Superfetation happens if there is a second pregnancy from two separate ovulations; this is usually weeks apart. The second ovulation can occur weeks or even months after the first.

How far apart can superfetation occur?

Risks of Superfetation

Most of the verified cases have been with twins that are only 10 days to three weeks apart, and the reported cases were usually safely delivered.

Can you get pregnant while 3 months pregnant?

And yet – at least for a handful of women – it has happened. In an odd phenomenon known as superfetation, a pregnant woman releases an egg a few weeks into her pregnancy. The second egg is fertilized, and the woman is then pregnant with two babies simultaneously.