First trimester: weeks 1to12
You’re pregnant: congratulations! The first weeks of your pregnancy are a vital time as your body gets busy building a baby. How exciting!
First trimester: key stages
The first trimester begins on the first day of your last period and lasts until the end of week 12. This means that by the time you know for sure you’re pregnant, you might already be five or six weeks pregnant!
A lot happens during these first three months. The fertilized egg rapidly divides into layers of cells and implants in the wall of your womb where it carries on growing. These layers of cells become an embryo, which is what the baby is called at this stage.
During this trimester, your baby grows faster than at any other time. By six weeks, a heartbeat can usually be heard and by the end of week 12, your baby’s bones, muscles and all the organs of the body have formed. At this point, your baby looks like a tiny human being and is now called a fetus. He or she will even be practicing swallowing!
Find out more about the first trimester
- 4 weeks pregnant – all you need to know Congratulations on your exciting news!
- 9 weeks pregnant – all you need to know Measuring about 22mm long, your baby is now as big as a strawberry.
- 10 weeks pregnant – all you need to know Your uterus is the size of a large orange now, and your baby is around 3cm long
- 11 weeks pregnant – all you need to know You’re now coming up to the end of the first trimester and your baby is starting to look like a baby! Your bump may start to show soon.
12 weeks pregnant – all you need to know It’s been a busy few weeks: Everything is now in place – the organs, limbs, bones and muscles are in place and growing
IDEAL MOMMY 