Elective Single Cleavage-Stage Embryo Transfer in IVF Patients with Suboptimal Ovarian Response is Not Detrimental to Cumulative Pregnancy and Reduces Multiple Pregnancy Rates.

Purpose: To evaluate whether elective single embryo transfer in patients with suboptimal response to ovarian stimulation is detrimental to pregnancy rates compared to double embryo transfer. Methods: A case-control retrospective study was performed in a cohort of couples undergoing IVF at the Infertility Unit of the ASST Lariana with ≤ 9 oocytes and at least 2 viable embryos. A total of 424 women were analyzed in the "double embryo transfer" group (n = 212) and elective "single embryo transfer" group (n = 212); they were matched 1:1 for female age, ovarian reserve and number of previous cycles. Cumulative clinical pregnancy rate per oocyte retrieval was the main outcome. Results: The cumulative pregnancy rate per cycle, including the fresh embryo and subsequent frozen embryo transfers, was 26% and 26%, respectively. Considering the main confounding factors, a binomial logistic model indicated that the cumulative clinical pregnancy rate was not significantly affected when a single embryo transfer was performed in women recovering up to nine oocytes. Conclusion: Live birth rate was similar between the two groups, while twin pregnancies were significantly reduced in women receiving single embryo transfer suggesting that elective single embryo transfer in patients with a limited number of embryos is not detrimental to pregnancy rates.

Pregnancy rate in IVF patients with unexpected poor response to ovarian stimulation.

OBJECTIVE: To evaluate whether an unexpected poor response (cases with ≤3 oocytes) leads to a reduction in the pregnancy rate in IVF cycles compared to a suboptimal response (controls with 4-9 oocytes) in women with adequate ovarian reserve. METHODS: A nested case-control study performed in a retrospective cohort of couples undergoing IVF at the Infertility Unit of the ASST Lariana. Cases and controls had adequate ovarian reserve and were matched 1:1 for female age and number of previous cycles. Cumulative clinical pregnancy rate per oocyte retrieval was the main outcome. RESULTS: Overall, 113 cases and 113 matched controls were included; the median number of available oocytes was 2 and 6, respectively. The cumulative pregnancy rate per cycle was significantly reduced in cases compared to controls with a crude odds ratio = 0.45 [95% Confidence Interval: 0.28-0.82]. A binomial logistic model indicated that an increase in one oocyte increases the odds for cumulative pregnancy rate per cycle by 1.27 in women with 9 oocytes or less. The cumulative pregnancy rates per cycle in cases and controls, according to female age were respectively: 29% versus 54% in patients aged <35 years (p = 0.036); 22% versus 43% in patients aged 36-39 years (p = 0.048) and 11% versus 13% in patients 40-45 years old (p = 0.72). Patients belonging to older age groups showed decreasing probability of cumulative clinical pregnancy rates both among cases and controls group (p < 0.05). CONCLUSIONS: The number of available oocytes significantly affects the probability of success in IVF cycles with unexpected impaired ovarian response.

Can We Prepare IVF Culture Media Two Days Before Ovum Pick up Without Affecting Embryological Parameters? A Retrospective Case-Matched Study.

BACKGROUND: According to several laboratory protocols and specific conditions, in vitro fertilization (IVF) dishes with culture media can be prepared 24 hr in advance compared to routine protocols. However, it is not clear if this procedure can affect embryological outcomes. METHODS: A nested case-control study was done in a cohort of couples undergoing IVF at the Infertility Unit of the ASST Lariana from August 2016 to July 2018. Cases were patients undergoing ovum pick up after a laboratory day off. Controls were patients undergoing ovum pick up after working days from Monday to Thursday. Culture media for oocyte culture and insemination were prepared about 42 and 18 hr before oocyte retrieval for cases and controls, respectively. Cases and controls were matched with a 1:2 ratio (for age, inseminated oocytes, length of stimulation). The "Good-Quality-Index" (GQI) was the main outcome to be compared between the two groups and was defined as good quality transferred or cryopreserved embryos on day 2 or 3+number of good quality blastocysts/inseminated oocytes. RESULTS: A total of 76 cases and 152 matched controls were enrolled. The median GQI was equal to 33.0% (IQR: 20.0-50.0%) and 33.0% (IQR: 25.0-50.0%), in cases and controls, respectively (p=0.40). Study groups and GQI were not significantly correlated (correlation coefficient r=0.047, p=0.48). Main embryological parameters and cumulative pregnancy rates were similar between the two groups. CONCLUSION: Our data support the vision that culture media can be prepared 24 hr in advance compared to routine protocols without affecting embryological outcomes.