P–595 Systematic dydrogesterone supplementation of artificial endometrial preparation cycles for frozen-thawed embryo transfer during Covid–19 pandemic: a good way to limit monitoring visits and optimize outcomes

Study question

Does systematic dydrogesterone supplementation in artificial cycles (AC) for frozen-thawed embryo transfer (FET) during Covid–19 pandemic modify outcomes compared to prior individualized supplementation adjusted on serum progesterone (P) levels ?

Summary answer

Systematic dydrogesterone supplementation in AC for FET is associated with similar outcomes compared to prior individualized supplementation in patients with low P levels.

What is known already

In AC for FET using vaginal P for endometrial preparation, low serum P levels following P administration have been associated with decreased pregnancy and live birth rates. This deleterious effect can be overcome by addition of other routes of P administration. We obtained effective results by adding dydrogesterone to vaginal P and postponing FET by one day in patients with low P levels. However, in order to limit patient monitoring visits and to schedule better FET activity during Covid–19 pandemic, we implemented a systematic dydrogesterone supplementation without luteal P measurement in artificial FET cycles.

Study design, size, duration

This retrospective study aimed to analyse outcomes of 394 FET after 2 different protocols of artificial endometrial preparation. From September 2019 to Covid–19 lockdown on 15th March 2020, patients had serum P level measured on D1 of vaginal P administration. When P levels were < 11 ng/ml, dydrogesterone supplementation was administered and FET was postponed by one day. From May to December 2020, no P measurement was performed and dydrogesterone supplementation was systematically used.

Participants/materials, setting, methods

In our university hospital, endometrial preparation was performed using sequential administration of vaginal estradiol until endometrial thickness reached >7 mm, followed by transdermal estradiol combined with 800 mg/day vaginal micronized P started in the evening (D0). Oral dydrogesterone supplementation (30 mg/day) was started concomitantly to vaginal P in all patients during Covid–19 pandemic and only after D1 P measurement followed by one day FET postponement in patients with P levels <11 ng/ml before the lockdown.

Main results and the role of chance

During the Covid–19 pandemic, 198 FET were performed on D2, D3 or D5 of P administration with dydrogesterone supplementation depending on embryo stage at cryopreservation. Concerning the 196 FET before lockdown, 124 (63%) were performed after dydrogesterone addition from D1 onwards and postponement by one day in patients with serum P levels <11 ng/ml at D1 while 72 were performed in phase following introduction of vaginal P without dydrogesterone supplementation in patients with P > 11 ng/ml. Characteristics of patients in the 2 time periods were similar for age (34.5 + 5 vs 34.1 + 4.8 years), endometrial thickness prior to P introduction (9.9 + 2.1 vs 9.9 + 2.2 mm), number of transferred embryos (1.3 + 0.5 vs 1.4 + 0.5) , embryo transfer stage (D2/D3/blastocyst: 8/16/76% vs 3/18/79%). No significant difference was observed between both time periods [nor between “dydrogesterone addition and postponement by 1 day” and “in phase” FET before lockdown] in terms of positive pregnancy test (39.4% vs 39.3% [44% vs 30.5%]), heartbeat activity at 8 weeks (29.3% vs 28% [29% vs 26.4%]) and ongoing pregnancy rates at 12 weeks (30.7% but truncated at end of October 2020 vs 25.5% [26.6% vs 23.6%]).

Limitations, reasons for caution

Full results of the Covid–19 period will be further provided concerning ongoing pregnancy rates as well as comparison of live birth rates and obstetrical and neonatal outcomes.

Wider implications of the findings: These results suggest that systematic dydrogesterone supplementation is as effective as individualized supplementation according to serum P levels following administration of vaginal P. This strategy enabled us to schedule easier FET and limit patient visits for monitoring while maintaining optimal results for FET in AC during the Covid–19 pandemic.

Trial registration number

Not applicable

P–440 Seven years’ experience using oocyte vitrification/warming from in vitro maturation or controlled ovarian hyperstimulation cycles to preserve fertility for oncologic indications

Study question

Do oocytes vitrified following in vitro maturation (IVM) or controlled ovarian hyperstimulation (COH) for oncologic fertility preservation (FP), lead to similar biological/clinical outcomes after thawing?

Summary answer

IVM is a valid option when chemotherapy is urgent or COH is contraindicated. We report the second live-birth worldwide after IVM in a cancer patient.

What is known already

FP aims at maintaining in cancer survivors, the possibility of childbearing using their own gametes. Currently, oocyte vitrification after COH remains the gold standard but IVM has recently emerged as an option for young women seeking FP, when COH is contraindicated or when cancer therapy is urgent. However, the actual competence of oocyte vitrified after IVM in cancer patients is not established. To date, only one live birth has been reported following frozen/warmed oocytes from an IVM cycle and no data is available comparing biological/clinical outcomes of warmed oocytes resulting either from IVM or COH cycles in cancer survivors.

Study design, size, duration

This retrospective cohort study from a single IVF unit aimed to analyze outcomes of all oocyte warming cycles in 38 cancer survivors having undergone oocyte vitrification for FP after COH or IVM. All of them had oocyte retrieval before administration of gonadotoxic treatment and returned after being cured for assisted reproduction treatments with their oncologist agreement, between January 2014 and December 2020.

Participants/materials, setting, methods

Thirty-eight oocytes warming cycles followed by ICSI respectively from 18 COH and 22 IVM cycles were analyzed. Survival, degeneration following ICSI, fertilization, top-quality and good-quality embryos, defined at day–2 respectively as 4 and 3–5 adequate-sized blastomeres, without multinucleation and containing &lt;20% of cytoplasmic fragments, implantation, biochemical (hCG&gt;100 UI/mL), clinical (intrauterine sac with fetal heart beat) and live birth rates were compared between IVM and COH cycles using appropriate statistical tests. Significance was set at 5%.

Main results and the role of chance

The indications for FP were breast cancer (n = 32), hematologic malignancies (n = 3), BRCA1 mutation (n = 2), borderline ovarian tumor (n = 1). The mean age and antral follicle count (AFC) at the time of FP was similar in both groups. The number of cryopreserved oocytes was significantly lower in the IVM group (5.7 ± 9.1) when compared with the COH group (11.4 ± 3.3; p = 0.009). Oocyte survival rates were similar in IVM (70 ± 24%) and COH groups (73 ± 28%). Although not significant, we reported a trend to better results in the COH group when compared with those of IVM group in terms of degeneration rate following ICSI (6 ± 10% vs. 14 ± 20%; p = 0.16), fertilization (72 ± 35% vs. 54 ± 27%; p = 0.08), day 2 top-quality (38 ± 32% vs. 21 ± 31%; p = 0.15) and good-quality embryo (46 ± 30% vs. 25 ± 30%; p = 0.06), implantation (18 ± 35% vs. 14 ± 36%; p = 0.79), biochemical (28 (5/18) vs. 14% (3/22); p = 0.26), clinical (22% (4/18) vs. 9% (2/22); p = 0.24), live birth rates (22% (4/18) vs. 5% (1/22); p = 0.06).

Limitations, reasons for caution

Caution is needed when interpreting these retrospective data obtained from a limited number of frozen-thawed cycles. Statistical power to compare IVF outcomes after COH and IVM is limited by the few women who return for oocyte reutilization.

Wider implications of the findings: The present investigation is the largest evaluating the IVM-oocyte frozen-thawed cycles in a oncologic population. It suggests that a higher oocyte yield may be necessary in IVM, since fertilization/embryo-quality rates seem lower. Success rates and limiting factors of oocyte vitrification in this context is needed for providing proper oncofertility counseling.

Trial registration number

Not applicable