Identical (monozygotic) twins develop from a single egg-sperm combination that splits into two. If the split is delayed, usually a week or so after conception, the processes of growing a placenta, ...

Twins—smaller at birth, on average, than singletons—start out smaller in pregnancy than was previously known, according to a study by researchers at the National Institutes of Health (NIH). The ...

Mono-mono twins are an incredibly rare type of identical twins who share both a placenta and an amniotic sac. While this ...

Being pregnant with twins can be exciting for many women, but the risks associated with multiple pregnancies can be frightening, particularly in Nigeria, where the healthcare system remains fragile, ...