Second trimester · Month 4 of 9

Week 16: A growing uterus and changing balance

You may notice stretching sensations as the uterus grows; sudden severe or persistent pain needs assessment.

Month 4 · Week 1624 weeks to the due-date marker
Month4 of 9
Week16
PeriodSecond trimester
This monthA new stretch

In 60 seconds

Your short plan for this week

Do now

Learn the difference between a brief stretching twinge and pain that is severe, persistent, rhythmic or paired with bleeding or fever.

Coming up

Vaccination recommendations can depend on season and location; ask what is currently recommended rather than relying on an old list.

Pause and ask

Do not self-diagnose abdominal pain from its location alone—call when pain is strong, worsening or comes with other warning signs.

What you may notice

Your body and how you may feel

You may notice stretching sensations as the uterus grows; sudden severe or persistent pain needs assessment.

What is happening

Baby’s development this week

Facial expressions and limb movements are developing, even if you cannot feel them yet.

Plain-language examples

What this means in real life

Round-ligament discomfort is often brief and linked to movement; that label should not be used to explain away new severe pain.

A short checklist

What to do now

  • Learn the difference between a brief stretching twinge and pain that is severe, persistent, rhythmic or paired with bleeding or fever.
  • Stay active in ways that feel stable and are appropriate for your pregnancy.
  • Learn what movement changes should prompt a call later in pregnancy.

Pause and check

What not to do—or what to ask first

  • Do not self-diagnose abdominal pain from its location alone—call when pain is strong, worsening or comes with other warning signs.
Check food, medicines, exercise and everyday activities →

What may be coming up

Appointments, tests and decisions

Vaccination recommendations can depend on season and location; ask what is currently recommended rather than relying on an old list.

Common planning window

Review pregnancy vaccinations

Confirm current and seasonal recommendations with your clinician.

Common planning window

Understand screening choices

Ask what each screening test can and cannot tell you before deciding.

For the support person

One useful thing a partner can do

  • Slow down sudden changes of direction, offer a hand on stairs if wanted, and take pain reports seriously.

Contact your care team

Contact your doctor or maternity team promptly

Some concerns need advice before the next routine appointment even when they do not feel like an emergency. If a symptom becomes severe, sudden or frightening, use urgent care instead.

See when to contact care

Urgent or emergency

Urgent signs during pregnancy or within a year after birth

Get medical care immediately for these symptoms. The list is not exhaustive; if something feels seriously wrong, seek help.

Open urgent warning signs