Colostrum and Colostrum Harvesting

Colostrum is the first milk produced by mums. It is known as liquid gold due to the incredibly potent immune properties. In this post we look at the properties of colostrum in more detail and provide an overview of when and how to collect colostrum.

What is colostrum?

Colostrum is the first breast milk produced by mums. It is different to later breast milk in its composition, appearance and consistency. Breasts can begin producing colostrum as early as in the first gestation of pregnancy.

Colostrum has a higher protein content than mature breast milk and slightly lower concentrations of carbohydrates, fats and water. It tends to be thick and sticky and is usually a yellow or straw-like colour, although these properties can vary between women.

Colostrum is incredibly rich in immune boosting components, for many of these compounds they are significantly more concentrated in colostrum compared to later breast milk. These include:

• Antibodies
• Immune proteins
• Growth factors
• Hormones

Why harvest colostrum?

For the first few days post birth your breasts do not produce large volumes of milk. Trusting that the low volumes baby receives at this stage can be difficult, especially considering the alternative is often to offer baby much larger volumes of formula. However, as noted above, colostrum is a different substance to other milk and is perfectly adequate to meet young babies’ needs.

Having a surplus of colostrum during these days can provide a welcome comfort for when you need some extra support, especially if breastfeeding is challenging, or you / baby are experiencing pain or health concerns. It can also be given to further boost and support baby if they are unwell or if breastfeeding is impacted in later stages.

A recent systematic review found that harvesting colostrum antenatally was associated with greater breastfeeding durations for women with diabetes. They also noted qualitative themes suggesting colostrum collection can help women physically and psychologically prepare for breastfeeding.

Another intervention study found that most women encouraged to try colostrum harvesting in pregnancy benefitted by having increased confidence in and commitment to breastfeeding. Some studies have found positive associations between colostrum harvesting in pregnancy and breastfeeding outcomes, both anecdotally and statistically, while others have failed to report significant differences or clear correlations.

When to collect colostrum?

Despite colostrum being produced from quite early in pregnancy, it is not advisable to attempt to express and collect colostrum until you reach full term.

Most sources advise that it is safe to harvest colostrum from 37 weeks gestation onwards. Colostrum harvesting may not be safe for those at risk of pre-term labour, or those with complications such as low-lying placenta or pregnancy-related bleeding. Always discuss colostrum collection with your midwife or doctor first.

Colostrum harvesting requires stimulation of the breast and nipple before using expression techniques to initiate the let-down reflex (with hand or pump). This process triggers the release of hormones, including oxytocin, which are also involved in the opening of the cervix during labour. Colostrum harvesting too early can induce these responses and may lead to early labour, so timing is extremely important.

If deemed safe, after 37 weeks colostrum can be collected as often as desired before birth and for the few days after birth. Around 3–4 days after birth, changes within the breast lead to a shift in breast milk composition. Colostrum becomes transitional and later matures into breast milk.

How to collect colostrum?

As mentioned above, you can collect colostrum by using hand expression or breast pumping techniques.

It is often advised to use hand expression for colostrum harvesting, as it is released in very small amounts—using your hands and a small container such as a syringe or mini pot works best.

It can take time and/or repeated attempts to collect colostrum, especially when doing so for the first time. Be patient, remain relaxed, and seek support from your midwife or lactation consultant if needed.

Follow the steps below to have a go at colostrum harvesting yourself:

• Wash your hands before you begin and make sure you have a clean, sterile collection container. Syringes or small pots with lids work well.
• Ensure you are warm and comfortable, with enough space, time and privacy before beginning.
• It helps to warm and stimulate your breasts beforehand—some suggest taking a warm shower.
• If hand expressing, start by creating a C shape with your thumb and fingers.
• Beginning at the nipple, feel back until you notice firmer, more textured breast tissue.
• Place your hand (in the C shape) where the breast feels firm. Press your fingers and thumb into the breast (towards your chest), then squeeze gently for a couple of seconds. Release and repeat until drops form on the nipple.
• Repeat this process around the breast to stimulate the full circumference.
• You may only collect a couple of millilitres—this is completely normal.
• Label your container with the date and store in the fridge (up to 4 days) or freezer (up to 6 months).

References

Ablett, L. H., Hopper, H., & Maslin, S. (2023). How to promote exclusive breastfeeding with antenatal milk expression and implementation science: A mixed methods systematic review. Health Sciences Review, 9, 100124. https://doi.org/10.1016/j.hsr.2023.100124

Demirci, J. R., Glasser, M., Fichner, J., Caplan, E., & Himes, K. P. (2019). “It gave me so much confidence”: First-time U.S. mothers’ experiences with antenatal milk expression. Maternal & Child Nutrition, 15(4), e12824. https://doi.org/10.1111/mcn.12824