Baby development week by week: the complete first-three-months guide

Why only the first three months — and why week by week

The first three months after birth are called the fourth trimester — the baby is adjusting from the womb's world to this one, and the changes outrun a monthly count. What is normal in week one (weight loss) is a checked-out concern by week four — hence weeks.

Past three months the pace settles into a monthly stride — the month-by-month development pages guide the road from there. This series exists for the tunnel that feels longest and passes fastest.

Every week keeps one structure: what changed in the baby; how the mother is (she is a character in this story, not its patient); the week's tasks; an at-a-glance table; and each page's most valuable list — when to see a doctor at once.

The twelve weeks, mapped

The rough map is below — with two warnings: every baby keeps its own clock, and the bands are weeks wide. A map's job is showing the road, not holding examinations.

The rules that hold for all three months

Breast milk only until six months — no water, ghutti, honey, animal milk or dal water. Sleep always on the back, on the baby's own flat surface, in your room — no pillow, no heavy quilt.

Fever in a baby under three months is an emergency — hospital immediately, and no self-dosing. That sentence appears on every page of this series, because it is the sentence that does the most work.

ASHA's home visits (days 3, 7, 14, 21, 28, 42), the MCP card's weighings and the UIP's free vaccines — that government trio is the first quarter's backbone. And shaking, never — when the crying cannot be settled, putting the baby down safely and stepping away is the right road.

Screens are zero at this age — the baby's screen is your face. And above every piece of advice — this series included — sits one court: your paediatrician. These pages describe the common road; your baby's road is theirs to set.

The see-a-doctor-at-once list, any week

Fever or a very cold body; refusing feeds; fast breathing (over 60/minute) or ribs pulling in; lethargy that doesn't rouse; fits; spreading jaundice; falling wet nappies; blood in the stool; a continuous thin, weak cry.

Any of these — no home remedy, no waiting, no 'we'll see in the morning'. The nearest hospital, and 108 in an emergency. This list is not for fear; it is for memorising — households that know it by heart arrive on time.

This series is general information only — no substitute for personal medical advice. The people who can weigh your baby's full picture are its own doctors.

Frequently asked questions

Q: How do I know if the baby is 'behind'? — Every milestone's band is weeks wide — compare with this baby's own last month, not the neighbours. Each page carries its red-flag list separately; anything on it goes to the doctor that week, everything else gets patience.

Q: How do these weeks apply to a premature baby? — By corrected age — subtract the weeks of prematurity when reading. Vaccine dates run on the real birth date; developmental milestones on the corrected age. Have the doctor set both clocks once.

Q: The family traditions — massage, the black dot, the forty days — keep or drop? — Keep most of them: massage, morning sun, the forty days' rest, the crowded warmth of family — all on the baby's side. The hard lines are few: nothing in the mouth but milk, no kajal in the eyes, nothing inserted in the navel, nose or ears, and sleep on the back.

Q: What comes after three months? — The month-by-month development pages — the whole road from rolling to first steps. And at the six-month door, the first food — its preparation lesson lives there too.