A comparison of perinatal outcomes in singletons and multiples born after in vitro fertilization or intracytoplasmic sperm injection stratified for neonatal risk criteria.

Objective: To compare perinatal singleton and multiple outcomes in a large Dutch in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) population and within risk subgroups. Newborns were assigned to a risk category based on gestational age, birthweight, Apgar score and congenital malformation.

Design: Register-based retrospective cohort study.

Long term costs and effects of reducing the number of twin pregnancies in IVF by single embryo transfer: the TwinSing study.

Background: Pregnancies induced by in vitro fertilisation (IVF) often result in twin gestations, which are associated with both maternal and perinatal complications. An effective way to reduce the number of IVF twin pregnancies is to decrease the number of embryos transferred from two to one. The interpretation of current studies is limited because they used live birth as outcome measure and because they applied limited time horizons.