11 weeks pregnant: fetal development

You're getting close to the end of the first trimester. Most of your baby's critical development will be behind you after the next couple of weeks, and the odds of miscarriage will soon drop considerably.

Measuring from head to bottom (crown to rump), your baby is now about 4.1cm, or about the size of a fig (Hill 2019a).

Your baby's face looks more human, as his features take shape and his mouth becomes almost fully formed (Moore et al 2019b, c, Visembryo nd). Inside his mouth, the bones of his palate are fusing (Moore et al 2019a) and his milk teeth are bedding into their sockets (Koussoulakou et al 2009, Moore et al 2019a, Visembryo nd). His fingers may even be growing tiny nails already (Hill 2019b, Moore et al 2019b, NHS 2018, Visembryo nd).

Your baby's veins and arteries are developing (Moore et al 2019a), and they're visible under his thin layer of skin (Moore et al 2019b).

Although his eyes may still be closed, your baby is far from asleep. He's busy flexing his muscles by kicking and stretching (de Vries and Fong 2006), and may have started hiccuping now that his diaphragm is stronger (de Vries and Fong 2006, Lu et al 2016).

You're unlikely to feel these tiny movements, though. Most mums don't feel anything until about 18 to 20 weeks, and it may take longer if this is your first baby (RCOG 2011).

Most of your baby's critical development will tail off in the next couple of weeks. His main task during the next six months will be to grow larger and stronger (Moore et al 2019b), and this includes the rapid growth of his brain (Visembryo nd).

Find out how your life and your body are changing this week with our guide to 11 weeks of pregnancy.