Number of transferred embryos: how to reduce multiple pregnancies

'Two countries-two labs': the transnational gamete donation (TGD) programme to support egg donation

PURPOSE

To evaluate the effectiveness, efficiency, and safety of a transnational gamete donation (TGD) programme based on the shipping of vitrified donor oocytes.

METHODS

A retro-prospective observational study was conducted in the Assisted Reproductive Technology Center of the University Hospital of Florence, Italy. The study population included 622 consecutive donor oocyte cycles. A mean number of 6 vitrified oocytes per couple were shipped from two Spanish biobanks. In the receiving centre, gametes were warmed and inseminated and the subsequent embryo transfer (ET) was performed. The main outcome measurement was LBR. Secondary outcomes included oocyte survival rate, ICSI damage rate, normal fertilization, cleavage, and implantation rate (IR) in both 'fresh' and cryotransfer cycles.

RESULTS

A total number of 3536 mature oocytes were warmed with 81.4% surviving oocytes. 2PN oocytes were 1941 with an ICSI normal fertilization rate of 70.4% and a cleavage rate of 93.4%; 857 day-3 embryos were transferred in 498 women, 63 blastocysts in 44. Couples with at least one vitrified embryo were 181 (32.3%). IR was 25.1% and 33.1% for day-3 ET and blastocyst stage respectively. Crude pregnancy rate and LBR after the first ET were 35.5% and 27% correspondingly with a conservative cumulative LBR of 34% and an optimal LBR of 51.4%.

CONCLUSION

Imported vitrified donor oocytes retain their competence and are capable of resulting in ongoing pregnancies and healthy babies in a proportion comparable to other existing systems as egg donation with vitrification/warming in the same laboratory and transnational fresh oocyte donation.

Association between the number of oocytes retrieved and cumulative live birth rate in women aged 35-40 years undergoing long GnRH agonist IVF/ICSI cycles

PURPOSE

To study the association between the numbers of oocytes retrieved and the cumulative live birth rates (LBR) in women aged 35-40 years undergoing long GnRH agonist IVF/ICSI cycles.

METHODS

A total of 931 women aged 35-40 years who underwent their first cycle of IVF/ICSI treatment between January 2010 and December 2013 at Nanjing Drum Tower Hospital were identified and reviewed. The main endpoint of this study was the cumulative LBR after one complete oocyte retrieval, which included fresh and all subsequent frozen-thaw embryo transfer cycles. Odds ratios (OR) and 95% confidence interval (CI) for live birth were estimated by multivariate logistic regression analysis. Furthermore, all the women were divided into four groups based on the number of oocytes retrieved: 0-4, 5-9, 10-14 or ≥15 oocytes group. Variables were then compared among groups.

RESULTS

We found that 634 out of the 931 patients (68.1%) achieved at least one live birth. The number of oocytes retrieved was an independent predictive factor for live birth, with OR 1.20 (95% CI 1.15-1.26) when adjusted for age (years), duration of infertility and Gn (gonadotrophin) doses. The cumulative LBR in the four different oocyte groups was 35.6, 68.8, 83.4 and 89.2%, respectively. When the 1-4 oocytes group was issued as a reference, the ORs for cumulative LBR gradually increased to 3.66, 6.74 and 11.77 in other three oocytes groups, respectively. The moderate-severe ovarian hyperstimulation syndrome (OHSS) rate was dramatically increased in the ≥15 oocytes group (6.9%) when compared to that in the 10-14 oocytes group (0.8%), while the cumulative LBR only increased 5.8% (from 83.4 to 89.2%).

CONCLUSIONS

The ideal number of oocytes retrieved in women aged 35-40 years is 10-14 oocytes, which achieves a high cumulative LBR while maintaining an acceptable low OHSS rate.

LIF and sIL-2R plasma concentrations in IVF patients on the day of embryo transfer: predictive markers of IVF outcome

Successful implantation is still the limiting step in IVF. We hypothesized that maternal plasma concentrations of certain cytokines at the time of embryo transfer could predict the likelihood of successful implantation and pregnancy. sIL-2R, IL-6, LIF, and MMP2 concentrations were measured in plasma from 160 IVF patients (natural and stimulated IVF cycles) on the morning of the embryo transfer (ET0) and 14 days later (ET+14). Patients were ultimately subdivided into four groups depending on the IVF treatment outcome (pregnancy failure, biochemical pregnancy, first-trimester miscarriage and normal term delivery). In natural and stimulated IVF cycles at ET0, sIL-2R concentrations were threefold higher in biochemical pregnancies than in pregnancy failures (P=0.020), and in natural cycles only, 2.5-fold higher in normal term deliveries than in pregnancy failures (P=0.023). Conversely, in natural and stimulated IVF cycles at ET0, LIF concentrations were one third lower in biochemical pregnancies/first-trimester miscarriages compared with pregnancy failures (P=0.042). We suggest that high sIL-2R and low LIF concentrations in maternal plasma on the morning of the embryo transfer might be associated with increased risks of early pregnancy loss, while a basal level of sIL-2R is necessary for normal term delivery outcome. Both cytokine measurements might therefore be useful in the management of IVF patients, and modulation of their concentrations could be investigated as a therapeutic alternative for women with abnormal concentrations at the time of embryo transfer.

Elective transfer of two embryos: reduction of multiple gestations while maintaining high pregnancy rates

PURPOSE

To determine if the elective transfer of two embryos reduced the incidence of multiple gestations while maintaining high pregnancy rates.

METHODS

IVF patients and recipients of oocyte donation with an elective day-3 transfer of 2 or 3 embryos were studied.

RESULT(S)

In IVF, the elective transfer of 2 embryos resulted in similar pregnancy rate but significantly reduced the overall incidence of multiple gestations (20% versus 39%) when compared to the elective transfer of 3 embryos. Twin gestations decreased from 28% to 19%, and triplets significantly decreased from 9% to 1%. In oocyte donation, the elective transfer of 2 embryos resulted in similar pregnancy rate but also significantly reduced the overall incidence of multiple gestations (26% versus 48%), with twins decreasing from 34% to 24%, and with a significant reduction of triplets (13% versus 2%).

CONCLUSIONS

In IVF and oocyte donation, the elective transfer of 2 embryos resulted in similar pregnancy rates and significantly reduced multiple gestation rates when compared to the elective transfer of 3 embryos.