Liggins Institute


DIAMOND stands for DIfferent Approaches to MOderate & late preterm Nutrition: Determinants of feed tolerance, body composition and development. It's a study that's looking at different ways of providing nutritional support to premature babies who are learning to feed.

Tube feeding a premature baby

What is the DIAMOND study?

The DIAMOND study is looking at different ways of providing nutritional support to preterm babies who are learning how to breastfeed. We’re trying to find out if the way nutrition is provided affects the way they grow, the amount of fat in their bodies, and their brain development. These are all things that can influence their chance of becoming obese later on in life.  

Two of the feeding methods we’re looking at are already used to provide nutrition to babies who are born early. The third method is a new idea to give babies a smell and taste of milk BEFORE they are fed through a tube into their stomach.

We’ll also investigate whether breast milk is different for girl babies than boy babies.

What type of babies are we interested in?

We’re interested in moderate-to-late preterm babies, which are babies who are born when mum is 32 – 36 weeks pregnant.

Why are we interested in moderate-to-late preterm babies?

We’re interested in these babies because babies who are born early have a hard time feeding. They don’t have the fat stores to keep them going until mum’s milk comes in. They also can’t co-ordinate the sucking, swallowing and breathing needed to breastfeed, which tends to delay mum’s milk even more. The earlier they are born, the less their tummies can cope with milk. On top of this, mums of preterm babies are often unwell which means it can take even longer to get a good milk supply.

Why is this study important?

We know breast milk is best for baby, but because babies who are born early have a hard time feeding, they need some help to make sure they get right nutrition until breastfeeding is underway. This study will investigate the different ways of giving this nutrition to preterm babies to find out how it affects their fat stores and brain development. If we can improve the way we feed preterm babies and stop them losing too much weight, it might stop them developing extra fat mass that can lead to obesity later on in life.

At the moment we don’t know very much about how the nutritional support we provide to preterm babies affects their growth and development. That’s why the DIAMOND study is so important. It’s the first of its kind and will be the biggest study of preterm babies in the world.

Woman and baby

How do preterm babies currently receive nutrition while they're learning to breastfeed?

There are currently three ways of providing nutrition to moderate-to-late preterm babies while they learn how to breastfeed:

•    a sugar solution that’s put into a vein
•    a sugar and protein solution that’s put into a vein
•    infant formula that’s put into the stomach through a small tube

At the moment, any or all of these methods can be used to provide nutritional support to a moderate- to-late preterm baby, but we don’t know which one is best.

Why provide taste and smell?

Babies who are fed milk through a tube into their tummies don’t get to smell or taste the milk first. A small study has already found babies who had a smell and taste of milk before a tube feed started breastfeeding faster, and left hospital faster. As adults, we know that smell and taste is an important part of every meal, not just for enjoyment but to prepare the body to digest it properly. We want to know if smelling and tasting milk first will help tube-fed babies tolerate feds better and reach full feeds more quickly.

Why are we interested in the difference between breast milk for boys and girls?

Currently preterm boy babies and girl babies are fed the same until breastfeeding is underway. But boys and girls process food differently and grow differently. That’s why we want to find out if breast milk is different for boys and girls, so that we know whether we should feed preterm boys and girls differently.

Why are looking at babies’ stool samples and what is the microbiome?

As part of the study we will collect stool (poo) samples from babies to look the microbiome. The microbiome is the bacteria in our gut that contains genetic information about us. It can affect our chance of getting diseases like obesity, diabetes, asthma and many more. Studying baby’s microbiome could help us work out the best feeding method for our microbiome now and in the future.

What happens to babies who take part in the study?

Mums who enrol in the study must plan to fully breastfeed. Your baby will be randomly assigned to one of the three methods of nutritional support that we described above while they learn how to breastfeed. The goal for all babies who take part is to receive all breast milk feeds as soon as possible.


PEAPOD machine

How will we measure the fat mass of the babies?

The babies will have their fat mass and fat free mass measured using a machine called a PEAPOD. It’s a very safe process and doesn’t hurt your baby in any way. Your baby is weighed first and then lies in the PEAPOD for two minutes while the measurement is made.

Other optional parts of the study:

To find out whether smelling and tasting milk before a tube feed improves digestion, we’ll use an ultrasound to see how quickly the milk leaves  baby’s stomach. To see the effect on blood flow and oxygen in the brain, we’ll use a special light attached very gently to baby’s forehead.  

The ultrasound is similar to the scans you had when you were pregnant and isn’t painful and doesn’t hurt your baby in any way. The blood flow assessment is like the oxygen probe your baby will have on their hand or foot when they’re in hospital, except it’s placed on the forehead. Again, this doesn’t hurt them in any way.

When and how will we test the babies’ development?

If you take part in the study, we’ll ask you to come back when your baby is four months old and then at two years old (corrected age) for some standard tests to check their development.

How do I find out more?

To ask a question or find out a bit more about the study, just fill out our enquiry form and one of the team will get back to you.