Colostrum harvesting - Expressing your milk in the antenatal period

Colostrum Harvesting/Expressing Your Milk in the Antenatal Period

Patient Information Leaflet

Maternity

• Author ID: KA 
• Leaflet ref: Obs 050
• Version: 7
• Leaflet title: Colostrum harvesting/expressing your milk in the antenatal period.
• Last review: January 2026
• Expiry date: January 2028

Expressing your milk during the antenatal period

Wrightington Wigan and Leigh NHS Foundation Trust is committed to promoting and supporting breastfeeding as the healthiest way to feed your baby. We believe that breastfeeding should be recognised as a unique interaction between mother and baby which not only feeds and comforts but also helps prevent against infection and disease.

It is well known that exclusive breastfeeding (that means your baby has your milk and nothing else to eat or drink) for around the first 6 months, has many health benefits.

Importantly, in accordance with the Trust Infant Feeding Policy, and UNICEF Baby Friendly UK Standards, pregnant women should not be asked about their planned mode of feeding; instead, they should be given information about the value of breastfeeding (especially if  the mother is diabetic), and also about the value of antenatal expression of colostrum (first milk), if appropriate; they should be encouraged to decide how they wish to feed only once they meet their baby.

Why should I express my milk antenatally (before baby’s birth)?

Any expectant mother can express her breast milk from 37 weeks gestation. It is particularly useful if you know that your baby is at an increased risk of having a low blood sugar in the first few hours after birth. This can include:

• Women with diabetes in pregnancy (pre-existing or gestational).
• Infants diagnosed during the antenatal period with cleft lip and/or palate and congenital conditions.
• Mothers having an elective caesarean section.
• Infants with intrauterine growth restriction.
• Women with breast hypoplasia (underdeveloped breasts).
• Women with hyper androgenesis (polycystic ovarian disease).
• Women who have had breast surgery.
• Women with multiple sclerosis.
• Strong family history of dairy intolerance or inflammatory bowel disease.
• Mothers with high blood pressure.
• Mothers taking beta blockers (e.g. Labetalol).
• Previous unsatisfactory breastfeeding journey.

It would be helpful if you have already expressed some of your breast milk, so that if your baby does need extra milk, this can be given to them instead of formula milk. The ideal time to do this is before your baby is born. 

Diabetes and allergic conditions

Mothers with a family history of dairy intolerance, inflammatory bowel disease or diabetes are more likely to have babies who develop these conditions if they are exposed to cows’ milk early in infancy.

• Babies who are breastfed are less likely to develop childhood diabetes.
• It is thought that cows’ milk (the main ingredient of formula milk) can trigger diabetes in some babies; this is probably more likely if you or your partner have diabetes. Therefore, it is very important for mothers who are diabetic to avoid giving their baby formula milk - if possible until the baby is at least 6 months old.
• If you have diabetes and are insulin dependent, you may find that you need less insulin when you are breastfeeding, and that you need to eat more.
• If you have gestational diabetes, you are less likely to go on to develop diabetes in later life if you breastfeed your baby.

Induction of labour 

Women undergoing induction of labour should be encouraged to start antenatal expressing and storage of colostrum during the induction process, or to continue to do so if they have already started before admission to hospital. Ward staff should provide guidance on the technique, and also syringes, which would be used to store any colostrum obtained; staff should provide these to all women admitted for induction of labour, along with information about why women should express their milk antenatally.  It should be noted that nipple stimulation may assist with cervical ripening, but there is no significant relationship between nipple stimulation and inducing labour. 

Contraindications

There is no evidence that daily hand expression of colostrum can trigger labour for women who are not known to be at risk of premature labour.

The antenatal expressing of colostrum is not meant to be done in the following circumstances:

• History of threatened/ actual premature labour.
• Cervical incompetence
• Multiple pregnancy
• If there is a cervical suture in-situ (in place)

If you experience any uterine contractions during expressing, you should stop. If these continue, please contact your midwives. 

Concerns regarding safety 

Antenatal expression of colostrum has long been a widely recommended practice for the reasons stated. Concerns in the past regarding the risk of premature labour due to stimulation caused by the release of the hormone oxytocin during antenatal expressing, are not supported by the evidence and are theoretical (meaning they have not happened in real life situations). It should be remembered that it is normal for women to continue to breastfeed older infants and/or children throughout future pregnancies with no higher reported rate of early labour. When it is likely that the pregnancy will go to full term, it is appropriate to encourage hand expressing from 36 weeks gestation, but as previously stated, there is no evidence to support concerns about antenatal expressing, and women should therefore be encouraged to do so if possible.

How to express your breast milk

Hand expressing milk simply means squeezing milk out of your breast, and this is how you do it: 

1. Cup your breast with your hand and feel back from the end of the nipple to where the texture of your breast feels different. 
2. Using your thumb and index (first) finger, gently squeeze this area. It should not hurt.
3. Release the pressure then repeat again and again, building up a rhythm. Avoid sliding your fingers over the skin.
4. Milk should start to flow. The first milk, colostrum, is very concentrated. It is very thick and will come out of your breast drop by drop. 
5. If the milk does not flow, try moving your fingers slightly toward the nipple or slightly further back, so as to find the spot that works best for you.
6. When the flow slows down, move your fingers around the breast (like moving around the numbers on a clock face), so that you have expressed the milk from all the way around your breast.
7. Express from the other breast. 
8. If you wish to see hand expressing online, please visit: www.unicef.org.uk/BabyFriendly/Resources/AudioVideo/Hand-expression/

How often can I express?

You can express your milk as often as you want to, but we would recommend at least four times a day.

How much breast milk will I get?

The amount of breast milk you get will vary from a few drops to a teaspoon. This small amount is perfect for your baby, as colostrum is very concentrated in nutrients, and it helps your baby fight infections.

You may find when you express, that you feel your womb going hard and then relaxing; these feelings are known as ‘Braxton-hicks’ contractions. Do not worry about these unless they begin to feel like period-type cramps or mild labour contractions. This is rare, but if it happens, you should stop expressing and rest. 

If they do not stop and you think you may be in early labour, you should telephone the Delivery Suite on the number on the front of your notes as advised by your midwife (01942 778505). 

How to store your expressed milk

It is best to freeze your colostrum when you collect it at home and then bring it into hospital at the time it is needed. You will need to collect the milk in clean containers. Your Community Midwifery team will provide you with small syringes that you can use to store the milk in. The syringe can then be put into a small plastic bag and labelled with your details - name, date, and time you expressed. 

You will also be given a log sheet to record the number of syringes you have in the fridge/freezer whilst in hospital.

Syringes and packs can also be collected from Infant Feeding Team - 01942 778557, or Antenatal Clinics.

You can store the milk in the fridge at a temperature of 2-4 degrees centigrade for 3-5 days, or in the freezer for up to 6 months. If you do not know the temperature of your fridge at home, store for 48 hours only.

If you start expressing at 37 weeks, it will probably be best to store the milk in the freezer.

When you come to have your baby

Do not forget to bring any breast milk you have expressed with you. Let your midwife know you have it with you as soon as you arrive, and she will arrange for it to be stored in the fridge or freezer if already frozen. If your breast milk is frozen, then the best way to transport it to the hospital is in a Cool bag with a blue ice block. Frozen breast milk needs to remain frozen until needed, so please give it to your midwife on admission to hospital. 

• A member of staff will check your syringes into the fridge/freezer, with you making a note in your log sheet.
• If you need a syringe to give to your baby, then a member of staff will collect the syringe from the fridge/freezer, and sign this out of the fridge with you by confirming that your name and hospital number match the labelled syringe.
• This is to ensure that your milk is stored correctly and that you can be confident that your milk is being given to your baby.
• If you go home and leave EBM (expressed baby milk) in the freezer, this will be discarded, as we have limited storage capacity.

Contacts/Further information

If you require further information regarding the evidence printed in this leaflet, please contact the Infant Feeding Team on 01942 778569 or 01942 778557 or refer to:

www.nice.org.uk 

https://www.unicef.org.uk/babyfriendly/