Harvesting Colostrum Before Birth

What antenatal expressing is

Colostrum is the concentrated first milk your breasts make, and they start making it well before birth. Antenatal colostrum harvesting — sometimes called colostrum harvesting or antenatal expression — means hand expressing small quantities in the last weeks of pregnancy, drawing them into a syringe, and freezing them so there is a supply ready if your baby needs it in the first hours.

It is not preparation in the sense of toughening nipples or testing whether you can breastfeed. It is a practical insurance policy for babies at higher risk of low blood sugar or early feeding difficulty, and it is offered for that reason.

Who it is usually offered to

The Association of Breastfeeding Mothers describes antenatal expressing as recommended where there is a raised chance of feeding difficulty or blood sugar problems — for example where the mother has diabetes, where the baby has a cleft palate or a congenital condition, where growth has been restricted, or with multiples. It also mentions a family history of cow's milk protein sensitivity or type 1 diabetes.

North Tees and Hartlepool NHS Foundation Trust's leaflet lists a similar set, including babies expected to be large or small for gestational age, cleft lip or palate, Down's syndrome, and maternal diabetes, pre-eclampsia or high BMI — while adding that "any woman can decide to harvest colostrum for use in the early days."

The clearest evidence sits with diabetes. The DAME trial, published in The Lancet in 2017, randomised 635 women with diabetes in a singleton pregnancy either to express from 36 weeks or to standard care. Babies of the women who expressed were more likely to be exclusively fed breast milk during their hospital stay, and the trial found no evidence of harm in that low-risk group. NICE's guideline on diabetes in pregnancy is the reference point for how diabetic pregnancies are managed around birth.

When to start

The usual figure is 36 weeks. The ABM says "mothers are normally advised to wait until around 36 weeks before starting antenatal expression." North Tees puts it as "you can start collecting colostrum from 36 weeks pregnant but it is never too late to start."

The reason for the wait is oxytocin. Nipple stimulation releases it, and while the amounts involved are small, the caution exists because nobody wants to bring on labour early.

Who should not do it

This is the part most commercial guides skim. The ABM notes it "may not be recommended if you've been at risk of preterm labour in previous pregnancies, or have a surgical stitch, for example." The same caution generally applies if you are having contractions, if you have been told your cervix is short, if you have had bleeding in this pregnancy, or if you have been advised to avoid anything that could stimulate the uterus.

Ask your own midwife or obstetrician before you start, particularly with a multiple pregnancy or any history of preterm birth. This is a case where the general leaflet cannot answer the question.

How to do it

Use your hands only. Do not use a pump before birth — the suction is stronger than needed, the volumes are far too small to reach the collection bottle, and pumps are not what any of the antenatal guidance describes.

Build up gradually. North Tees suggests you "can start hand expressing for a few minutes once a day when you are 36–37 weeks pregnant" and then "gradually build up to gently expressing for about 5–10 minutes at a time, 2–5 times a day." The ABM's version is similar: "try hand expressing for a few minutes, 2 or 3 times a day."

The technique is ordinary hand expression: thumb and finger pads well back from the nipple, press towards the chest wall, compress, release, repeat in a rhythm, and rotate around the breast. A warm bath or shower beforehand helps. Collect straight into a small sterile syringe, or into a sterile spoon and then draw it up.

Storing and labelling

Label every syringe with your name, the date and the time. North Tees's leaflet asks for exactly that, and it matters because the hospital needs to know how old the colostrum is.

Colostrum can be topped up into the same syringe over the course of a day if it is refrigerated between uses — the ABM notes it "can be collected two to three times each day in the same syringe" — and then frozen. The ABM states that frozen colostrum "can be stored for up to six months in the freezer" and that "once thawed, it should be used within 24 hours." North Tees gives storage temperatures of -18°C in the freezer, or 2–4°C in the fridge for up to 24 hours before freezing.

Bring it in frozen. North Tees advises asking someone to bring a few labelled frozen syringes in a re-sealable food bag, transported inside a cool bag between two blue ice blocks. Leave the rest at home in the freezer until you know you need it.

When to stop and reassess

North Tees gives an unambiguous instruction: "If you begin to feel 'period-like' cramps or mild labour contractions, stop expressing, rest and then start again slowly." If cramping keeps happening, stop and speak to your midwife rather than pushing through.

Getting nothing is also common and is not a prediction. Some people collect several millilitres a day, some collect a few drops, and some collect none at all — and none of that forecasts how breastfeeding will go. Colostrum production after birth is driven by the hormonal shift of the placenta being delivered, which has not happened yet.

When to ask

Speak to your midwife or obstetrician before starting if:

• You are expecting twins or more, or have had a preterm birth before.
• You have a cervical stitch, a short cervix, or have had bleeding in this pregnancy.
• You have been advised to avoid anything that could stimulate contractions.
• You are under 36 weeks and have been told to start earlier — ask why, and get it in writing on your notes.

Where to get real help

In the UK the National Breastfeeding Helpline is 0300 100 0212, run by the Breastfeeding Network and the Association of Breastfeeding Mothers, and open every day of the year. La Leche League GB runs local groups and a helpline. In Ireland the HSE offers an "Ask our breastfeeding expert" live chat and email service, Monday to Friday. Your maternity unit may also run an antenatal expressing workshop — ask at a routine appointment.