Baby's First Month: Week by Week Guide
What to expect in weeks 1, 2, 3, and 4 — physically, emotionally, and with sleep.
The first month is the most intense and the shortest. It's when the world is newest for the baby and most exhausting for the parents. The good news: there's a pattern. Knowing what comes week by week doesn't make it easier, but it does make it less terrifying.
Week by week
Week 1
Pure survival mode. Baby sleeps 16-18h but in 1-3 hour fragments. Breastfeeding hurts or is difficult — normal. The fontanelle may look bulging. The umbilical cord falls off between days 7-14.
Week 2
Baby regains birth weight (if not, talk to your pediatrician). Starts to focus on faces at 20-30 cm. Colic may begin — inconsolable crying in the afternoon/evening.
Week 3
Colic peak for many babies. Also parental exhaustion peak. Baby may have more alert periods — look at them when they're awake and content.
Week 4
First growth leap (weeks 4-5). More hunger, more crying, more need for arms. Lasts 3-7 days. By the end of this month: the first social smile.
5 things nobody told you about the first month
Baby loses up to 10% of their weight in the first few days — completely normal
Newborns don't have tears until 3-4 weeks
Night duty belongs to both parents — taking turns is what allows survival
Colic has a schedule: it worsens between 4pm and 10pm in almost all babies
You don't need total silence — babies in the womb hear everything. White noise comforts more than silence
The first month changes parents more than the baby. If you feel overwhelmed — it's normal. If you feel you can't handle this, talk to someone. Postpartum depression affects 15-20% of fathers too.
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Week 4: the first social smile. That moment changes everything.
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In the first month, every diaper and every feeding counts. mi·ma logs them in seconds so you can focus on your baby — and have the data ready for every pediatrician visit.
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mi·ma is a support logbook for parents. This guide is informational and does not replace consultation with your pediatrician. For any concerns about your baby's health, consult a healthcare professional.
Sources
- · AAP — Caring for Your Baby and Young Child
- · What to Expect the First Year — Heidi Murkoff
- · Wonder Weeks — Hetty van de Rijt & Frans Plooij