Experience with a patient-friendly, mandatory, single-blastocyst transfer policy: the power of one.

OBJECTIVE: To determine whether a mandatory single-blastocyst transfer (mSBT) algorithm reduced multiple gestation rates without sacrificing clinical pregnancy rates. DESIGN: Retrospective review. SETTING: U.S. university-based assisted reproductive technology (ART) program. PATIENT(S): All women younger than 38 years undergoing their first ART cycle from 2009 to 2010 with ≥4 high-grade embryos on day 3 after oocyte retrieval (patients from 2009 were the "before" group, and patients completing ART under the mSBT policy in 2010 were the "after" group). INTERVENTION(S): mSBT algorithm. MAIN OUTCOME MEASURE(S): Multiple gestation and clinical pregnancy rates. RESULT(S): Of the qualified patients, 136 women met inclusion criteria (62 from 2009, 74 from 2010). The baseline demographics were similar between the groups. Statistically significantly fewer blastocysts were transferred per patient in 2010 compared with 2009 (1.5 vs. 1.9). The clinical pregnancy rates before (67.7%) or after (63.5%) the mSBT policy were not statistically significantly different. Multiple gestation rates were statistically significantly reduced, from 43.8% (2009) to 14.6% (2010) after the mSBT policy was instituted. More patients from 2010 had ≥1 blastocyst cryopreserved compared with 2009 (52.9% vs. 30.6%). CONCLUSION(S): A novel single-blastocyst transfer algorithm reduced multiple gestation rates and improved cryopreservation rates without compromising clinical pregnancy rates in good-prognosis patients.

Blastocyst development rate impacts outcome in cryopreserved blastocyst transfer cycles.

OBJECTIVE: To assess cycle outcome among day 5 and day 6 cryopreserved frozen-thawed blastocyst embryo transfers (FBET). DESIGN: Retrospective cohort study. SETTING: Military-based assisted reproduction technology (ART) center. PATIENT(S): One hundred seventy-two nondonor, programmed cryopreserved embryo cycles. INTERVENTION(S): Fully expanded blastocysts on day 5 were cryopreserved on day 5, and those achieving this state on day 6 were cryopreserved on day 6. Leuprolide acetate was given for ovulation inhibition, and endometrial supplementation was by oral and vaginal estradiol. Progesterone in oil was administered, and blastocyst transfer occurred in the morning of the sixth day of progesterone. MAIN OUTCOME MEASURE(S): Implantation, pregnancy, and live-birth rates. RESULT(S): Fresh and frozen cycle characteristics were similar between groups. Day-5 FBET had statistically significantly higher implantation rates (32.2% vs. 19.2%), which remained significant even when adjusting for covariates (odds ratio: 1.91; 95% confidence interval, 1.00, 3.67). Live-birth rates trended toward improvement after adjusting for covariates (odds ratio: 1.18; 95% confidence interval, 0.61, 2.30). CONCLUSION(S): Cryopreserved day-5 blastocysts have higher implantation rates and trend toward improved pregnancy outcomes compared with cryopreserved day-6 blastocysts. This suggests that embryo development rate may, in part, predict implantation and subsequent FBET outcomes, although embryos not achieving the blastocyst stage until day 6 still demonstrate acceptable outcomes.

The limited importance of pronuclear scoring of human zygotes.

BACKGROUND: Several studies have shown a correlation between the pronuclear morphology score (PNMS) and subsequent embryo development and implantation. Embryos with poor pronuclear score, elsewhere referred to as Z3 and Z4, are often not transferred or cryopreserved because it is believed that they have poor pregnancy potential. The objective of this study is to report our data on the use of the pronuclear score and its effect on pregnancy outcome. METHODS: Retrospective analysis of IVF/ICSI-embryo transfer cycles completed over the course of 1 year (n = 334). Comparisons were made only in those groups of patients in whom cohorts of similarly scored PNMS embryos were transferred. The proportion of such homologous cohorts was 104/334 (31%). All other replacements were excluded from final analysis as they were dissimilar as far as PNMS is concerned. Pregnancy outcomes were evaluated. RESULTS: The incidence of live birth resulting from the transfer of single pronuclear score homologous embryo types was 56 (14/25), 41 (13/32), 54 (23/43) and 0% (0/4) for PNMS scores 1, 2, 3 and 4, respectively. There was no correlation between PNMS category of the embryos transferred and live birth rates (P = 0.139). CONCLUSIONS: PNMSs of 1, 2 or 3 do not correlate with live birth rates when assessing unique PNMS embryo transfers. In particular, previously considered poor (type 3) embryos can result in pregnancy with normal live birth rates. Whether type 4 embryos are compatible with normal development remains to be shown.

Embryo afterloading: a refinement in embryo transfer technique that may increase clinical pregnancy.

OBJECTIVE: Given the importance of ET technique during assisted reproductive technology cycles, we evaluated the effect of embryo afterloading subsequent to placement of the ET catheter on pregnancy rates vs. a standard direct ET. DESIGN: Retrospective cohort analysis. SETTING: University-based assisted reproductive technology program. PATIENT(S): Patients undergoing a fresh nondonor day 3 ET by a single provider over a 1-year period. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Clinical pregnancy. RESULT(S): One hundred twenty-seven patients met inclusion criteria, and the overall pregnancy rate was 46.5%. There was no difference between the two groups with respect to age, basal FSH, or number of embryos transferred. The ET method used was at the discretion of the provider. There was no difference between the two groups in the presence of blood on the transfer catheter. However, there were significantly more transfer catheters with mucus contamination in the direct transfer group (25.58% vs. 5.95%). The clinical pregnancy rate in the group with ET using the afterloading technique was higher than in the direct ET group (52.4% vs. 34.9%). CONCLUSION(S): There was a trend toward an increase in pregnancy rate when an embryo afterloading technique was used. A prospective randomized trial is needed to examine this issue.