Ask the IBCLC: How does milk supply fluctuate throughout baby’s first year?

It’s normal to see changes month to month or even day to day: Here’s what they might mean

Changes in your milk supply are completely normal—your breast milk will have variations even between the start and the end of a single feeding session. Most fluctuations are expected, though sometimes they can indicate an issue you need to address. Either way, there’s a reason for each change you might observe in your output, and the better you understand what they mean, the more control you’ll have over your breastfeeding journey. For this month’s Ask the IBCLC, our resident IBCLC Katie McGee answers questions about what changes to expect in your milk supply in the course of your baby’s first year, and what they might be telling you.

Does a mother’s milk supply vary from day to day, week to week, month to month?

Yes. You may notice that your milk appears watery sometimes and creamy other times. Your breast fullness of the early postpartum period may subside. These are normal milk changes throughout lactation.

Amazingly, milk composition changes even within a single breastfeeding session. The milk that comes out at the beginning varies greatly from the milk that is transferred to the baby at the end of a nursing session. Thirst-quenching and often fast-flowing with the letdown reflex, the “foremilk” released early in breastfeeding gets milk to the quickly-sucking hungry baby. “Hindmilk” transferred at the end of a breastfeeding session is like a heavy cream. This high-fat and high-calorie milk brings the baby to a satisfied and asleep state (not to mention he is so comfortable next to you – the very best place in his world). Variations in composition combine into the perfect balance for your baby.

Another variation comes in milk volume. The first milk you produce after delivery is low in volume but high in protective proteins for the baby during the newborn/colostrum phase. Although this is often a cause of concern for mothers, the colostrum phase is normal. It takes time, often several days, for a new mother to make a larger volume of milk. Frequently nursing your newborn – watching for any signs of newborn feeding cues – assists a new mother to transition from the colostrum phase to making larger amounts of milk. This is the transition commonly known as the milk “coming in.”

If a mother has identifiable risk factors for low production, an IBCLC may suggest a proactive plan, including pumping with a hospital grade pump, to assist with the establishment of a full supply to try to prevent problems. A call or visit with an IBCLC can help identify these risk factors and develop an action plan toward your personal goals.

Are there factors that can reduce or increase milk supply?

Yes! Sometimes mothers add pumping in addition to frequent breastfeeding and unintentionally boost supply or establish a supply that is above and beyond what the baby can take in. Oversupply can be challenging to manage. More commonly, low supply is the concern.

There are so many factors that can influence milk volume. Hormonal and anatomical variations with the mother, a mother’s medical, pregnancy and delivery history can impact both how quickly her larger milk volume comes in, as well as her ability to establish a full milk supply. Similarly, issues with the baby’s oral anatomy, and/or ability to breastfeed frequently and effectively, influence establishment and maintenance of milk supply. Any period of separation, particularly during the critical first two weeks after delivery, is a risk to the establishment of milk supply.

Some of these factors, such as C-section delivery or a NICU stay, may be unavoidable. Countering the influence with a pumping plan until you and your baby are together and nursing can bridge the gap until you and your baby are together again.

Is it normal to have fluctuations in supply?

Yes. After weeks of feeling breast fullness, it is not uncommon for a first-time mother to be alarmed when her breasts begin to have periods of softness. Typically, there is a leveling out of the milk supply to meet the needs of the infant at around 4-6 weeks.

Sometimes women have a milk supply that is very susceptible to variations in her breastfeeding and/or pumping routine. If a mother goes to an all-day wedding without the baby or a pump, or suddenly the baby is sleeping throughout the night, the next day or two can bring a dip in her previously stable milk supply. Other mothers may experience these schedule changes without any noticeable change in supply. If a mother previously had a full supply before this decrease, it can often be recovered with additional pumping and or nursing.

At what point should a mom be concerned about her milk production variations?

Trust your good instincts. If something does not seem right, pursue an answer from an expert. Watching diaper output, obtaining a weight check at the pediatrician’s office or visiting an IBCLC for a pre- and post-feeding weight can often provide assurances about newborn intake. Join a group online or in-person for nursing or pumping mothers (such as La Leche League). Mother-to-mother support is invaluable during lactation.

Is there a “normal” trajectory of milk output over the course of baby’s first year, and how big a deal is it if my supply differs from that trajectory?

In the early weeks, infant weight is a big focus. Babies are born with a reserve and are expected to have a decrease in birthweight before regaining to meet birthweight by two weeks old. During that time of lactation establishment, a new mother may make drops or milliliters of colostrum on day one. Colostrum is available in the perfect amount for the newborn who needs to adjust to life outside the womb much more than take in large amounts of food.

As the days and weeks go on, we look for a mother’s supply to increase to producing close to a liter of milk around the time her baby is two weeks old. There is much more opportunity to impact milk supply when we can intervene early to avoid problems. Get assistance early and often to help the first two weeks go well. This time period sets the tone for your milk-making throughout lactation.