One of the most fascinating things about your pregnancy is watching your baby grow, and fetal development during the first trimester is perhaps the most amazing time to do so. While the vast majority of external changes happen later on in your pregnancy, it’s that first trimester fetal development that is most significant for your baby. This is why the first trimester is usually considered the most crucial in terms of your baby’s health and well-being.
One of the first things to remember when you’re looking at fetal development during the first trimester is that each baby is different. That being said, there are still specific milestones that your doctor is going to be looking for, and that you can watch for, as well.
By about the sixth week of your pregnancy, you’re going to be able to detect the heartbeat of your fetus using a vaginal ultrasound. This may happen later for some babies, so if it doesn’t happen right away at six weeks you probably don’t need to be alarmed. You may also be able to detect what is known as a “fetal pole” at six weeks. This is the smallest version of your baby you’re going to be able to see, and it will in some ways look a lot like a tadpole.
At seven weeks, you should be able to see the beating of the fetus’ heart on a regular ultrasound. Over the following few weeks, you’ll be able to watch as your baby’s organs start to develop. By the time you hit the two month mark, your baby is going to be around the size of a kidney bean, and is going to be moving around quite a bit. There will be distinct, webbed fingers, as well.
Over the remaining part of the first trimester, fetal development is marked, as well. Your baby is going to grow to the point where she’s about three inches in length, and she’s even going to develop her own fingerprints.