If you're reading this and thinking whether it is true or not, then you are not the first one to be shocked. Pregnancy varies from woman to woman, while some get pregnant without trying and others don't get pregnant even after too many tries. But getting pregnant while you're already pregnant? Seems a little to extreme. This rare phenomenon is known as superfetation. Read on to know more about this.

In this odd phenomenon, a pregnant woman releases an egg a few weeks into her pregnancy. The second egg is fertilised and the woman is then pregnant with two babies simultaneously. But biologically this isn't suppose to happen. Connie Hedmark, a obstetrician in Michigan Hospital told Babycenter, "Pregnancy hormones usually shut down a woman's system, making it impossible for her to ovulate during her pregnancy. This is why superfetation is so remarkable."

The cause of it is however unknown but some believe it occurs when implantation of the first embryo is delayed preventing a spike in hormones. Researchers have so far only been able to find around 10 cases of it happening. In such a case, two babies will be born at the same time, but depending on when the embryos started to grow will depend on the difference between the two. They will be different sizes and have different ages.

In 2011, an Arkansas woman had experienced this phenomenon first hand. After desperate tries for a long time, the couple finally conceived one. However, just two and a half week later, they conceived another - the odds of which are millions to one. She gave birth to both at the same time. She told Mirror Online that in their doctor's 30 years of experience, he'd never seen anything like it.

(The above story first appeared on LatestLY on Jul 20, 2018 11:53 PM IST. For more news and updates on politics, world, sports, entertainment and lifestyle, log on to our website latestly.com).