By the end of 12 weeks, your uterus is too large to remain completely in your pelvis. You may feel it above your pubic bone. If this is your first pregnancy, you may still be able to squeeze into your regular clothes, but if you have had other pregnancies you are likely to be into your maternity wardrobe by now. During pregnancy the uterus grows upwards to fill the pelvis and abdomen and returns to its normal, pre-pregnancy state within a few weeks after delivery. Before pregnancy your uterus is almost solid but during pregnancy it changes into a comparatively thin-walled, muscular container big enough to hold the fetus, placenta and amniotic fluid. It increases its capacity 500 to 1000 times during pregnancy. The weight also changes; when your baby is born your uterus weighs almost 40 oz (1.1kg) compared to 2½ oz (70gm) before pregnancy. The uterine wall grows in size due to hormonal stimulation while the baby and the placenta stretch and thin the uterine wall.

You are more cautious these days. For instance you avoid walking across slippery roads; you avoid eating 'leftovers' lying in the fridge you are not too sure about. While it is worthwhile to be careful, you don't want to not enjoy your pregnancy by being paranoid. Take the necessary precautions but don't allow yourself to become engulfed by anxiety. That is not healthy for you or your baby.