João Michelon

Successful birth after injection of frozen human oocytes with frozen epididymal spermatozoa

A couple (female 31, male 42 years old) with infertility due to obstructive azoospermy returned to the clinic in order to attempt pregnancy using their frozen oocytes and epididymal sperm cells, which had been cryopreserved at the time of a previous IVF attempt. Two days before the scheduled transfer, eight oocytes were thawed; 5/8 (63%) oocytes survived and 4/5 (80%) oocytes fertilized after intracytoplasmic sperm injection (ICSI) with the previously frozen epididymal spermatozoa. All four fertilized ova cleaved (100%). On day 2 after thawing, four embryos were transferred; three with two cells (grade II) and one with three cells (grade III). Hormonal support for the established pregnancy was maintained with oestradiol and progesterone orally until 12 weeks of gestation, and the patient was delivered by Caesarean section at 40 weeks of gestation; the baby boy weighed 3025 g, and measured 51 cm, with Apgar of 10 in the 1st and 5th min. The cryopreservation and warming protocol used for this study yielded very favourable results, comparing well with reports in the literature. This case report demonstrates that it is possible to obtain high rates of oocyte survival following thawing and high rates of fertilization after ICSI, with viable development of the resulting embryos.

Comparison of embryo quality between sibling embryos originating from frozen or fresh oocytes

Human embryo cryopreservation techniques allow storage of surplus embryos created during assisted reproduction procedures; however, the existence of these same surplus embryos has sparked further debate. What can be their fate once they are no longer desired by their parents, or if the parents are deceased? Thus, the level of interest in the cryopreservation of oocytes has increased, as has the necessity for further scientific study. This study had the objective of comparing embryo quality from 16 women who underwent intracytoplasmic sperm injection, where approximately half of the retrieved oocytes per cycle were inseminated fresh after collection, and the remainder cryopreserved for subsequent fertilization. Normal fertilization rates were not significantly different between the two oocyte-treatment groups. There was no significant difference in the frequency of good quality embryos (morphology grades I and II) on the second day of laboratory evaluation between embryos derived from the two oocyte-treatment groups. It is interesting to note that embryo transfer from fresh oocytes produced no pregnancies, which shows that even embryos derived from frozen oocytes that are fragmented or have a slower cleavage rate are viable embryos, capable of producing healthy babies.

Experience of freezing human oocytes using sodium-depleted media

Human embryo cryopreservation techniques enable the storage of surplus embryos created during assisted reproduction procedures; however, the existence of these same surplus embryos has sparked further debate. What can be their fate once they are no longer desired by their parents or if the parents are deceased? Thus, the level of interest in the cryopreservation of oocytes has increased, as has the necessity for further scientific study. This study had the objective of reporting 10 years of experience of freezing and thawing human oocytes from patients who did not wish to freeze embryos. A total of 159 cycles using frozen–thawed oocytes were performed (mean age 33.7 years). Survival and fertilization rates were 57.4% and 67.2%, respectively. Cleavage rate was 88.4% and the pregnancy rate was 37.7%. Clinical pregnancy was observed in 43 cycles (27.0%) with 14.5% of transferred embryos implanted. These pregnancies delivered 19 boys and 23 girls, two pregnancies are ongoing and nine were miscarriages. The average gestational week was 37.6 weeks and birthweight was 2829.2 g. These data suggest that the use of frozen–thawed oocytes in IVF represents a reasonable alternative for those patients not comfortable with the cryopreservation of supernumerary embryos.

Análise da coagulação sangüínea em pacientes submetidas à hiperestimulação ovariana para fertilização in vitro

BACKGROUND: Hyperestrogenic conditions have been related to alterations in the coagulation parameters. The objective of this study was to identify changes in coagulation parameters in women undergoing in vitro fertilization and embryo transfer (IVF-ET). METHODS: A group of 15 patients was studied prospectively, immediately before and during the course of an IVF-ET cycle. Blood was drawn in the preovulatory period of the cycle preceeding IVF-ET for complete blood count, fibrinogen, prothrombin time (TP), thromboplastin partial actived time (ATTP), coagulation time and estradiol. A another blood sample for the same tests was collected during controlled ovarian hyperstimulation, on the hCG day. Both samples were compared by a paired t-test RESULTS: There was an increase in fibrinogen (340.9 pg/mL to 383.1 pg/mL, p = 0.01). On the other hand, hematocrit levels decreased (40.5% to 38.4 %, p = 0.0001). The other coagulation tests showed no difference. Estradiol levels increased (167 pg/mL to 1435 pg/ml, p=0.0001), as expected during such treatment. CONCLUSIONS: The data suggest a tendency towards an increase in coagulability, as expected in hyperestrogenic situations. However, even considering the statistical significance of the results, they might have limited clinical impact, since they were within the normal range. This study suggests that, despite the marked increase in estradiol and changes in coagulation parameters, IVF-ET is a safe procedure in terms of thromboembolic risks.