Assisted reproductive technologies and the risk of congenital urogenital tract malformations: A systematic review and meta-analysis.

A systematic review was conducted to evaluate the relationship between ART and the risk of urogenital tract malformations, especially hypospadias and cryptorchidism. Thirty-three papers were selected. Meta-analysis showed that ART was correlated with an increased risk of urogenital tract malformation in offspring (odds ratio (OR) = 1.61, 95% confidence interval (CI): 1.41-1.85), hypospadias (OR = 1.87, 95% CI: 1.47-2.40) and cryptorchidism (OR = 1.83, 95% CI: 1.54-2.18). Among offspring conceived by ART, multiple pregnancies appeared to result in a higher risk of urogenital tract malformation than singleton pregnancies (OR = 1.42, 95% CI: 0.99-2.04; P = 0.058). No significant difference in the risk of urogenital tract malformation was found between in vitro fertilization and intracytoplasmic sperm injection technologies. A sensitivity analysis showed that the above conclusions were relatively consistent. Conclusion: ART is correlated with an increased risk of urogenital tract malformations in offspring, especially hypospadias and cryptorchidism. Among ART offspring, multiple pregnancies may lead to a higher risk of urogenital tract malformations than singleton pregnancies, but more studies are needed for confirmation.