Evolution of cumulative live birth and dropout rates over six complete IVF/ICSI cycles: a large prospective cohort study.

RESEARCH QUESTION: How do cumulative live birth rates (CLBR), cumulative multiple live birth rates (CMLBR) and dropout rates over six IVF and intracytoplasmic sperm injection (ICSI) cycles change over time? DESIGN: Prospective longitudinal cohort (n = 16,073 patients; 48,946 cycles) starting a first fresh assisted reproductive technology cycle between 1 January 2014 and 31 December 2016, with follow-up until 31 December 2017. Outcomes between the periods 2014-2017 and 2009-2012 were compared. RESULTS: Conservative estimates of CLBR after six complete cycles were significantly higher in women younger than 35 years after every cycle: one to three, adjusted P-value [p adj] < 0.0001; four, p = 0.01; five, p adj = 0.03; six, p adj = 0.04) and after the first cycle in women aged 35-37 years (p adj = 0.04) in 2014-2017 versus 2009-2012. For an optimal estimate, the CLBR was significantly higher after the first three cycles in women younger than 35 years (all p adj < 0.0001) and after the first cycle in women aged 35-37 years (p adj = 0.04). The CMLBR rate decreased from 5.1% ± 0.19 (SE) to 4.1% ± 0.16 for the conservative estimate and from 8.6% ±0.37 (SE) to 6.7% ± 0.30 for the optimal estimate after six complete cycles for the whole cohort. Dropout rates of complete cycles were 26.5% 29.4%, 33.4%, 38.9% and 47.3% after the first to fifth cycle, respectively. Compared with 2009-2012, the dropout rate in the current period was significantly higher for the first (P < 0.0001) and second (P = 0.0124) cycle. CONCLUSION: Over six complete IVF/ICSI cycles, CLBR and dropout rates increased and multiple live birth rates decreased when 2014-2017 was compared with 2009-2012.

The efficacy of the embryo transfer catheter in IVF and ICSI is operator-dependent: a randomized clinical trial.

BACKGROUND: Embryo transfer is a crucial step in the IVF process. Most randomized prospective studies comparing transfer catheters have demonstrated significantly higher pregnancy rates with soft versus firm catheters, but none have taken the operator effect into account. Our aim was to perform a prospective randomized clinical trial comparing two catheters and to study interactions between catheters and operators. METHODS: A prospective randomized trial comparing the Cook K-SOFT-5100 and Frydman classical catheters 4.5 was performed. Three experienced operators participated in the trial, using a fixed distance transfer protocol. Primary end-point was clinical pregnancy rate, secondary end-points were rates of difficult transfer and of catheter failure. Patients were randomized by a computer program prior to embryo transfer. RESULTS: A total of 1446 embryo transfers were performed in 1155 women undergoing IVF or ICSI treatment. A total of 723 cycles were randomized to the Cook catheter and 723 cycles to the Frydman catheter. Following intention-to-treat analysis, the adjusted odds ratio of clinical pregnancy between for the Cook versus the Frydman catheter was 1.11 [95% confidence interval (95% CI) 0.89-1.38]. Odds ratios of clinical pregnancy between the Cook and Frydman catheters for the three operators were respectively 1.19 (95% CI 0.84-1.69), 2.35 (95% CI 1.40-3.95) and 0.69 (95% CI 0.48-0.99). CONCLUSIONS: Variation in pregnancy rates between embryo transfer catheters depends on variation between operators. Results from randomized clinical trials comparing embryo transfer catheters should not be generalized, because inconsistent conclusions may be unavoidable on the account of different proportions of cycles with transfers by each type of operator. The study was registered at clinicaltrials.gov. NCT00766714.