Association of birth defects with the mode of assisted reproductive technology in a Chinese data-linkage cohort.

<bold>Objective: </bold>To evaluate the impact of assisted reproductive technology (ART) on the offspring of Chinese population.<bold>Design: </bold>Retrospective, data-linkage cohort.<bold>Setting: </bold>Not applicable.<bold>Patient(s): </bold>Live births resulting from ART or natural conception.<bold>Intervention(s): </bold>None.<bold>Main Outcome Measure(s): </bold>Birth defects coded according to ICD-10.<bold>Result(s): </bold>Births after ART were more likely to be female and multiple births, especially after intracytoplasmic sperm injection (ICSI). ART was associated with a significantly increased risk of birth defects, especially, among singleton births, a significantly increased risk in fresh-embryo cycles after in vitro fertilization (IVF) and frozen-embryo cycles after ICSI. Associations between ART and multiple defects, between ART and gastrointestinal malformation, genital organs malformation, and musculoskeletal malformation among singleton births, and between ART and cardiac septa malformation among multiple births were observed.<bold>Conclusion(s): </bold>This study suggests that ART increases the risk of birth defects. Subgroup analyses indicate higher risk for both fresh and frozen embryos, although nonsignificantly for frozen embryos after IVF and for fresh embryos were presented with low power. Larger sample size research is needed to clarify effects from fresh- or frozen-embryo cycles after IVF and ICSI. [ABSTRACT FROM AUTHOR]