Tamara Vanderent, 30, thought her daughters were fraternal twins for over a year, but she was stunned to discover that wasn't ...

Di-di twins are like roommates with their own room and fridge. They each have their own placenta and amniotic sac – and because they don't share as many resources, they have a lower rate of ...

Little Mix alum Jesy Nelson, who is expecting identical twins with boyfriend Zion Foster, got emotional while discussing her pregnancy complications in a new video.

Conjoined fetuses are a rare type of identical twins that share a placenta and an amniotic sac, when the embryo divides at 13-15 days from conception. The incidence ranges from 1/50,000-1/100,000 ...

A mother gave birth to her son, still in its amniotic sac, at 29 weeks in the front seat of her car Jason Hahn is a former Human Interest and Sports Reporter for PEOPLE. He started at PEOPLE's ...

The fetal membranes consist of the chorion, amnion, yolk sac, and allantois. The chorion has three layers: cytotrophoblastic, chorionic connective tissue, and basement membrane. The chorion lies ...

Amniotic fluid surrounds the growing fetus and provides a ballotable environment that is protective for the fetus. Amniotic fluid also assists in pulmonary development and the avoidance of ...