4 weeks pregnant
Your baby is about the size of a poppy seed.
About 1 mm long. Typical sizes; every baby grows at their own pace.
What’s happening this week
Your baby is a tiny ball of cells that has just settled into the lining of your womb. The sac and the early placenta are starting to form. Most of this week's work is happening quietly, out of sight.
Changes in your body
You may have only just found out, or you may still be waiting to be sure. A missed period is often the first sign. Some women notice light spotting, tiredness or sore breasts, and some feel nothing at all yet.
Book your first doctor's visit
Book a visit with your doctor to confirm the pregnancy. Ask your doctor what you should be taking, and tell them about any medicines you already use.
Bleeding, fluid leaking, fewer baby movements, a bad headache, blurred vision or sudden swelling: call your doctor or hospital now. In an emergency, call 112.
General information, not medical advice. Every pregnancy is different. Reviewed by a Femease doctor.