Longer term risks and in vitro fertilization
- Multiple pregnancy
Having twins doubles or triples most birth-related risks to you and babies. Transferring one embryo at a time almost eliminates the risk of twins, but not quite, because the chance of identical twins is higher after in vitro fertilization than from natural conceptions. Around 2% of all births at Fertility Associates after transfer at one in vitro fertilization embryo are identical twins. Identical twins carry a higher risks of complications for the children.
For some people there is a remote risk of multiple pregnancy resulting from the fertilization of an egg not retrieved during egg collection in addition to the embryo(s) transferred.