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 ...

A twin pregnancy is when there are two fetuses in the uterus at the same time. Twins can be identical, meaning they developed when a single fertilized egg split early in development, or fraternal, ...

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, ...