Aneuploidy in first trimester pregnancy loss following in vitro fertilization and intracytoplasmic sperm injection

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OBJECTIVE: The literature on pregnancy outcomes after intracytoplasmic sperm injection (ICSI) is limited and inconclusive concerning the risk of miscarriage and aneuploidy. ICSI bypasses natural selection mechanisms and could potentially lead to higher aneuploidy rates in embryos through both procedure dependent and independent pathways. We sought to compare the aneuploidy rate in first trimester pregnancy losses with regards to patients undergoing ICSI or conventional insemination at the time of IVF. DESIGN: Retrospective cohort analysis. MATERIALS AND METHODS: All patients undergoing IVF cycles at an academic IVF center from January 2000 to December 2006 were included. All patients had a first trimester pregnancy loss followed by evacuation of the pregnancy and karyotyping of the abortus. The main outcome measure was rate of aneuploidy following Conventional IVF (n=159) and ICSI (n=196). The study population's demographics were similar for both groups; semen parameters as expected varied significantly between the groups. RESULTS: A significant increase in fetal aneuploidy rate was noted with increasing maternal age (<30 years = 26.1 % vs. 31 to 34 years. = 38.2 % vs. 35 to 39 years. = 51.3% vs. >39 years. = 65.9 %). There was no difference in aneuploidy rates for conventional IVF vs. ICSI for each maternal age group. Overall aneuploidy rates were similar in the ICSI vs. conventional IVF group (52.6 % vs. 47.2% (p 0.31, RR 1.11, 95% CI 0.90, 1.38)). Six sex chromosome anomalies were noted in the ICSI group vs. none in the conventional IVF group. Autosomal trisomy was the most common aneuploidy in both groups. Among abortuses with normal cytogenetic results, female karyotype was found three times more frequently then male karyotype in both groups. This finding may represent predominance of maternal cells in culture or absences of products of conception in the sample. CONCLUSIONS: The aneuploidy rate in first trimester abortuses significantly increases with increasing maternal age. ICSI was not shown to significantly increase the aneuploidy rate. However, more sex chromosome anomalies were found among pregnancies resulting from ICSI.