Second trimester · 15 weeks pregnant
Week 15: sensing light
Legs outgrow arms and the skeleton hardens.
Although the eyelids are still fused, your baby can sense light. The bones are hardening and would show on an X-ray. Hair and eyebrows are starting to grow.
Size and weight
About the size of
an apple
Length
10.1 cm
Weight
70 g
Averages from standard growth charts. Measured crown to rump until week 20 and head to heel afterwards.
How your baby is developing
- The baby senses light through closed eyelids and may move away from a bright torch.
- Legs are now longer than the arms and all joints move.
- Bones harden and the skeleton is visible on ultrasound.
- Scalp hair and eyebrows begin to grow.
How you may feel
- A stuffy nose (pregnancy rhinitis) and snoring
- Bleeding gums
- Heartburn and indigestion
- Occasional headaches
- Steady weight gain beginning
Typical weight gain in the second and third trimesters is about 0.4 to 0.5 kg a week for someone who started at a healthy weight. Your care provider will advise what is right for you.
What's next
Tests and appointments
- If the first screening placed you in a risk group, the regional Mother and Child Screening centre performs second-stage tests at 16–20 weeks: ultrasound, blood tests and, when needed, invasive diagnosis with genetic analysis.
- Amniocentesis is offered from 15 weeks only when there is a specific reason.
What to do this week
- Prop your head up at night and try saline spray for the stuffy nose.
- Floss gently and brush with a soft brush; see a dentist if gums bleed a lot.
- Eat smaller meals and avoid lying down straight after eating to limit heartburn.
Call your doctor or maternity hospital if
- Any vaginal bleeding, or fluid leaking from the vagina
- Regular, painful tightenings or period-like cramps
- A severe headache, blurred vision, or sudden swelling of your face and hands
- Severe or persistent abdominal pain, fever, or pain when you pass urine
If something feels wrong, trust yourself and call 103 or your maternity hospital. You will never be wasting anyone's time.
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