16 weeks pregnant
At 16 weeks you are in the second trimester, and your baby measures about 12 cm from crown to rump and weighs about 100 g, roughly the length of an avocado. The 16-week antenatal visit is this week, and some people feel the first flutters of movement from now, usually later in a first pregnancy.
Weighs about 100 g, like a bar of soap. Averages from standard growth tables; your scan gives your baby's own numbers.
Your baby at 16 weeks
The eyes move and the ears are in position; the baby hears muffled sounds. The body is catching up with the head, the face looks human and movements are becoming coordinated.
How you might feel
Backache and round-ligament twinges can start as the uterus grows, and many people describe the middle weeks as the most comfortable of the pregnancy.
16-week visit. Some people feel first flutters from now, often later in a first pregnancy.
Call your maternity unit or GP today for bleeding, severe pain, or if you cannot keep fluids down. 13 HEALTH (13 43 25 84) in Queensland; 000 in an emergency.
What's due this week in Australia
Hospital booking-in visit
Usually at 12–16 weeks, about an hour with a midwife.
Tell your employer (when you are ready)
There is no legal deadline to tell your employer, but protections start once they know: transfer to a safe job, no-safe-job leave and special maternity leave.
16-week antenatal visit
Review of the first-trimester results, blood pressure, the baby’s heartbeat and a referral for the morphology scan.
Coming up: Morphology (anatomy) ultrasound
A detailed 30–60 minute scan of the baby’s organs, spine, heart and limbs, the placenta position and the cervix.
Coming up: Whooping cough (pertussis) vaccine
Free under the National Immunisation Program in every pregnancy.
Checklist for the week
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Questions about 16 weeks
How many months is 16 weeks pregnant?
About three and a half months.
What trimester is 16 weeks?
Week 16 is in the second trimester. In the Australian guidelines Hello Bub follows, the first trimester runs to 13 weeks, the second from 14 to 27 and the third from 28 weeks.
When will I feel the baby move?
Usually between 16 and 22 weeks. First pregnancies tend to be later, around 18 to 22 weeks, because the early flutters are easier to recognise the second time.
Written by the Hello Bub team; medical schedule follows the Australian Pregnancy Care Guidelines; last reviewed 3 November 2026.