Superfetation is so rare there are only a handful of reported cases. Three extremely...
More about 'twins'
A woman got pregnant while already pregnant, and delivered 'super twins' on the same day
Anna Medaris Miller, Business Insider US
Doctors have identified a rare pair of 'semi-identical' twins. Here's how that might happen.
Doctors in Australia say they identified semi-identical twins who share all of their...
Caroline Praderio, Business Insider US