Successful use of "Hour 1" transfer of sperm microinjected oocytes in natural cycles of poor responder women: a prospective randomized controlled pilot study.

The aim of the study is to demonstrate the successful use of "Hour 1" transfer of sperm microinjected oocytes in natural cycles of poor responder women. Seventy women were selected from 92 consecutive poor responders undergoing intracytoplasmatic sperm injection (ICSI) in a natural cycle at our Sterility and Assisted Reproduction Unit from September 2009 to July 2013, and randomly distributed in two homogeneous groups: Group A or B. Women in Group A (35) underwent transfer within 1 h after ICSI; Group B (35, control group) underwent transfer 3 days after ICSI. In Group A, seven clinical pregnancy and one miscarriage occurred; in Group B, eight clinical pregnancies and two miscarriages were observed. Pregnancy, miscarriage, term pregnancy and overall live birth rates' difference between the two groups was not statistically significant (p > 0.05). Difference between the two groups in terms of timing, type of delivery and newborn birthweight was not observed. Neither ectopic pregnancy nor multiple pregnancies occurred. "Hour 1" uterine transfer of ICSI oocytes, still to be considered with caution because of the relatively low number of observations of the pilot study, deserves further attention on a larger scale, and might be evaluated for clinical and financial effectiveness in other clinical settings.

Term pregnancy and live birth subsequent to immediate uterine transfer of sperm microinjected oocyte in a natural cycle.

It has been reported that it is possible to achieve a pregnancy after immediate uterine transfer of oocyte and sperm, before fertilization and cleavage were known to have occurred; there is an enormous amount of work about the optimal timing of embryo transfer, with no conclusive evidence of a gold standard satisfying patient age, endometrial receptivity, hormonal levels and embryological parameters. We hereby report a case of one 35-year-old nulligravid woman with longstanding tubal factor infertility and 3 previous failed ICSI cycles, treated with ICSI and immediate transfer of the oocyte microinjected with a spermatozoon in a natural cycle. A single oocyte was retrieved, injected with a spermatozoon and transferred 40 min after injection, resulting in an uneventful pregnancy and delivery of a healthy female infant weighing 3320 g at 40 weeks' estimated gestational age. This case, certainly novel, should be interpreted with caution. Whether confirmed for efficacy and safeness in appropriate controlled clinical trials, our present observation could offer a simple, practical and cost-effective approach in ART programs in selected patients.