Day 200 of 280, third trimester
You are 28 weeks and 4 days
Your baby's growth depends on many factors, and its rate varies through pregnancy.
80 days until your due date
Your baby's growth relies on a steady stream of nutrients. Most cross the placenta unchanged, but some are made by the placenta and a few by your baby. These include the hormone thyroxine, which depends on iodine from you crossing the placenta. Thyroxine has several jobs and its level must be precisely controlled, and the placenta forms an almost perfect barrier to it, so you and your baby can adjust your levels independently.
Early on, genes largely determined your baby's size, but now environmental factors matter more. Overall, birth weight is determined about 40 percent by genes and 60 percent by environment. Your baby grows steadily from 24 weeks until the last 2–3 weeks, when growth continues more slowly. (Twins grow as if alone until 28 weeks, then more slowly.) Much of the current growth is in the internal organs, especially the liver and brain, and muscle mass is increasing. Later, fat will be laid down under the skin, rounding out your baby's shape.
Focus on
Twins: Buying for your twins
Twins' clothes should be easy to put on and take off and machine washable. You'll probably be given outfits as presents, so just buy the basics.
For each baby, you're likely to need at least:
- Six undershirts
- Six onesies
- Two jackets
- One or two hats (a sun hat in summer)
- Several burp cloths and bibs
Twins are often smaller at birth than single babies, so you may go through a range of diaper sizes in the first few months. Buy a good-quality double stroller, since it will be used for a long time; a side-by-side model is better than a tandem, so your babies can see and communicate with each other as they grow.
As a matter of fact
More twins
The number of twin births jumped 66 percent between 1980 and 2003.
Triplet and higher births increased fourfold over the same period. Twins are born, on average, 17 minutes apart.
Appointments and key dates around now
- Whooping cough vaccineUsually around 20 weeks, best before 32 weeks
- RSV vaccineFrom 28 weeks
Read the full 28 weeks pregnant guide
This is general information based on NHS guidance, not medical advice, and every pregnancy is different. Talk to your midwife or GP about anything that worries you. If your baby's movements slow down or change, or you have bleeding, severe pain or leaking fluid, call your maternity unit straight away. In an emergency, call 999.