Use of ICSI in IVF cycles in women with tubal ligation does not improve pregnancy or live birth rates.

STUDY QUESTION: Does ICSI improve outcomes in ART cycles without male factor, specifically in couples with a history of tubal ligation as their infertility diagnosis?

SUMMARY ANSWER: The use of ICSI showed no significant improvement in fertilization rate and resulted in lower pregnancy and live birth (LB) rates for women with the diagnosis of tubal ligation and no male factor.

WHAT IS KNOWN ALREADY: Prior studies have suggested that ICSI use does not improve fertilization, pregnancy or LB rates in couples with non-male factor infertility. However, it is unknown whether couples with tubal ligation only diagnosis and therefore iatrogenic infertility could benefit from the use of ICSI during their ART cycles.

STUDY DESIGN, SIZE, DURATION: Longitudinal cohort of nationally reported cycles in the Society for Assisted Reproductive Technology Clinic Outcomes Reporting System (SART CORS) of ART cycles performed in the USA between 2004 and 2012.

PARTICIPANTS/MATERIALS, SETTING, METHODS: There was a total of 8102 first autologous fresh ART cycles from women with the diagnosis of tubal ligation only and no reported male factor in the SART database. Of these, 957 were canceled cycles and were excluded from the final analysis. The remaining cycles were categorized by the use of conventional IVF (IVF, n = 3956 cycles) or ICSI (n = 3189 cycles). The odds of fertilization, clinical intrauterine gestation (CIG) and LB were calculated by logistic regression modeling, and the adjusted odds ratios (AORs) with 95% confidence intervals were calculated by adjusting for the confounders of year of treatment, maternal age, race and ethnicity, gravidity, number of oocytes retrieved, day of embryo transfer and number of embryos transferred.

MAIN RESULTS AND THE ROLE OF CHANCE: The main outcome measures of the study were odds of fertilization (2PN/total oocytes), clinical intrauterine gestation (CIG/cycle) and live birth (LB/cycle). The fertilization rate was higher in the ICSI versus IVF group (57.5% vs 49.1%); however, after adjustment this trend was no longer significant (AOR 1.14, 0.97-1.35). Interestingly, both odds of CIG (AOR 0.78, 0.70-0.86), and odds of LB were lower (AOR 0.77, 0.69-0.85) in the ICSI group. Plurality at birth, mean length of gestation and birth weight did not differ between the two groups.

LIMITATIONS, REASONS FOR CAUTION: This was a retrospective study, therefore only the available parameters could be included, with parameters of interest such as smoking status not available for inclusion. Smoking status may have led practitioners to use ICSI to improve pregnancy and LB outcomes.

WIDER IMPLICATIONS OF THE FINDINGS: Studies have shown that in the USA there is an increasing usage of ICSI for non-male factor infertility despite a lack of evidence-based benefit. Our study corroborates this increasing use over the last 8 years, specifically in the tubal ligation only patient population. Even after adjusting for multiple confounders, the patients who underwent ICSI had no statistically significant improvement in fertilization rate and actually had a lower likelihood of achieving a clinical pregnancy and LB. Therefore, our data suggest that the use of ICSI in tubal ligation patients has no overall benefit. This study contributes to the body of evidence that the use of ICSI for non-male factor diagnosis does not improve ART outcomes over conventional IVF.

STUDY FUNDING/COMPETING INTERESTS: None.