Weird as it may sound, it is true — you can get pregnant while you are already pregnant. The phenomenon is known as superfetation or sometimes referred to as superfoetation. The condition can occur when more than one fetus develop in a female during the same menstrual cycle, at different intervals. In such pregnancies the babies are conceived at different times and are born at the same time often just moments apart but are not considered twins.
The incidence of this phenomenon is very high in some species of animals, though only some cases have been seen in humans. Total recorded number of cases worldwide is currently 11, last of which was seen here in America, in the state of Arkansas.
Mr Todd and his wife Mrs Julia Grovenburg were in for a surprise in mid 2009, when Julia became pregnant twice within two weeks, after what seemed to them a long battle to conceive children. This was a shock to not only them but also their doctor who had never seen anything like it before in his 30 years of clinical practice. The babies were born healthy and at the same time though the boy Hudson, who was conceived later, was born before his sister Jillian who was the older one, medically.
In any pregnancy, the conception occurs when sperm fertilizes the egg in a woman’s womb during the peak days of her ovulation in a menstrual cycle. In a normal pregnancy the woman stops ovulating after the fertilized egg ends up implanting itself in the uterus. This is a natural mechanism to ensure a full term pregnancy and favorable pregnancy outcomes. But in case of superfetation, the ovulation continues (ovaries keep on producing more mature eggs) and further intercourse can result into a subsequent pregnancy.
The one prominent risk of the pregnancy in such cases is that the fetus conceived at a later time is born prematurely and is thus at an increased risk of lung development problems.