Why newborn babies lose weight - and why 10% matters
It is routine for newborn babies to be weighed soon after birth. This is not just to inform the happy family and friends but o give a baseline for ongoing recording. Weighing and measuring should wait until the baby has had uninterrupted skin to skin contact and the first breastfeed in the hours after the birth.
All full-term babies are born over-hydrated. Floating around in amniotic fluid in the womb, which they sip and swallow as well as absorb through the skin, this extra hydration supports the concentrated colostrum which is the first milk babies receive from the breast. As they process and excrete this extra fluid, babies lose weight in the first week of life which is typical and expected. Up to 7% of birth weight is considered normal but many babies lose as much as 10% - the point where medical staff will usually recommend the following protocol:
Breastfeeding at least 8 times in 24 hours
Hand expressing and/or pumping after each breastfeed
Supplementing breastfeeds with expressed breastmilk and/or infant formula.
This is a short-term approach which supports the baby while the breasts continue to establish production. It is sometimes referred to as Triple Feeding.
Some things you need to know
Parents often feel great alarm at the news their baby has lost more weight than ideal. It is important to know this can happen for several reasons. These include:
Babies who are born by caesarean
Babies whose mothers were given IV fluids (a drip) during labour and delivery
Babies born to older mothers (35 plus)
Babies who are their mother’s first baby
These factors are associated with delayed onset of lactation and should be considered when assessing babies weight loss.
The most important things to do when a baby has lost 10% or more of their birth weight are:
Feed the baby and Protect the milk production
Milk production in the early weeks relies on feedback from the baby removing milk effectively and frequently. Until the baby can be relied on to do so, their mother needs to step in with her hands and her pump to keep production on track.
How parents are told about their baby’s weight is incredibly important. Too often, mothers are frightened by the language used and breastfeeding is abandoned altogether due to fear for their child’s health and safety. You can see why:
“Your baby is starving”
“Your baby is failing to thrive”
“You aren’t making enough milk for your baby”
“Your baby is at risk of dehydration [and other medical outcomes]”
Excessive weight loss in newborns, left untreated, can lead to serious complications. However, in the case of a baby who has been monitored since birth and has been identified of being at risk is very different to a baby who is not under medical supervision. Actual risk is very low.
If your lactation onset is delayed, as happens for some women, then mother and baby will need a few days of additional support until breastfeeding can progress in the usual way. Stanford Medicine have a suggested script for medical staff, which is much less alarming for parents:
Some babies jump the gun and temporarily need a bit more fluid until your milk comes in. The best way to make sure everything eventually goes well is have three messengers (your baby, your hands and your pump) send signals to your breast to bring in your milk. At the same time, we will give your baby the advantage of a little extra fluid and calories, so she/he will be vigorous at the breast.
Once your production is up, we won’t need to supplement.
This last point is incredibly important. Too often, mothers are still anxious about their supply weeks or months later and continuing triple feeding long past the point of concern.
