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Pregnancy at 4 Weeks

Pregnancy at 4 Weeks

If you haven’t already, go ahead and schedule that first prenatal appointment. While you’re on the phone, ask for a prenatal vitamin recommendation, and find out whether the medications you’re currently taking are safe for your baby.

Start taking your prenatal vitamins, if you haven’t already, and continue to avoid drugs, alcohol and excessive caffeine. About 150 mg of caffeine per day is the safe limit according to the American Pregnancy Association, if any. You’ll want to stay away from all three during your pregnancy.

Your Body at 4 Weeks Pregnant

Your embryo has reached your uterine cavity and is starting to form roots, a process called implantation. You might experience some mild spotting or implantation bleeding, which is very common. Yes, it’s worrying to see any kind of blood this early in your pregnancy, but this spotting doesn’t usually mean that you’re having a miscarriage. In fact, a third of pregnant women will experience this kind of bleeding. Contact your health care provider if the bleeding is more than light spotting.


Estrogen levels in your body are slowly rising, and you might start noticing some mild breast tenderness. Most women, however, will not notice any change in the way their bodies feel. In fact, at this early stage, it’s very common for women not to feel pregnant at all. Even if you’re already pregnant, the main pregnancy hormone known as Human Chorionic Gonadotropin (HCG), will take a while to reach a high enough level in your blood stream and urine to be detected. The earliest you can usually detect HCG in your blood stream is two weeks from ovulation, which is usually four weeks from the beginning of your last missed period.

Your Baby at 4 Weeks Pregnant

At this point, implantation is complete and your embryo is getting plenty of nutrients and oxygen from you. A primitive blood circulation is getting established in your growing embryo. The cells that make up your embryo are starting to change into many different types of cells. This will enable the embryo to eventually develop into a baby with all its different parts. At this point, your baby is the size of a single grain of rice!


The preceding information was adapted from The Pregnancy Companion.

Image Source: iStock Photo

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