not been rigorously tested. Studies have explored high volume feedings (200-240ml/kg/day), energy supplements such as olive oil, MCT etc. and in some settings where access to breastmilk fortifiers is expensive, formula milk powder is added although of course the final milk composition given is always sub-optimal. In other settings, in-hospital access to formula and fortifier is effectively prohibited because of rigid adherence to BFI. We can all see the benefits of BFI culture, but the adverse growth impact on individual VLBW feels wrong.

There may be many babies 1250-1500g who will do fine with high volume MOM, some extra sodium and lots of KMC, below that I’m not so sure.

Is it really possible for a <1000g baby to grow optimally just on breastmilk?

Also posted here on Substack.