The first days of feeding a newborn are often the most uncertain and anxiety-provoking of early breastfeeding — particularly for first-time parents who cannot see how much milk the baby is taking and are simultaneously managing the aftermath of birth, sleep deprivation, and the overwhelming experience of a new baby. Understanding what is actually happening in the first days of breastfeeding, what is expected, and how to know the baby is getting enough provides a foundation for the early weeks.
Healthbooq supports breastfeeding families through the early weeks of establishing feeding with evidence-based guidance on what to expect, how to know things are going well, and when to seek support.
What Colostrum Is
The first milk produced by the breasts is colostrum — a thick, concentrated fluid that has been present since approximately thirty-two weeks of pregnancy. It is produced in small volumes: typically two to twenty millilitres per feed in the first one to two days. This small volume is appropriate for the size of the newborn stomach (approximately five to seven millilitres on day one — the size of a marble) and is rich in antibodies, immune factors, and growth factors that the newborn requires in the early days.
The concentration of colostrum means that, despite the small volume, it meets the newborn's nutritional needs in the first days before mature milk comes in. Parents who are concerned that the baby is "not getting enough" because feeds are very short or because they cannot feel breast fullness are often reassured by understanding this: the baby needs very little volume, and colostrum is very dense.
Milk Coming In
Around day two to four (or day three to five in first-time mothers), breast milk "comes in" — the transition from colostrum to transitional milk, which increases sharply in volume and changes in composition. This transition is driven by the drop in progesterone following the delivery of the placenta and is a hormonal process that occurs regardless of whether the baby has been feeding frequently (though frequent feeding from birth accelerates and supports it).
The feeling of milk coming in is unmistakable for most women — the breasts become noticeably fuller, sometimes very full and uncomfortable. Engorgement (excessive fullness) in the first days after milk comes in can make attachment difficult, and feeding the baby frequently is the most effective way to manage it.
Feeding Frequency in the First Days
Newborns need to feed frequently — at least eight to twelve times per twenty-four hours in the first days, and often more. This frequency is driven by the newborn's small stomach capacity, the rapid gastric emptying of breast milk, and the caloric needs of rapid growth. It is also the signal the breast needs to establish and maintain supply: frequent feeding stimulates the prolactin surge that drives milk production.
Newborns should not be left to sleep for longer than four hours between feeds in the first days without being woken. A baby who is very sleepy and difficult to wake for feeds in the first forty-eight to seventy-two hours should be assessed by a midwife, as this can occasionally indicate illness or jaundice.
Knowing the Baby Is Getting Enough
Breast milk cannot be directly measured, which is the primary source of parental anxiety about supply. The indicators that a breastfed newborn is feeding adequately are: nappy output (at least one wet nappy on day one, two on day two, and increasing to at least six wet and two dirty nappies per twenty-four hours from around day four); weight (an initial weight loss of up to ten per cent of birth weight in the first few days is normal; birth weight should be regained by approximately day fourteen); and behaviour (a baby who feeds, is alert between feeds, and then sleeps is feeding well; a baby who is continuously frantic or continuously impossible to wake is not).
Any concern about newborn feeding in the first days should be discussed with the community midwife or the hospital feeding support team before discharge.
Key Takeaways
The first days of breastfeeding involve a transition from colostrum (the early, concentrated milk produced from about thirty-two weeks of pregnancy) to transitional and then mature milk, which comes in at around day two to four. The volume of colostrum is small — a few millilitres per feed — but this is appropriate for the size of the newborn stomach on day one and two. Frequent feeding (at least eight to twelve times per twenty-four hours in the first days) is both what the newborn needs for adequate nutrition and what establishes milk supply. The signs that a newborn is feeding adequately are wet and dirty nappies and weight that returns to birth weight by about two weeks.
