Do BRCA1/2 mutation carriers have an earlier onset of natural menopause?

Conditional loss of Brca1 in oocytes causes reduced litter size, ovarian reserve depletion and impaired oocyte in vitro maturation with advanced reproductive age in mice

BACKGROUND

An estimated 1 in 350 women carry germline BRCA1/2 mutations, which confer an increased risk of developing breast and ovarian cancer, and may also contribute to subfertility. All mature, sex steroid-producing ovarian follicles are drawn from the pool of non-renewable primordial follicles, termed the 'ovarian reserve'. The clinical implications of early ovarian reserve exhaustion extend beyond infertility, to include the long-term adverse health consequences of loss of endocrine function and premature menopause. We aimed to determine whether conditional loss of Brca1 in oocytes impacts ovarian follicle numbers, oocyte quality and fertility in mice with advancing maternal age. We also aimed to determine the utility of AMH as a marker of ovarian function, by assessing circulating AMH levels in mice and women with BRCA1/2 mutations, and correlating this with ovarian follicle counts.

METHODS

In this study, we addressed a longstanding question in the field regarding the functional consequences of BRCA1 inactivation in oocytes. To recapitulate loss of BRCA1 protein function in oocytes, we generated mice with conditional gene deletion of Brca1 in oocytes using Gdf9-Cre recombinase (WT: Brca1fl/flGdf9+/+; cKO: Brca1fl/flGdf9cre/+).

FINDINGS

While the length of the fertile lifespan was not altered between groups after a comprehensive breeding trial, conditional loss of Brca1 in oocytes led to reduced litter size in female mice. Brca1 cKO animals had a reduced ovarian reserve and oocyte maturation was impaired with advanced maternal age at postnatal day (PN)300, compared to WT animals. Serum anti-Müllerian hormone (AMH) concentrations (the gold-standard indirect marker of the ovarian reserve used in clinical practice) were not predictive of reduced primordial follicle number in Brca1 cKO mice versus WT. Furthermore, we found no correlation between follicle number or density and serum AMH concentrations in matched samples from a small cohort of premenopausal women with BRCA1/2 mutations.

INTERPRETATION

Together, our data demonstrate that BRCA1 is a key regulator of oocyte number and quality in females and suggest that caution should be used in relying on AMH as a reliable marker of the ovarian reserve in this context.

FUNDING

This work was made possible through Victorian State Government Operational Infrastructure Support and Australian Government NHMRC IRIISS. This work was supported by funding from the Australian Research Council (ALW - DE21010037 and KJH - FT190100265), as well as the National Breast Cancer Foundation (IIRS-22-092) awarded to ALW and KJH. LRA, YML, LT, EOKS and MG were supported by Australian Government Research Training Program Scholarships. LRA, YML and LT were also supported by a Monash Graduate Excellence Scholarship. YC, SG and XC were supported by Monash Biomedicine Discovery Institute PhD Scholarships. LRA was also supported by a Monash University ECPF24-6809920940 Fellowship. JMS was supported by NHMRC funding (2011299). MH was supported by an NHMRC Investigator Grant (1193838).

BRCA Mutations and Fertility Preservation

Hereditary cancers mostly affect the adolescent and young adult population (AYA) at reproductive age. Mutations in BReast CAncer (BRCA) genes are responsible for the majority of cases of hereditary breast and ovarian cancer. BRCA1 and BRCA2 act as tumor suppressor genes as they are key regulators of DNA repair through homologous recombination. Evidence of the accumulation of DNA double-strand break has been reported in aging oocytes, while BRCA expression decreases, leading to the hypothesis that BRCA mutation may impact fertility. Moreover, patients exposed to anticancer treatments are at higher risk of fertility-related issues, and BRCA mutations could exacerbate the treatment-induced depletion of the ovarian reserve. In this review, we summarized the functions of both genes and reported the current knowledge on the impact of BRCA mutations on ovarian ageing, premature ovarian insufficiency, female fertility preservation strategies and insights about male infertility. Altogether, this review provides relevant up-to-date information on the impact of BRCA1/2 mutations on fertility. Notably, BRCA-mutated patients should be adequately counselled for fertility preservation strategies, considering their higher sensitivity to chemotherapy gonadotoxic effects.

Approaches to Fertility Preservation for Young Women With Breast Cancer

In patients with early breast cancer, the combination of different systemic treatment strategies, including chemotherapy, endocrine therapy, targeted therapy, and more recently also immunotherapy has demonstrated to significantly improve their survival outcomes. However, this gain is often obtained at the cost of higher toxicity calling for the need of increased attention toward survivorship-related issues, including fertility preservation in young women. According to available guidelines, health care providers should offer oncofertility counseling to all patients with cancer diagnosed at reproductive age. Counselling should focus on the risk of gonadotoxicity of anticancer treatments and on the access to fertility preservation techniques. However, several surveys have demonstrated suboptimal implementation of these recommendations. This review aims at summarizing the available evidence on oncofertility to guide health care providers involved in the management of young women with breast cancer. Available and effective options for fertility preservation include oocyte/embryo cryopreservation or ovarian tissue cryopreservation. Patient, disease, and treatment characteristics should be carefully considered when offering these strategies. Ovarian function preservation with gonadotrophin-releasing hormone agonists during chemotherapy should be discussed and offered to every premenopausal woman concerned about developing premature ovarian insufficiency and independently of her wish to preserve fertility. Current available data confirm that pregnancy occurring after proper treatment for breast cancer is safe, both in terms of long-term clinical outcomes and for the babies. Fertility preservation and pregnancy desire should be pivotal components of the multimodal management of breast cancer in young women, and require a multidisciplinary approach based on close collaborations between oncologists and fertility specialists.

VTT, J.C. EM, G.W.M. LE, Irene H, Mariette G, J.T. VGR, Willem V, D. LK, J.M. BF, M.E. BA. The Impact of BRCA1- and BRCA2 Mutations on Ovarian Reserve Status

This study aimed to investigate whether female BRCA1- and BRCA2 mutation carriers have a reduced ovarian reserve status, based on serum anti-Mullerian hormone (AMH) levels, antral follicle count (AFC) and ovarian response to ovarian hyperstimulation. A prospective, multinational cohort study was performed between October 2014 and December 2019. Normo-ovulatory women, aged 18-41 years old, applying for their first PGT-cycle for reason of a BRCA mutation (cases) or other genetic diseases unrelated to ovarian reserve (controls), were asked to participate. All participants underwent a ICSI-PGT cycle with a long-agonist protocol for controlled ovarian hyperstimulation. Linear and logistic regression models were used to compare AMH, AFC and ovarian response in cases and controls. Sensitivity analyses were conducted on BRCA1- and BRCA2 mutation carrier subgroups. Thirty-six BRCA mutation carriers (18 BRCA1- and 18 BRCA2 mutation carriers) and 126 controls, with mean female age 30.4 years, were included in the primary analysis. Unadjusted median AMH serum levels (IQR) were 2.40 (1.80-3.00) ng/ml in BRCA mutation carriers and 2.15 (1.30-3.40) ng/ml in controls (p = 0.45), median AFC (IQR) was 15.0 (10.8-20.3) and 14.5 (9.0-20.0), p = 0.54, respectively. Low response rate was 22.6% among BRCA mutation carriers and 9.3% among controls, p = 0.06. Median number of retrieved oocytes was 9 (6-14) in carriers and 10 (7-13) in controls, p = 0.36. No substantial differences were observed between BRCA1- and BRCA2 mutation carriers. Based on several biomarkers, no meaningful differences in ovarian reserve status were observed in female BRCA mutation carriers compared to controls in the context of ICSI-PGT treatment.

Reproductive issues in carriers of germline pathogenic variants in the BRCA1/2 genes: an expert meeting

BACKGROUND

Healthy individuals and patients with cancer who are carriers of germline pathogenic variants in the BRCA1/2 genes face multiple reproductive challenges that require appropriate counseling and specific expertise.

MAIN BODY

On December 5th-7th, 2019, patient advocates and physicians with expertise in the field of reproductive medicine, fertility preservation, and oncology were invited to "San Giuseppe Moscati" Hospital in Avellino (Italy) for a workshop on reproductive management of women with germline pathogenic variants in the BRCA1/2 genes. From the discussion regarding the current evidence and future prospective in the field, eight main research questions were formulated and eight recommendations were developed regarding fertility, fertility preservation, preimplantation genetic testing, and pregnancy in healthy carriers and patients with cancer.

CONCLUSION

Several misconceptions about the topic persist among health care providers and patients often resulting in a discontinuous and suboptimal management. With the aim to offer patient-tailored counseling about reproductive issues, both awareness of current evidences and research should be promoted.

Controversies in Hereditary Cancer Management

Personalized management of patients at risk ideally should involve a multidisciplinary team of not only genetic counselors and surgeons, but also women's health or menopause specialists, knowledgeable psychologists, and primary care providers or obstetrician-gynecologists aware of the risks and fears "previvors" (survivors of a predisposition to cancer who have not had the disease) face as well as the issues that are common postoperatively. Identification of patients at risk for hereditary cancer, understanding of current genetic testing modalities and potential results, knowledge about screening and prevention including timing of surveillance, preventive medication and risk-reducing surgeries, understanding limitations and comorbidities associated with these risk management strategies and long-term psychological support are all important in hereditary cancer management. We describe issues surrounding the identification of the high-risk patient, universal testing in breast and ovarian cancer, and testing in special populations. We describe a simplified approach to understanding and communicating genetic testing results and nuances of testing including direct-to-consumer testing. We highlight concerns surrounding breast cancer screening during pregnancy and lactation. A framework for practical management and counseling of women who opt for risk-reducing salpingo-oophorectomy or risk-reducing mastectomy or both is provided. We provide an in-depth discussion of questions that arise in relation to timing of surgery, fertility preservation, management of menopausal symptoms, and surgical technique. Alternative choices in women who choose to delay bilateral salpingo-oophorectomy are reviewed. Finally, the psychosocial effects of carrying a genetic mutation and the issues that women face when undergoing to risk-reducing surgery including adjustment, sexuality issues, and cosmesis are addressed.

Anti-müllerian hormone levels and antral follicle count in women with a BRCA1 or BRCA2 germline pathogenic variant: A retrospective cohort study

Background

Some studies suggested a decreased ovarian reserve among BRCA1/2 pathogenic variant carriers, with conflicting results.

Methods

We conducted a retrospective single-center observational study of ovarian reserve and spontaneous fertility comparing BRCA1/2 pathogenic variant carriers to controls (women who attended consultations to discuss fertility preservation before gonadotoxic treatment). Measures of associations between plasma AMH concentration, AFC and BRCA1/2 status were modelled by nonlinear generalized additive regression models and logistic regressions adjusted for age at plasma storage, oral contraceptive use, body mass index, cigarette smoking, and the AMH assay technique.

Results

The whole population comprised 119 BRCA1/2 pathogenic variant carriers and 92 controls. A total of 110 women (42 carriers, among whom 30 were cancer-free, and 68 controls) underwent an ovarian reserve evaluation. Spontaneous fertility analysis included all women who previously attempted to become pregnant (134 women).

We observed a tendency towards a premature decrease in ovarian reserve in BRCA1/2 pathogenic variant carriers, but no difference in mean AMH or AFC levels was found between BRCA1/2 pathogenic variant carriers and controls. An analysis of the extreme levels of AMH (≤5 pmol/l) and AFC (≤7 follicles) by logistic regression suggested a higher risk of low ovarian reserve among BRCA1/2 pathogenic variant carriers (adjusted odds ratio (OR) = 3.57, 95% CI = 1.00–12.8, p = 0.05; and adjusted OR = 4.99, 95% CI = 1.10–22.62, p = 0.04, respectively).

Discussion

Attention should be paid to BRCA1/2 pathogenic variant carriers’ ovarian reserve, considering this potential risk of premature alteration.

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A tendency towards a premature decrease in the ovarian reserve in BRCA1/2 pathogenic variant carriers was found.

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BRCA1/2 pathogenic variant carriers presented a higher risk of a low ovarian reserve.

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Information and education regarding reproduction is mandatory among BRCA1/2 pathogenic variant carriers.

Association of Germline BRCA Pathogenic Variants With Diminished Ovarian Reserve: A Meta-Analysis of Individual Patient-Level Data

PURPOSE

To determine whether germline BRCA (gBRCA) pathogenic variants are associated with decreased ovarian reserve.

MATERIALS AND METHODS

An individual patient-level data meta-analysis was performed using five data sets on 828 evaluable women who were tested for gBRCA. Of those, 250 carried gBRCA, whereas 578 had tested negative and served as controls. Of the women with gBRCA, four centers studied those affected with breast cancer (n = 161) and one studied unaffected individuals (n = 89). The data were adjusted for the center, age, body mass index, smoking, and oral contraceptive pill use before the final analysis. Anti-Müllerian hormone (AMH) levels in affected women were drawn before presystemic therapy.

RESULTS

The mean age of women with versus without gBRCA1/2 (34.1 ± 4.9 v 34.3 ± 4.8 years; P = .48) and with gBRCA1 versus gBRCA2 (33.7 ± 4.9 v 34.6 ± 4.8 years; P = .16) was similar. After the adjustments, women with gBRCA1/2 had significantly lower AMH levels compared with controls (23% lower; 95% CI, 4 to 38; P = .02). When the adjusted analysis was limited to affected women (157 with gBRCA v 524 without, after exclusions), the difference persisted (25% lower; 95% CI, 9 to 38; P = .003). The serum AMH levels were lower in women with gBRCA1 (33% lower; 95% CI, 12 to 49; P = .004) but not gBRCA2 compared with controls (7% lower; 95% CI, 31% lower to 26% higher; P = .64).

CONCLUSION

Young women with gBRCA pathogenic variants, particularly those affected and with gBRCA1, have lower serum AMH levels compared with controls. They may need to be preferentially counseled about the possibility of shortened reproductive lifespan because of diminished ovarian reserve.

BRCA 1, 2 mutation and earlier menopause. Could BRCA 1, 2 be used as predictor of menopause?

Many studies have shown that BRCA mutation is not only related to cancer but also to ovarian aging. Studies in both human and mice oocytes have shown that Double-strand breaks (DSBs) accumulate with age. Genome-wide association studies (GWAS) have found 44 genetic loci that are related to variations when a female is about to have menopause. BRCA1 is involved in these 44 loci that are associated with the age of menopause. This review has gathered all results of literature search about the association between BRCA genes and early menopause. The majority of the articles found that women with BRCA mutation have earlier menopause compared to non-carriers. In conclusion, in the near future BRCA1,2 genes could be used as predictive biomarkers of menopause.

Age of natural menopause onset in BRCA1/2 carriers - systematic review and meta-analysis

Introduction

Germinal pathogenic variants in BRCA1 and BRCA2 genes are associated with high risk of cancers, including breast, ovary, fallopian tubes and primary peritoneal. Non-oncological implications of germline pathogenic variants in BRCA1 and BRCA2 genes, complicating reproductive health are less described. The influence of BRCA1 and BRCA2 on age of natural menopause remains inconclusive and controversial.

Material and methods

PubMed database was searched for potentially relevant abstracts. Studies which were not case-control, cohort or cross-sectional studies were subsequently excluded. Reference lists from systematic reviews or meta-analyses, dealing with the topic of menopause and BRCA1 and BRCA2 germinal pathogenic variants, were also checked to identify eligible studies. We also included our original, unpublished data from families, affected by BRCA1 or BRCA2 pathogenic variant, consisted of at least two postmenopausal female siblings with differing variant status.

Results and conclusions

Initial database search retrieved 193 abstracts. We identified 4 eligible studies for meta-analysis. Two studies not reporting dispersion measures and not reporting age of natural menopause in control group were left in summary for illustrational purposes, yet were excluded from meta-analysis. 4 studies and our original, unpublished data, combining data from 1535 germinal BRCA1 and BRCA2 pathogenic variant carriers and 3191 control individuals, did not support the hypothesis of association between germinal pathogenic variants of “breast cancer genes” and premature menopause.

BRCA-related ATM-mediated DNA double-strand break repair and ovarian aging

BACKGROUND

Oocyte aging has significant clinical consequences, and yet no treatment exists to address the age-related decline in oocyte quality. The lack of progress in the treatment of oocyte aging is due to the fact that the underlying molecular mechanisms are not sufficiently understood. BRCA1 and 2 are involved in homologous DNA recombination and play essential roles in ataxia telangiectasia mutated (ATM)-mediated DNA double-strand break (DSB) repair. A growing body of laboratory, translational and clinical evidence has emerged within the past decade indicating a role for BRCA function and ATM-mediated DNA DSB repair in ovarian aging.

OBJECTIVE AND RATIONALE

Although there are several competing or complementary theories, given the growing evidence tying BRCA function and ATM-mediated DNA DSB repair mechanisms in general to ovarian aging, we performed this review encompassing basic, translational and clinical work to assess the current state of knowledge on the topic. A clear understanding of the mechanisms underlying oocyte aging may result in targeted treatments to preserve ovarian reserve and improve oocyte quality.

SEARCH METHODS

We searched for published articles in the PubMed database containing key words, BRCA, BRCA1, BRCA2, Mutations, Fertility, Ovarian Reserve, Infertility, Mechanisms of Ovarian Aging, Oocyte or Oocyte DNA Repair, in the English-language literature until May 2019. We did not include abstracts or conference proceedings, with the exception of our own.

OUTCOMES

Laboratory studies provided robust and reproducible evidence that BRCA1 function and ATM-mediated DNA DSB repair, in general, weakens with age in oocytes of multiple species including human. In both women with BRCA mutations and BRCA-mutant mice, primordial follicle numbers are reduced and there is accelerated accumulation of DNA DSBs in oocytes. In general, women with BRCA1 mutations have lower ovarian reserves and experience earlier menopause. Laboratory evidence also supports critical role for BRCA1 and other ATM-mediated DNA DSB repair pathway members in meiotic function. When laboratory, translational and clinical evidence is considered together, BRCA-related ATM-mediated DNA DSB repair function emerges as a likely regulator of ovarian aging. Moreover, DNA damage and repair appear to be key features in chemotherapy-induced ovarian aging.

WIDER IMPLICATIONS

The existing data suggest that the BRCA-related ATM-mediated DNA repair pathway is a strong candidate to be a regulator of oocyte aging, and the age-related decline of this pathway likely impairs oocyte health. This knowledge may create an opportunity to develop targeted treatments to reverse or prevent physiological or chemotherapy-induced oocyte aging. On the immediate practical side, women with BRCA or similar mutations may need to be specially counselled for fertility preservation.

Effects of BRCA gene mutation on female reproductive potential: A systematic review

Mutation of BRCA genes significantly increases the lifetime risk of breast, ovarian, fallopian tube and primary peritoneal cancers. In addition to the increased risk of these multiple malignancies, the recent literature suggests that mutations in BRCA genes may lead to decreased reproductive potential. In this systematic review, we focus on the effect of BRCA gene mutation on reproductive potential. The main outcomes included the rate of nulliparity, ovarian reserve, ovarian response, and the age at natural menopause. A total of 23 observational studies were included for quality analysis. The certainty of evidence was low to moderate: the main limitations were imprecision and statistically significant heterogeneity. Meta-analysis suggested that the rate of nulliparity, serum anti-müllerian hormone levels, antral follicle counts and ovarian response were not significantly affected in BRCA gene mutation carriers (P > 0.05). BRCA gene mutation carriers tended to have a lower number of primordial follicles (P = 0.0002) and lower age at natural menopause than non-carriers. In conclusion, there is no compelling evidence indicating that the rate of nulliparity, serum AMH, antral follicle counts and ovarian response are affected in BRCA mutation carriers.

Risk-reducing salpingo-oophorectomy, natural menopause, and breast cancer risk: an international prospective cohort of BRCA1 and BRCA2 mutation carriers

BACKGROUND

The effect of risk-reducing salpingo-oophorectomy (RRSO) on breast cancer risk for BRCA1 and BRCA2 mutation carriers is uncertain. Retrospective analyses have suggested a protective effect but may be substantially biased. Prospective studies have had limited power, particularly for BRCA2 mutation carriers. Further, previous studies have not considered the effect of RRSO in the context of natural menopause.

METHODS

A multi-centre prospective cohort of 2272 BRCA1 and 1605 BRCA2 mutation carriers was followed for a mean of 5.4 and 4.9 years, respectively; 426 women developed incident breast cancer. RRSO was modelled as a time-dependent covariate in Cox regression, and its effect assessed in premenopausal and postmenopausal women.

RESULTS

There was no association between RRSO and breast cancer for BRCA1 (HR = 1.23; 95% CI 0.94-1.61) or BRCA2 (HR = 0.88; 95% CI 0.62-1.24) mutation carriers. For BRCA2 mutation carriers, HRs were 0.68 (95% CI 0.40-1.15) and 1.07 (95% CI 0.69-1.64) for RRSO carried out before or after age 45 years, respectively. The HR for BRCA2 mutation carriers decreased with increasing time since RRSO (HR = 0.51; 95% CI 0.26-0.99 for 5 years or longer after RRSO). Estimates for premenopausal women were similar.

CONCLUSION

We found no evidence that RRSO reduces breast cancer risk for BRCA1 mutation carriers. A potentially beneficial effect for BRCA2 mutation carriers was observed, particularly after 5 years following RRSO. These results may inform counselling and management of carriers with respect to RRSO.

Do BRCA1 and BRCA2 gene mutation carriers have a reduced ovarian reserve? Protocol for a prospective observational study

INTRODUCTION

BRCA1/2 gene mutations increase risk of breast and/or ovarian cancer and may have implications for reproductive health. Indirect biomarkers of the ovarian primordial follicle pool (anti-Müllerian hormone (AMH)) and one small study in female cadavers suggest that ovarian reserve may be reduced in BRCA mutation carriers, but findings are conflicting and association between circulating AMH and primordial follicle number is not established. The aim of this study is to measure primordial follicle density in premenopausal ovarian tissue samples from women with BRCA1/2 gene mutations versus age-matched comparison group.

METHODS AND ANALYSIS

Prospective observational study measuring associations between BRCA gene mutation status, premenopausal ovarian primordial follicle density and serum AMH concentrations versus age-matched premenopausal women from the general population. Primordial follicle density will be measured in cortical sections from ovarian tissue collected at the time of risk-reducing bilateral salpingo-oophorectomy (RRBSO) in 88 BRCA1 gene mutation carriers, 65 BRCA2 gene mutation carriers and 157 non-mutation carriers. Primordial follicle density will be determined by counting follicles in a known volume of ovarian cortical tissue using light microscopy. Follicles will be identified by immunohistochemical staining for oocyte marker mouse vasa homologue. To inform the mechanisms underlying reduced ovarian reserve, the proportion of follicles containing oocytes with DNA damage will be determined by immunohistochemical staining for phosphorylated histone H2AX and terminal deoxynucleotidyl transferase dUTP nick end labelling assay to identify apoptotic cells. Follicle density will be correlated with circulating AMH concentrations quantified in the same cohort, using an electrochemiluminescence immunoassay on an automated platform.

ETHICS AND DISSEMINATION

Ethics approval has been granted by Peter MacCallum Cancer Centre to access biobanks, including; The Kathleen Cuningham Foundation Consortium for Research into Familial Breast Cancer (kConFab-HREC#97_27) and the What Happens after Menopause? (HREC12PMCC24-12/90) and Melbourne IVF.

Issues with Fertility in Young Women with Breast Cancer

PURPOSE OF REVIEW

There are competing risks and benefits of cancer therapies and fertility preservation in young women with breast cancer. Here we discuss the impact of therapy on fertility, fertility preservation options, and emerging information in fertility issues for the breast cancer patient.

RECENT FINDINGS

All systemic forms of breast cancer treatment can impact future fertility. Pre-therapy fertility preservation may offer the best opportunity for future fertility. Shared decision making with the individual patient and clinical scenario is important. Early referral to a fertility specialist should be offered to young patients. We find that fertility preservation options for young women diagnosed with breast cancer are currently available, but potentially under-utilized. We conclude that a multidisciplinary approach is necessary, with discussion of potential risks and benefits of fertility preservation options in the context of the patient's clinical disease.

BRCA1 mutation carriers have a lower number of mature oocytes after ovarian stimulation for IVF/PGD

Purpose

The aim of this study was to determine whether BRCA1/2 mutation carriers produce fewer mature oocytes after ovarian stimulation for in vitro fertilization (IVF) with preimplantation genetic diagnosis (PGD), in comparison to a PGD control group.

Methods

A retrospective, international, multicenter cohort study was performed on data of first PGD cycles performed between January 2006 and September 2015. Data were extracted from medical files. The study was performed in one PGD center and three affiliated IVF centers in the Netherlands and one PGD center in Belgium. Exposed couples underwent PGD because of a pathogenic BRCA1/2 mutation, controls for other monogenic conditions. Only couples treated in a long gonadotropin-releasing hormone (GnRH) agonist-suppressive protocol, stimulated with at least 150 IU follicle stimulating hormone (FSH), were included. Women suspected to have a diminished ovarian reserve status due to chemotherapy, auto-immune disorders, or genetic conditions (other than BRCA1/2 mutations) were excluded. A total of 106 BRCA1/2 mutation carriers underwent PGD in this period, of which 43 (20 BRCA1 and 23 BRCA2 mutation carriers) met the inclusion criteria. They were compared to 174 controls selected by frequency matching.

Results

Thirty-eight BRCA1/2 mutation carriers (18 BRCA1 and 20 BRCA2 mutation carriers) and 154 controls proceeded to oocyte pickup. The median number of mature oocytes was 7.0 (interquartile range (IQR) 4.0–9.0) in the BRCA group as a whole, 6.5 (IQR 4.0–8.0) in BRCA1 mutation carriers, 7.5 (IQR 5.5–9.0) in BRCA2 mutation carriers, and 8.0 (IQR 6.0–11.0) in controls. Multiple linear regression analysis with the number of mature oocytes as a dependent variable and adjustment for treatment center, female age, female body mass index (BMI), type of gonadotropin used, and the total dose of gonadotropins administered revealed a significantly lower yield of mature oocytes in the BRCA group as compared to controls (p = 0.04). This finding could be fully accounted for by the BRCA1 subgroup (BRCA1 mutation carriers versus controls p = 0.02, BRCA2 mutation carriers versus controls p = 0.50).

Conclusions

Ovarian response to stimulation, expressed as the number of mature oocytes, was reduced in BRCA1 but not in BRCA2 mutation carriers. Although oocyte yield was in correspondence to a normal response in all subgroups, this finding points to a possible negative influence of the BRCA1 gene on ovarian reserve.

Electronic supplementary material

The online version of this article (doi:10.1007/s10815-017-1014-3) contains supplementary material, which is available to authorized users.