Effect of double embryo transfer derived from autologous frozen oocytes on multiple pregnancy rates and presentation of success rates stratified by age at retrieval

Objective:

To compare outcomes transferring one or two embryos in autologous frozen oocyte cycles.

Material and Methods:

A retrospective cohort study conducted at an academic fertility center between January 2012 and December 2018. One-hundred and fourteen patients underwent frozen oocyte transfers; 67 single embryo transfer (SET) and 47 double embryo transfer (DET). No subjects had more than two embryos transferred. Data were analyzed using t-test and chi-squared testing. Multivariate logistic regression was used to control for confounding effects. Power analysis suggested an 82% power with alpha of 5% and effect size of 27%.

Results:

Regarding the embryo stage, 72% were cleavage embryos and 28% were blastocyst embryos. Among those who had cleavage stage embryos, 48.8% underwent SET and 51.2% underwent DET. In the blastocyst embryos group these proportions were 84.4% and 15.6%, respectively. There were no difference in pregnancy rate for SET (40.3%) vs DET (36.2%) (p=0.78). Additionally, the live birth rate did not differ between SET and DET (28.4 vs 19.1%, respectively, p=0.26). The multivariate multilevel analysis provided adjusted odds ratios (95% confidence interval) of: 1.85 (0.46-7.44) for pregnancy; 0.497 (0.05-4.86) for clinical pregnancy; and 0.82 (0.11-6.29) for live birth when comparing SET and DET. Multiple pregnancy rates were significantly lower in the SET (0%), compared with DET group (44.4%) (p<0.002).

Conclusion:

SET results in excellent live birth outcomes in autologous frozen oocyte cycles. However DET results in significantly increased rates of multiple pregnancies. This suggests that SET is a viable option in autologous frozen oocyte cycles.

Single and double embryo transfer provide similar live birth rates in frozen cycles

Research question: Do live birth rates (LBRs) differ in frozen cycles of women who received single versus double embryo transfer?Design: Retrospective cohort study including women who underwent their first frozen embryo transfer (FET) in a tertiary referral University Hospital between 2009-2014.Results: 3601 patients were included in the analysis with 1936 (53.8%) having a single embryo transfer (SET) and 1665 (46.2%) having a double embryo transfer (DET). Overall, 657/3601 (18.24%) had a live birth. LBR were similar between SET and DET either for cleavage [100/757 (13.1%) versus 153/1032 (14.8%), p = .33] or blastocyst stage FET [256/1179 (21.7%) versus 148/633 (23.4%), p = .4). Ongoing pregnancy rates were comparable between DET and SET [316/1665 (18.9%) versus 359/1936 (18.5%)]. Multiple delivery rates were significantly higher in women with DET compared to SET [53/316 (16.7%) versus 7/359 (1.9%), p < .001]. Multivariate logistic regression analysis allowing adjustment for relevant confounders showed that the number of embryos transferred in the frozen cycle was not related to LBR.Conclusions: This is the largest study providing evidence that both SET and DET may result in similar LBR, albeit multiple pregnancy rates are significantly lower in case of SET. Therefore, SET should be the main strategy in women undergoing FET.

Impact of government health coverage for ART: The results of a 5-year experience in Quebec

An analysis of national registry data for 5 years of in-vitro fertilization (IVF) funding in Quebec, Canada was compared with the previous complete year of non-funded IVF cycles, as well as the first complete year following the end of funding. The number of cycles, livebirth rates, age group of patients treated, use of donor gametes, multiple pregnancy rates and cycle cancellation rates were assessed. The total number of IVF cycles performed increased dramatically during the funded period, averaging over 10,000 cycles per year. There was no change in the age group distribution of patients treated, but less egg donation was performed. Interestingly, funding was also associated with an increase in the IVF cycle cancellation rate (17.0% versus 34.4%, P < 0.001), a dramatic decline in the multiple pregnancy rate (25.6% versus 4.9%, P < 0.001), and a decline in the livebirth rate per fresh embryo transfer in stimulated IVF cycles (32.3% versus 25.5%, P < 0.001). Although the livebirth rate for stimulated IVF declined, over 9000 babies were born as a result of the coverage. Lessons learned from this experience could help develop a more fiscally responsible programme that still facilitates access to IVF care.