Li Z, et al. - In this population-based study, researchers investigated the cumulative live birth rate following ICSI cycles vs IVF cycles for couples with non-male factor infertility. They found that the cumulative live birth rate provided by ICSI was similar to that obtained with IVF for couples with non-male factor infertility.

Methods

• Researchers performed a retrospective analysis of a population-based cohort of 14 693 women, who had their first ever stimulated cycle with fertilization performed for at least one oocyte by either IVF or ICSI between July 2009 and June 2014 in Victoria, Australia.
• After IVF or ICSI, they recorded the pregnancy and birth outcomes for the first oocyte retrieval (fresh stimulated cycle and associated thaw cycles) until 30 June 2016, or until a live birth was achieved, or until all embryos from the first oocyte retrieval had been used.
• They gathered data on demographic, treatment characteristics and resulting outcome from the Victorian Assisted Reproductive Treatment Authority.
• The VARTA dataset comprised data items collected from all fertility clinics in Victoria.
• Based on having undergone IVF or ICSI, women were grouped.
• The cumulative live birth rate, which was defined as live deliveries (at least one live birth) per woman after the first oocyte retrieval, was the primary outcome.
• They used a discrete-time survival model to assess the cumulative live birth rate following IVF and ICSI.
• The adjustment was made for the following factors: the year of treatment in which fertilization occurred, the woman’s and male partner’s age at first stimulated cycle, parity and the number of oocytes retrieved in the first stimulated cycle.

Results

• A total of 7980 and 13,092 embryo transfers were performed in 4993 women undergoing IVF and 8470 women undergoing ICSI, resulting in 1848 and 3046 live deliveries, respectively.
• During the study period, about one-fifth of the women (19.0% of the IVF group vs 17.9% of the ICSI group) underwent three or more cycles.
• In both IVF (range: 4.2–66.5) and ICSI group (range: 4.5–71.3) (P=0.474), 8.9 months was estimated to be the median time from oocyte retrieval to live delivery for couples who achieved a live delivery.
• In the IVF vs in the ICSI group, a higher fertilization rate per oocyte retrieval was observed (59.8 vs 56.2%, P < 0.001).
• For IVF and for ICSI, the observed overall cumulative live birth rate was 37.0% and 36.0%, respectively.
• Compared with women undergoing IVF, no significantly different overall likelihood of a live birth was reported for women undergoing ICSI (adjusted hazard ratio (AHR): 0.99, 95% CI: 0.92–1.06).
• Findings reported non-male factor infertility (female factor only or unexplained infertility) for 64.0% in the IVF group and 36.8% in the ICSI group (P < 0.001) for couples with a known cause of infertility.
• A similar cumulative live birth rate was provided by ICSI vs IVF among couples with non-male factor infertility (AHR: 0.96, 95% CI: 0.85–1.10).