Facteurs cliniques et résultats du don d'ovocytes

Endometriosis and IVF treatment outcomes: unpacking the process

Advanced endometriosis is associated with a reduction of IVF success. Surgical damage to the ovarian reserve following the excision of endometriomas has been claimed as a critical factor in the explanation of this detrimental effect. However, it is generally inferred that other mechanisms might also hamper IVF success in affected women. They include diminished responsiveness to ovarian stimulation, altered steroidogenesis, a decline in oocyte quality, reduced fertilization and embryo development, and impaired implantation. To navigate these limitations, we scrutinized available literature for studies specifically designed to address distinct phases of the IVF process. Utmost consideration was given to intra-patient ovarian response comparisons in women with unilateral endometriomas and to studies applying a meticulous matching to control confounders. The following observations have been drawn: 1) endometriosis has a negligible impact on ovarian response. A slight reduction in stimulation response can only be observed for endometriomas larger than 4 cm. Follicular steroidogenesis is unaffected; 2) oocyte quality is not hampered. Fertilization rates are similar, and intracytoplasmic sperm injection (ICSI) is not justified. Embryonic development is uncompromised, with no increase in aneuploidy rate; 3) endometrial receptivity is either unaffected or only slightly impacted. In conclusion, our study suggests that, aside from the well-known negative effect on ovarian reserve from excisional endometrioma surgeries, endometriosis does not significantly affect IVF outcomes.

Differential sperm proteomic profiles according to pregnancy achievement in intracytoplasmic sperm injection cycles: a pilot study

PURPOSE

To describe the proteomic profiles in semen samples and define the differences in sperm proteomic profiles among samples that ultimately achieved pregnancy (P) via intracytoplasmic sperm injection (ICSI) in an oocyte donation program and those that were unsuccessful (NP).

METHODS

Prospective, analytical, observational nested case and control study evaluating the proteomic profile of spermatozoa from patients' ejaculates where pregnancies were (group pregnant (P), n= 4) or were not (group non-pregnant (NP), n=4) achieved after ICSI in an oocyte donation program aiming to standardize female factor. Proteins were separated and analyzed by means of SWATH-MS) and compared between P/NP groups to identify sperm biomarkers of fertility/infertility. Proteins are available via ProteomeXchange.

RESULTS

We identified and quantified 2228 proteins, with 37 significantly higher in the P group and 16 higher in NP. Enrichment analysis revealed that the increased proteins in P group sperm were related to motility, anaerobic metabolism, and protein biosynthesis functions, while the increased proteins in the NP group were involved in protein biosynthesis, protein folding, aerobic metabolism, and signal transduction, all of which are functions not previously described as influencing sperm success. Some proteins identified (e.g., SLC2A3, or CD81) are located in the cell membrane and thus may be employed to select spermatozoa by magnetic-activated cell sorting (MACS).

CONCLUSION(S)

This work revealed differences in the proteomic profiles of sperm samples successful in achieving pregnancy and those that were not, expanding our understanding of sperm function and infertility-related molecular markers, and enabling the future development of male fertility diagnostic tools and therapies.

Endometrial preparation: effect of estrogen dose and administration route on reproductive outcomes in oocyte donation cycles with fresh embryo transfer

STUDY QUESTION

Is there a difference in live birth rates following endometrial preparation with either a constant or increasing estrogen dose in fresh embryo transfer from oocyte donation cycles?

SUMMARY ANSWER

There is no difference in live birth rates between a constant dose versus an increasing dose of estrogen after fresh embryo transfer in oocyte donation cycles with oral or transdermal supplementation.

WHAT IS KNOWN ALREADY

Endometrial preparation (EP) with estrogen and progesterone, and embryo-endometrial synchronicity are determinant for adequate embryo implantation. Estrogen is crucial and different exogenous administration patterns could imply variations on EP. Moreover, estrogen undergoes metabolization by the intestines and liver when administered orally, an effect that is bypassed by transdermal administration. Information on the effect of replacement patterns and route of administration of E on reproductive outcomes of women undergoing fresh embryo transfer from oocyte donation cycles is scarce.

STUDY DESIGN, SIZE, DURATION

Retrospective cohort study including 8362 embryo transfers following ICSI, corresponding to 8254 patients, between October 2010 and March 2015. A total of 5593 (66.9%) patients received an increasing E dose (ID) (oral: 2 mg/day day(d)1-7, 4 mg days d8-12, 6 mg d13-embryo transfer; transdermal: 75 µg/3 days on d1-6, 150 µg/3 days d7-embryo transfer) while 2769 (33.1%) received a constant dose (CD) of estrogen (oral: 6 mg/day 1-embryo transfer; transdermal: 150 µg/3 days d1-embryo transfer). Embryos were generated by ICSI with fresh or vitrified donor oocytes fertilized with either fresh or frozen sperm from either the couple partner or donor.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Cohort allocation was not related to patient characteristics; instead it reflected an internal policy change in E administration. Effect of estrogen dose (ID versus CD) on biochemical, clinical, ongoing and live birth rates, stratified by administration route, was analyzed by univariate and multivariate analysis adjusted by donor and recipient demographic and cycle characteristics.

MAIN RESULTS AND THE ROLE OF CHANCE

No difference in live birth rate was found between CD and ID for oral (33.0 versus 32.5%, P = 0.81) and transdermal (35.3 versus 33.5%, P = 0.33) supplementation. Biochemical pregnancy rate was higher in CD than ID (53.7 versus 47.5%, P < 0.001) when patients received oral supplementation. Adjusted analysis confirmed that oral administration had a greater impact on biochemical pregnancy rates than transdermal (odds ratio (OR) 1.28; 95% confidence interval (CI) 1.11-1.48, P = 0.001 versus OR 1.13; 95% CI 1.00-1.30, P = 0.055). Sub-analysis of transfers between day 12 and 15 of estrogen supplementation showed no difference between CD and ID in pregnancy outcomes. Demographic variables and cycle characteristics were comparable between both groups. Moreover, the use of the oocyte donation model reduces confounding factors related to oocyte age, embryo aneuploidy, and embryo quality.

LIMITATIONS, REASONS FOR CAUTION

The greatest limitation of this study is its retrospective nature. On the other hand, this study was performed using donated oocytes; although this is unlikely to affect the results, we cannot exclude the possibility that a high quality female gamete responds differently to endometrial state in comparison to a patient's own oocytes.

WIDER IMPLICATIONS OF THE FINDINGS

In fresh embryo transfer from oocyte donation cycles, changes in the protocol of E replacement do not seem to have an impact on clinical outcomes and performance; for this reason estrogen replacement protocols can be adjusted to the patient's characteristics and preferences as well as to the most cost effective strategy.

STUDY FUNDING/COMPETING INTERESTS

None.

[An update on adenomyosis and implantation]

Adenomyosis is an enigmatic disease whose impact on implantation and fertility outcome is still controversial. A negative effect on IVF outcome was already observed, but it is mainly explained by an increase in early spontaneous miscarriages. We reviewed scientific data in order to bring relevant information about adenomyosis and endometrial receptivity for patient counselling and to precise if screening of adenomyosis is indicated before IVF treatment.

Association between endometrial thickness in oocyte donation cycles and pregnancy success rates

Endometrial receptivity is a primary concern for embryo implantation success in fertility treatments. The present study was a retrospective analysis of 4070 cycles with donor oocytes and hormone-replacement therapy. Endometrial thickness was assessed once with transvaginal ultrasound. Patients were allowed to continue when endometrial thickness was ?5mm and had triple line morphology. Pregnancy rates, the number of gestational sacs and miscarriage rates were analysed in relation to endometrium status. Regression models were used to analyse associations, taking the day of embryo transfer into account. All patient parameters were homogeneous. Mean endometrial thickness was 7.24±1.66mm, the mean number of embryos transferred was 2.04±0.43, the pregnancy rate was 48.06% and sacs were present in 42.3% of cycles. There were no significant differences in pregnancy rates, number of gestational sacs and miscarriage rates for different endometrial thickness measurements. The present study is, to our knowledge, the largest study evaluating the role of endometrial thickness in oocyte donation cycles. Endometrial thickness >5mm is a reasonable parameter for determining treatment success, and once it is observed in a single ultrasonographic evaluation there is no need for subsequent monitoring and embryo transfer can be scheduled over the following 1-16 days, because the results are not compromised. This may lead to a significant reduction in time and cost in fertility clinics.

Management of infertility in women over 40

Women's fertility potential is declining with age because of multiples intrinsic and extrinsic factors such as life style, oxidative stress and/or endocrine disruptors and is affecting the ability of these women to conceive naturally. This declining fertility potential and the late age of motherhood is increasing significantly the number of patients consulting infertility specialists. Different strategies of investigation and management are proposed to patients over 40 in order to overcome their infertility and improve the live birth rate in these patients. Intra Uterine Insemination (IUI) in women over 40 is associated with a low rate of ongoing pregnancy and IUI should not therefore be offered always as the first line of treatment. When the predictive factors are positive IVF/ICSI seem to be good alternatives until 43 years of age. Customized ovarian stimulation and flexible laboratory methods such as in vitro maturation (IVM), preimplantation genetic diagnosis (PGD), embryo vitrification and transfer after thawing in subsequent natural or artificial cycles can improve the success rate of ART in patients over 40. Meanwhile, oocyte and embryos donation remain good options for patient over 40 with a bad prognosis and can lead to successful ongoing pregnancies until 45 years of age. Ovarian tissue cryopreservation, oocyte vitrification at the germinal vesicle (GV) stage or metaphase II stage present a breakthrough for fertility preservation but the ideal age for starting fertility preservation is still debated as well as the minimum number of oocytes to be vitrified in order to optimize the chances of pregnancy when needed at an older age. This manuscript reports the results of our own experience from patients older than 40 in the light of the published data and discusses the different therapeutic alternatives which can be proposed to patients over 40 consulting ART centres.