Congenital anomalies after assisted reproductive technology.

Worldwide, more than 5 million children have been born after assisted reproductive technology (ART), and in many developed countries ART infants represent more than 1% of the birth cohorts. It is well known that ART children are at increased risk of congenital malformations even after adjustment for known confounders such as maternal age. The proportion of ART children is not negligible, and knowledge about the causes of the higher risk of congenital malformations is crucial to develop prevention strategies to reduce the future risk in ART children. The aim of this review is to summarize the literature on the association between ART and congenital anomalies with respect to subfertility, fertility treatment other than ART, and different ART methods including intracytoplasmic sperm injection, blastocyst culture, and cryotechniques. Trends over time in ART and congenital anomalies will also be discussed.