Sleep & the Breastfed Baby, Part 1
When I was a new mom, the most common question I was asked about my new baby was "How is he sleeping? Is he sleeping through the night?"
It always felt like there was a measuring stick being held up to him - and me - judging whether we were achieving parenthood's first big milestone of sleeping through the night. (Which by the way, is a very modern western ideal.) My baby was nursing every few hours and I didn't really mind…except I started to feel like there was something wrong, or at least I wished I could respond to the constant questioning with the answer people wanted to hear. With my subsequent three babies, I learned to side step the question by answering with, "She's sleeping like a baby!" This change of perspective brought a peaceful acceptance of night nursing that allowed me to enjoy those middle-of-the-night feedings... or at least to better cope with them knowing it was normal.
Not only is it normal for a breastfed baby to night nurse, but it is also beneficial.
This is almost completely lost on our society that is used to bottle feeding patterns. Studies show that babies who sleep long stretches at night are at increased risk of Sudden Infant Death Syndrome (SIDS). They are more likely to get into a prolonged deep sleep and less likely to rouse out of it if their oxygen drops. The frequent night wakings of a healthy baby help increase arousals which keep babies in safe sleep states and help them recognize their own hunger. In fact, most of the safe sleep guidelines are oriented around helping babies sleep lightly and avoid prolonged periods of deep sleep. Breastmilk actually feeds the development of the part of the brain responsible for helping a baby wake up when there is danger.
Another reason formula fed babies eat less often at night is because its possible for caregivers to push larger volumes of milk in the daytime without the limitations of breast storage capacity or milk supply. In contrast, breastfed babies usually self-limit their feed size to 3-4 oz and therefore need night feeds to get enough food. Studies have found over and over again that the small frequent feeds of a breastfed baby lead to better health outcomes and prevent obesity. Most mothers and babies need 7-10 breastfeedings per 24 hours to sustain a full milk supply and growth, even beyond the newborn period, because feeding patterns are restricted by mom's milk storage capacity (see infographic). If there are long stretches between nursing sessions, the accumulating milk in mother's breasts signals her body to decrease production as the body thinks the unused milk was wasted energy expenditure.
It varies for every mother/baby pair, but the first month postpartum 8 feedings per 24 hour day with one 5 hour stretch seems to be a common tipping point before the signals to decrease supply are triggered. Interestingly, 5 hours is also the medical definition of sleeping through the night. 5 hours will get you from about 9pm to 2am. Interestingly, there is a surge of prolactin that mothers experience around 2am that results in a surge of milk production. Because of this, breastfeeds that occur around 1-3am are usually the biggest feed of the whole day and therefore go a long way to support infant growth and sustain milk supply. However if the 5 hour stretch is regularly exceeded, most women will experience a gradual decline in milk supply and struggle to achieve their personal breastfeeding goals. It may not always be immediately apparent, but after weeks or months of baby "sleeping through the night," mother may start to notice her supply and baby's weight percentiles have dropped to a concerning level. In fact, the so-called 4 month "sleep regression" is often a result of low milk supply and a caloric deficit after a period of baby sleeping through the night.
When does the 5 hour guideline no longer apply?
We recommend mothers continue to get in at least one night feed between 1-3am until their baby is established on solid foods (often around 8 months). At that point, baby is eating three solid food meals a day and a gradual decline in milk supply becomes part of the normal weaning process. The notable exception before 9 months, is a mother with an unusually large breast storage capacity (see infographic) who may be able to maintain a full supply even with a baby sleeping long stretches. If you feel you have a high milk storage capacity, excellent milk supply, a choose to let your baby sleep through the night, its important to check their WHO weight percentiles monthly to ensure they are continuing to get enough milk in the daytime to meet all their needs. If baby starts to drop weight percentile more than 5% per month, this indicates they still need night feeds to sustain their growth.
Thankfully, there ARE solutions to help you maximize supply AND sleep: