The window is wide: flexible timing for vitrified-warmed embryo transfer in natural cycles.

RESEARCH QUESTION: What is the optimal timing for transfer in natural cycle vitrified-warmed embryo transfers (NC-VET)? DESIGN: This retrospective cohort study uses data from a large university-affiliated IVF clinic. The study included 341 NC-VET cycles with autologous oocytes and non-preimplantation genetic testing, vitrified embryos from January 2013 to September 2017. Each cycle was classified by timing of embryo transfer in relation to LH surge ≥20 IU/l. Group 1: LH ≥20 IU/l one day and blastocyst was transferred 6 days later; Group 2: LH ≥20 IU/l two consecutive days and blastocyst was transferred 6 days after the initial surge; Group 3: LH ≥20 IU/l two consecutive days and blastocyst was transferred 7 days after the initial surge. The primary outcome was ongoing pregnancy rate (OPR). The secondary objective was to compare OPR in relation to serum oestradiol dynamics and progesterone concentration (according to threshold 1.0 ng/ml) 6 days prior to embryo transfer. RESULTS: OPR were similar for all three groups (66.8%, 65.0%, 62.9% for Groups 1, 2 and 3, respectively). When stratified according to oestradiol and progesterone, no significant differences were noted in OPR. CONCLUSIONS: The results suggest that the timing of blastocyst transfer in a natural cycle after LH surge is flexible within 24 h. Outcomes are equally good with day of embryo transfer 6 or 7 days after LH surge date. Oestradiol dynamics and progesterone concentration 6 days prior to NC-VET did not have a significant impact on OPR.

An Evidence-based Approach to the Medical Management of Fibroids: A Systematic Review.

Fibroids are the most common tumor of the female reproductive tract, but approved medical treatments are limited. Patients demand uterine-sparing treatments which preserve fertility and avoid surgery. We systematically reviewed PubMed and Cochrane databases from January 1985 to November 2015 for evidence-based medical therapies for fibroids in the context of disease prevention, treatment of early disease, treatment of symptomatic disease, and preoperative management. We identified 2182 studies, of which 52 studies met inclusion and exclusion criteria. Published data affirm the efficacy of multiple agents, which are promising avenues for the development of medical alternatives to surgery.

Improvement of RNA secondary structure prediction using RNase H cleavage and randomized oligonucleotides.

RNA secondary structure prediction using free energy minimization is one method to gain an approximation of structure. Constraints generated by enzymatic mapping or chemical modification can improve the accuracy of secondary structure prediction. We report a facile method that identifies single-stranded regions in RNA using short, randomized DNA oligonucleotides and RNase H cleavage. These regions are then used as constraints in secondary structure prediction. This method was used to improve the secondary structure prediction of Escherichia coli 5S rRNA. The lowest free energy structure without constraints has only 27% of the base pairs present in the phylogenetic structure. The addition of constraints from RNase H cleavage improves the prediction to 100% of base pairs. The same method was used to generate secondary structure constraints for yeast tRNA(Phe), which is accurately predicted in the absence of constraints (95%). Although RNase H mapping does not improve secondary structure prediction, it does eliminate all other suboptimal structures predicted within 10% of the lowest free energy structure. The method is advantageous over other single-stranded nucleases since RNase H is functional in physiological conditions. Moreover, it can be used for any RNA to identify accessible binding sites for oligonucleotides or small molecules.

In vitro fertilization outcomes after preimplantation genetic testing for chromosomal structural rearrangements comparing fluorescence in-situ hybridization, microarray comparative genomic hybridization, and next-generation sequencing.

OBJECTIVE: To compare in vitro fertilization (IVF) outcomes for preimplantation genetic testing for chromosomal structural rearrangements (PGT-SR) using various testing platforms. DESIGN: Retrospective cohort. SETTING: Large academic IVF center. PATIENTS: Fifty-one balanced translocation carriers undergoing IVF with PGT-SR who completed a total of 91 cycles, including 31 fluorescence in-situ hybridization (FISH), 24 microarray comparative genomic hybridization (aCGH), and 36 next-generation sequencing (NGS) testing cycles. INTERVENTIONS: PGT-SR. MAIN OUTCOME MEASURES: Primary outcome of live-birth rate and secondary outcomes including implantation rate, clinical loss rate, and percentages of normal or balanced, unbalanced, and aneuploid embryos detected. RESULTS: There was no statistically significant difference in LBR, though there was a tendency toward a higher LBR for NGS testing (14 of 19, 73.7%) compared with FISH (8 of 18, 44.4%) and aCGH (10 of 20, 50.0%). The implantation rate was statistically significantly higher for NGS (16 of 20, 80.0%) compared with FISH (11 of 25, 44.0%) and aCGH (16 of 30, 53.3%). There was no statistically significant difference in clinical pregnancy losses. There was a lower percentage of normal or balanced embryos with FISH (12.5%) compared with aCGH (23.7%) and with NGS (20.7%). CONCLUSIONS: This is the first report of PGT-SR outcomes for translocation carriers directly comparing PGT-SR using FISH, aCGH, and NGS. Our findings suggest an improvement in pregnancy outcomes parallel to the advancement in technology and are reassuring for continued use of NGS for this population.