Updated: Mar 12, 2019
Being Pregnant is amazing. Not only does your body change to meet the demands of growing baby inside you, but also it all takes place in just 40 weeks.
As you uterus expands, so does your bump. The distance from pubis to the top of the uterus is measured regularly from the second trimester of pregnancy. It's called the fundal height and is monitored as a marker of fetal growth. The measurement in centimetres usually matches the week of pregnancy that you are in.
1 - 4 weeks
During the early weeks your baby is no bigger than the size of a grain of rice, so your uterus has only started on its growth spurt alongside your baby's.
At four weeks, your uterus is pretty much the same size as before you were pregnant (about the size of a plum) and it measures between 6-10cm (2.5-4in) in length (not height as it is horizontal).
9 - 12 weeks
At this stage your baby is about the size of a lime. You might notice that you need to pass urine more often as your growing uterus puts pressure on your bladder.
Frequent urination can also be a sign of a urinary infection, so speak to your GP if it is painful when you pee. Your hands and feet may feel warmer because of the increased blood flow to your skin.
17 - 21 weeks
Your baby is roughly the size of a mango at the point of gestation. Your uterus has grown upwards and is now level with the height of your belly button.
As your bump becomes more visible people might start to notice that you are pregnant, they might even want to touch your bump.
27 - 30 weeks
Your baby is now about the size of a squash. Your fundal height at 30 weeks is 30cm (12in). The wall of the uterus is muscular and during pregnancy it enlarges to many times its original dimension. By 30 weeks it has tripled in size.
36 - 40 weeks
At the very end of your pregnancy your baby is on average 51.2cm (20.16in) - similar to a medium-size watermelon. Your fundal height peaks at about 36 weeks and measures 36cm (14in). You might find that your bump is a bit of a load at this stage as it makes simple tasks tricky.