You are now
You are now
The foetal sac is now the size of a hen's egg. The foetus inside is three centimetres long - the size of a jelly baby! Some of the chorionic villi will now disappear, leaving others to grow and become the placenta. Eyes and ears develop rapidly at this time, and the beginnings of the skeleton are present. Your baby's heart has four chambers and beats twice as fast as yours. Muscles are developing so a scan would now show real movement. Amazing.
See how your baby grows in our week by week image gallery.
Top button of your jeans tricky to fasten? You may have noticed a slight thickening of your waistline. Don't blame it on the baby, yet! The foetus only weighs four grams, or maybe an eighth of an ounce. It's probably just fluid retention. Remember to keep popping those folic acid supplements - current advice is to keep them going until you're 12 weeks. And hopefully, if you were a smoker, you're now well on the road to a smoke-free life - for you and your baby.
Pregnancy health: protecting your baby from tobacco smoke is one of the best things you can do. Cigarettes restrict oxygen supply to your baby, so their heart has to beat harder every time you smoke. Second-hand smoke can cause low birth weight and cot death. Also, babies whose parents are smokers are more likely to be admitted to hospital for bronchitis and pneumonia during the first year of life. You can get free help and advice on how to stop smoking. Talk to your midwife or health visitor or call the NHS Pregnancy Smoking Helpline on 0800 169 9169.
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