Week seventeen often sits in the thick of the four-month sleep change, and teething can begin. A demanding but playful stretch. Here is what is normal.
Typical day · week 17
- Feeds: 6 to 8 milk feeds in 24 hours
- Sleep: 14 to 16 hours across day and night
- Naps: 3 to 4 naps, wake windows of 1.5 to 2 hours
- Diapers: 5 to 6 or more wet per day
Feeding
Feeding is settled, breast or bottle, and still milk-only; solids are a few weeks off yet. If teething has started, some babies feed a little fussily for a day or two around a tooth and then settle. Keep following appetite, and steady diapers and weight remain your reassurance that intake is fine.
Sleep
This is the heart of the four-month sleep change for many families: if longer stretches have suddenly given way to waking every one to two hours, this is why, and it is a permanent maturing of sleep rather than a true regression. More daytime activity and tummy time help, as does putting your baby down drowsy but awake when you can. Above all, protect your own sleep where possible and treat it as a phase that passes.
Diapers
Steady output, with softer breast stools and firmer formula stools as before. Loose stools for more than 24 hours, especially alongside any illness, are worth watching for dehydration.
Growth
Steady weight gain continues on the growth curve. Your baby grabs at everything within reach with real intent and shows clear favorites among people, toys and games.
This week's leap
Awake time is increasingly fun: frequent laughing, extended back-and-forth play, and clear preferences. Teething can begin any time from now, lower front teeth first; some babies show no symptoms, others are visibly uncomfortable for a few days. Offer a chilled (not frozen) teething ring, and infant acetaminophen at the right dose can ease genuine pain.
From three months, a fever of 101.3°F (38.5°C) or above warrants assessment. Teething itself does not usually cause a real fever, so a temperature alongside teething signs is worth a call to rule out an ear infection. Diarrhea beyond 24 hours, a seizure, breathing difficulty, or a non-blanching rash needs prompt or urgent attention, and if sleep deprivation is harming your own wellbeing, ask for support rather than pushing through alone. None of this is medical advice; every baby is different, and your midwife, health visitor or doctor is the person to ask about your own child.
The calm way to follow all of this is to log it in one tap as it happens, then read the pattern over a few days rather than carrying it in your head. Little Bean shows this same week-by-week guidance inside the app, beside your own baby's log.
Quick answers: 17 weeks
How often should a 17-week-old eat?
Most babies this age take 6 to 8 milk feeds in 24 hours. Feed on demand rather than by the clock; steady weight gain and enough wet diapers are the real signs intake is fine.
How much sleep does a 17-week-old need?
Roughly 14 to 16 hours across day and night. 3 to 4 naps, wake windows of 1.5 to 2 hours. The range is wide, so treat these as averages rather than targets.
What are typical wake windows at 17 weeks?
3 to 4 naps, wake windows of 1.5 to 2 hours. An overtired baby fights sleep harder, so watch the clock and the tired signs together.
Milestone reference: CDC developmental milestones, 4 months checklist.
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