According to a retrospective analysis of data collected on major birth defects associated with ART (assisted reproductive technology), overall birth defect rates are down but remain high compared to those reported after natural conception.

Birth defect reports were studied in 213,908 women. Assisted technology was used in 2,911 pregnancies with the remaining 210,997 birth resulting after natural conception.

In 8.7% of assisted pregnancies, major birth defects were reported compared to 5.4% of natural pregnancies. Researchers also studied the twin population with 7.1% of assisted conception resulting in twin pregnancies reporting major birth defects compared to 5.9% of B/G twins conceived naturally. Birth defects in both groups were reported by age six.

Overall birth defects in the study population, which was taken from Western Australia, decreased compared to previous years, but reports of major birth defects remained higher in the assisted pregnancy group compared to the natural pregnancy group for both singlets and twins.

Source: Hansen M, Kurinczuk JJ, de Klerk N, Burton P, Bower C. Assisted reproductive technology and major birth defects in Western Australia. Obstet Gynecol. 2012 Oct; 120(4):852-63.