16 weeks pregnant
Second trimester about 3 months
At 16 weeks pregnant, your baby is about the size of an avocado.
Baby this week
About 115mm. The fetus is making coordinated limb movements and can hear muffled sounds from outside the womb. The heart pumps about 25 liters of blood per day.
Did you know? By week 16, the fetus's heart is pumping approximately 25 liters of blood per day — a remarkable feat for an organ barely the size of a walnut.
What she may be feeling
- Quickening — fluttery baby movements
- Growing belly
- Back pain
- Round ligament pain
- Heartburn
- Nasal congestion
- Possible nosebleeds (increased blood volume)
- Skin changes — glow or hyperpigmentation
Tips for her this week
- NIPT results including sex (if you chose to find out) may arrive around now.
- Quickening — first baby movements — often begins this week, especially for first-time moms.
- Your blood volume has increased by about 45% — this can cause dizziness if you stand up too quickly.
- Schedule your anatomy scan for week 20 if you haven't already.
For partners
- If you had NIPT testing, sex results may be available now — decide together if you want to know.
- Play music near her belly — babies respond to sound and will recognize familiar music after birth.
- The anatomy scan is coming up at week 20 — put it in the calendar and make it a priority to attend.
- Start researching pediatricians — you'll want one selected before the baby arrives.
Partner to-do list
- Decide together if you want to know the sex from NIPT results
- Plan a gender reveal or sex announcement moment if desired
- Research pediatricians in your area
- Confirm anatomy scan is booked for week 20
This week together
- Find out or decide not to find out the sex
- Book the anatomy scan
- Start shortlisting pediatricians
- Plan a babymoon if you haven't yet — the window is weeks 14–24
When to call your doctor or midwife
Contact your care provider right away, or call emergency services, if she has:
- Heavy bleeding
- Severe cramps
- Fever
- Regular tightening or contractions
Trusted guidance: NHS: Pregnancy · NHS: Pregnancy complications · ACOG: Pregnancy · Pregnancy Info: Your pregnancy
Common questions
How big is the baby at 16 weeks?
At 16 weeks pregnant, your baby is about the size of an avocado. About 115mm.
How many months is 16 weeks pregnant?
16 weeks pregnant is about 3 months, in the second trimester.
What can partners do at 16 weeks?
If you had NIPT testing, sex results may be available now — decide together if you want to know. Play music near her belly — babies respond to sound and will recognize familiar music after birth.