Multivariate analysis of factors affecting probability of pregnancy and live birth with in vitro fertilization: an analysis of the Society for Assisted Reproductive Technology Clinic Outcomes Reporting System

Objective: To evaluate factors predictive of clinical pregnancy and of pregnancy loss from assisted reproductive technology (ART) using data from the Society for Assisted Reproductive Technology database for 2004-2006.

Design: Retrospective cohort.

Setting: Clinic-based data.

Patient(s): The study population included 225,889 fresh embryo transfer cycles using autologous oocytes and partner semen.

Intervention(s): None.

Main outcome measure(s): Clinical intrauterine gestation (presence of gestational sac) and live birth (>or=22 weeks gestation and >or=300 g birth weight).

Result(s): Increasing maternal age was significantly associated with a reduced odds of conception and increased fetal loss until 19 weeks gestation, but not with later pregnancy loss. Intracytoplasmic sperm injection (ICSI), assisted hatching, and increasing number of embryos transferred had significant positive effects on the odds of conception and pregnancy continuation through the first trimester, but did not affect the risk of later loss. Blacks, Asians, and Hispanics had significantly lower odds of clinical pregnancy compared with whites. Also compared with whites, Hispanics and Asians had a significantly greater risk of pregnancy loss in the second and third trimesters, and blacks had a significantly greater risk of pregnancy loss in all trimesters.

Conclusion(s): Certain demographic and ART treatment parameters influenced chance of conception and early pregnancy loss, whereas black race and Hispanic ethnicity were also significantly associated with late pregnancy loss in ART-conceived pregnancies.