Prolactin and Breastfeeding - The Science Behind Breastmilk

Prolactin and Breastfeeding - The Science Behind Breastmilk

If you’re breastfeeding you might have heard the term prolactin. Prolactin is the hormone responsible for breastmilk production. There are times throughout the day when levels of prolactin are naturally at their highest – and this means more milk output! Here’s what you need to know about prolactin and breastfeeding.

What is the relationship between prolactin and breastfeeding?

Prolactin is a hormone your body produces to tell your body it’s time to make milk. Before you got pregnant, your body produced prolactin but at a very low level. During pregnancy, levels of prolactin increased, and when you were at full-term they were at their highest. When you gave birth, these excess levels of prolactin are what made your body start producing milk for baby. Levels of prolactin remain quite high for the first 6 months postpartum while you’re breastfeeding – unless you’ve gotten your first period after baby, which can decrease levels of prolactin (this is why some women experience a temporary dip in milk supply during their period). Your body will continue producing prolactin at higher levels until you wean.

When are levels of prolactin at their highest?

Do you normally wake up in the morning feeling full? Do you notice you tend to leak during the night? Studies have shown that higher levels of prolactin are secreted at night, during your body’s normal sleeping time. This usually means that you’ll produce more milk late at night and early morning. This is why you may often wake up feeling full while you’re breastfeeding – and also why you may feel less full in the evening, when prolactin levels are at their lowest, and why breastfeeding and / or pumping at night is so important to build and maintain milk supply. In the first few months after giving birth, prolactin levels are at their highest. You should empty your breasts at least once through the night to avoid discomfort, engorgement or plugged ducts. After a few months, your milk supply will regulate and levels of prolactin will decrease and become stable. Once your supply regulates, you should notice less leakage during the night and feel less full in the morning. Your body will still follow the natural pattern of producing the most prolactin during the night, so if you’re looking to pump more milk you should aim to use your breast pump between midnight and 6am.

Each time you breastfeed or express milk, you’re signalling your body to produce more prolactin. This is the science behind milk production: more demand means more supply.

How to raise prolactin levels to make more breastmilk

Levels of prolactin secretion increase each time you breastfeed. This means that to raise prolactin levels, you should nurse or use your breast pump more often! Breastmilk production is based on supply and demand, so the more you breastfeed the more milk you will produce. When your baby is cluster feeding during a growth spurt, she is signalling your body to produce more prolactin – and more breastmilk.

Pumping methods to increase prolactin

There are a few different ways you can use your breast pump to increase prolactin levels. You can try power pumping, which is when you pump in short bursts several times over the course of an hour or more. Or, you can try cluster pumping, which is grouping several pumping sessions together during a 2-3 hour block. You can also try pumping while your baby breastfeeds, pumping between feeding sessions, and other breast pump techniques to maximize milk output. The more milk you express, the more prolactin your body will produce. 

If we missed out on anything you were wondering about in this post, please let us know! We'll be happy to update the post. Nothing more powerful than an informed mama :)