Superfetation. You may have never heard that word before as it is a very rare occurrence. Superfetation is when you become pregnant when you are already pregnant. Yes, you read that correctly. It actually is possible to become pregnant while you are already pregnant. But how is this possible? It’s quite simple actually.

Ovulation

As you are likely aware, ovulation is what happens to fertile women every month. The ovaries produce eggs that move through the fallopian tubes to the uterus and attaches to the uterine wall. That egg just sort of hangs out waiting to be fertilized, but when that doesn’t happen the uterine wall sloughs off, taking the egg with it.

Then a brand new uterine wall and brand new egg replace the old and the cycle repeats itself every month. You may refer to this cycle as a “period”, and this keeps a fresh egg in place to be fertilized every month.

Pregnancy stops ovulation

Well, this cycle is supposed to stop when a surrogate mother undergoes the procedure to carry a child for someone else, but on rare occasions it doesn’t. Because of this it is possible for a woman’s own egg to enter the uterus during an existing pregnancy, and then that egg can be fertilized through sexual intercourse.

Generally once the surrogate egg is fertilized and the woman becomes pregnant, this monthly cycle stops. However such as like in nature, sometimes things don’t always go exactly how they are supposed to.

Doctors are still not certain exactly how this happens. Usually surrogacy is involved, a surrogate mother is carrying for someone else and then becomes pregnant with their own child through conventional means. It must occur early in the pregnancy otherwise hormones will prevent it from happening.

But with surrogacy many fertility drugs and hormones are given to increase the chances of pregnancy occurring and so this makes the woman extra fertile. So with all the rare occurrences lined up just right, it can happen, and does, although rarely.