Pregnancies and deliveries after injection of vitrified-warmed oocytes with cryopreserved testicular sperm

Successful approach for couples having their own genetic offspring using vitrified-warmed oocytes injected by frozen-thawed poor quality testicular sperm: A case report

The clinical applications of donated gametes are approved in many countries; however, attitudes toward its application and national legislation in some countries are challenging. The purpose of this study is to report a healthy live birth produced by vitrified-warmed oocytes and frozen-thawed testicular sperms to avoid sperm donation.

Failed sperm retrieval from severely oligospermic or non-obstructive azoospermic patients on oocyte retrieval day: Emergent oocyte cryopreservation is a feasible strategy

Purpose

Unexpected sperm retrieval failure on the day of oocyte retrieval is not common but frequently happened in patients with severe oligospermia or non-obstructive azoospermia(NOA). Oocyte cryopreservation is a common strategy after failed collection of sperm when concurrent ovarian stimulation is underwent. However, the use of oocyte vitrification in such male-infertility cases remains unclear.

Objective

To investigate the outcomes of emergent oocyte cryopreservation after failed sperm retrieval from severe oligospermic or non-obstructive azoospermic (NOA) patients on oocyte retrieval day.

Methods

Design: Retrospective cohort study

Setting: Academic fertility center at Lee Women's Hospital, Taiwan, between March 2015 and August 2017.

Patients: For 203 couples with NOA(n = 200) or severe oligospermia(n = 3), testicular spermatozoa (n = 67 cycles) or frozen donor sperm (n = 209 cycles) were injected into fresh or frozen-thawed oocytes via 276 intracytoplasmic sperm injection (ICSI) cycles.

Main Outcome Measures: Clinical pregnancy and live-birth rates (LBRs).

Results

In the 67 cycles involving the use of fresh testicular spermatozoa, no significant differences were observed between fresh and warmed oocytes with respect to the fertilization rates (69.2% vs. 74.1%; p = 0.27), number of Day-3 embryos (8.6±4.4 vs. 6.4±3.4; p = 0.08), number of good-quality Day-3 embryos (4.5±3.9vs. 4.7±3.0; p = 0.45), implantation rates (29.1% vs. 17.8%; p = 0.21), clinical pregnancy rates (36.4% vs. 26.8.0%; p = 0.81), live birth rates (36.4% vs. 14.3%; p = 0.46), or perinatal outcomes. In the 209 cycles involving the use of frozen donor sperm, no significant differences were seen between the two groups, except that the mean birth weights were significantly lower with fresh oocyte pregnancies than with warmed oocytes (2952±196 gm vs 2643±700 gm; p = 0.006).

Conclusions

Emergent oocyte cryopreservation is a feasible strategy to manage unexpected sperm retrieval failure from severe oligospermic or NOA patients on the oocyte retrieval day. There is no detrimental effect on the live birth rate when testicular spermatozoa or frozen donor sperm are injected into the thawed oocytes compared with fresh oocytes.

Effect of different rehydration temperatures on the survival of human vitrified-warmed oocytes

PURPOSE

To evaluate the effect of different exposure temperatures during the dilution process on the survival rate of vitrified oocytes and following development.

METHODS

Patients were divided at random into two groups for different dilution temperature (20-22 °C, RT group; 37 °C,37 °C group) according to computer-generated random numbers on the day of oocyte warming. The survival and fertilization rates of vitrified oocytes as well as the implantation and clinical pregnancy rates of the resulting embryos were recorded.

RESULTS

A total of 662 and 676 oocytes were warmed in the 37 °C group and RT group, respectively, and significant difference was observed in the survival rate between 37 °C group (88.37%) and RT group (79.88%) (P = 0.0000). There was significant difference between the survival rate of 37 °C group (87.27%) and RT group (75.64%) in nondonor patients (P = 0.0001). Multiple linear regression analysis showed that dilution temperature (β = 0.079, P = 0.017) and clinical outcomes of fresh cycles (β = 0.063, P = 0.001) were significantly and independently associated with survival rate. No significant difference was found between the 37 °C group and RT group in: fertilization rate (66.67 versus 65.37%), implantation rate (20.0 versus 19.46%), clinical pregnancy rate (37.5 versus 35.0%).

CONCLUSIONS

In conclusion, the results of this study give supportive evidence of the application of 37 °C in the dilution process, especially for oocytes of poor quality. Further studies with well-controlled experimental groups are needed to optimize protocols for human oocyte vitrification.

Vitrification in human and domestic animal embryology: work in progress

According to the analysis of papers published in major international journals, rapidly increasing application of vitrification is one of the greatest achievements in domestic animal and especially human embryology during the first decade of our century. This review highlights factors supporting or hampering this progress, summarises results achieved with vitrification and outlines future tasks to fully exploit the benefits of this amazing approach that has changed or will change many aspects of laboratory (and also clinical) embryology. Supporting factors include the simplicity, cost efficiency and convincing success of vitrification compared with other approaches in all species and developmental stages in mammalian embryology, while causes that slow down the progress are mostly of human origin: inadequate tools and solutions, superficial teaching, improper application and unjustified concerns resulting in legal restrictions. Elimination of these hindrances seems to be a slower process and more demanding task than meeting the biological challenge. A key element of future progress will be to pass the pioneer age, establish a consensus regarding biosafety requirements, outline the indispensable features of a standard approach and design fully-automated vitrification machines executing all phases of the procedure, including equilibration, cooling, warming and dilution steps.

Birth and clinical pregnancy from fresh and frozen oocytes fertilized with cryopreserved testicular spermatozoa

This is the first report showing a second clinical pregnancy of a couple who already have a baby from a previous frozen embryo transfer cycle when the embryos were generated from fresh oocytes that were fertilized by intracytoplasmic sperm injection (ICSI) using frozen testicular spermatozoa (the couple have unsuccessful fresh and frozen embryo transfer cycles). Fifty-two months after the first IVF/ICSI cycle the couple had their second IVF/ICSI cycle, but the collected oocytes (n=8) were frozen because no spermatozoa was obtained from the frozen testicular tissue samples which were cryopreserved prior to the first IVF/ICSI cycle. New testicular tissue samples were obtained and frozen. Finally, 58 months after the first IVF/ICSI cycle all of the 8 frozen oocytes of the couple were thawed and fertilized by ICSI using frozen testicular spermatozoa obtained from the newly cryopreserved testicular tissue. Three embryos were transferred and the couple has an ongoing pregnancy, which is in the 20(th) week of pregnancy. Our case report shows that: 1) developmentally competent embryos can be generated by ICSI of frozen-thawed testicular spermatozoa into both fresh and frozen human oocytes, and 2) clinical pregnancy and a healthy baby can be conceived from both frozen and fresh oocytes fertilized with cryopreserved testicular spermatozoa.