What elite athletes can teach us about pregnancy

( CNN) Serena Williams confirmed Wednesday that she is pregnant with a due date in the autumn. In a Tuesday post on Snapchat, she indicated she is exactly 20 -weeks pregnant, which would entail she was a good two months into her pregnancy in January when she vied in — and won — the Australian Open.

Still, many women are anxious about exercising during pregnancy. This, despite the fact that at the least 18 women have competed in the Olympics while pregnant, according to Sports Reference. Some have done it unknowingly in the earliest days of their pregnancies, while others have participated closer to their due dates than some might believe possible.

The important phase: Not only did these women vie while pregnant, some even won gold medals in the process.