Stage 1 · Birth
Birth
What shapes your baby’s birth weight, and how to feed them in the first days.
Babies born at full term, between 39 and 41 weeks, tend to have fewer health problems than those born early or late, and labour is often more straightforward.
One of the first things your care team will check is your baby’s weight. It’s a simple measure that helps them understand how your baby grew and what support they may need.
What affects birth weight?
Every baby is different, and many factors play a part.
Parents' build
Both parents' height and weight.
Mother's age
Babies of teenage mothers and mothers over 35 may be smaller.
Birth order
First babies are often lighter than siblings born later.
Twins and multiples
Usually smaller than single babies.
Early arrival
Babies born before 37 weeks tend to weigh less.
Mother's weight
Higher weight in pregnancy can mean a larger baby.
Lifestyle
Poor diet, smoking and alcohol can lower birth weight.
Baby's sex
Boys are usually slightly heavier than girls.
Health in pregnancy
Anaemia, high blood pressure or diabetes can affect weight.
Your midwife or doctor will track your baby’s growth and tell you if anything needs attention.
Feeding your newborn
Every family’s feeding journey is different. Here’s what to know.
Nutrition in the first days
Your newborn’s stomach is tiny, about the size of a cherry on day one, so frequent small feeds are normal. Most newborns feed 8–12 times in 24 hours.
- Watch for early hunger cues like rooting, sucking on hands or lip-smacking, rather than waiting for crying.
Breastfeeding
Breast milk is the best source of nutrition for your baby. The WHO recommends starting within the first hour after birth and breastfeeding exclusively for the first six months.
The first milk, colostrum, is thick and yellowish and rich in antibodies that help protect your baby. Skin-to-skin contact straight after birth helps your baby latch and supports your milk supply.
- If feeding is painful or your baby struggles to latch, ask your midwife or a lactation consultant early.
Formula feeding
If you can’t or choose not to breastfeed, infant formula gives your baby the nutrients they need. Always follow the instructions on the pack.
Hold your baby semi-upright, pace the feed, and let them decide when they’ve had enough.
- Use water boiled and cooled to no less than 70°C, measure powder exactly, and make each feed fresh.
Combination feeding
Many families combine breast milk and formula. If you’d like to keep breastfeeding, try to establish it first over the first few weeks before introducing bottles, as this helps protect your supply.
- Your health visitor or midwife can help you find a routine that works for your family.
This information is for general guidance only and doesn’t replace advice from your doctor, midwife or health visitor.
