Markers of ovarian reserve in young girls with Turner's syndrome

Markers of Fertility in Adolescents With Chronic Endocrinopathies at Transition From Paediatric to Adult Care

OBJECTIVE

During the process of transition from paediatric to adult health care, counselling concerning fertility is an important issue and is based mainly on serum markers of gonadal function. Here, we analysed these markers in adolescents with various underlying endocrine diseases at the time of transition.

METHODS

After reaching near adult height and late puberty (girls: bone age [BA] ≥14 years, and boys: BA ≥16 years), we assessed stages of puberty according to Tanner and measured testes or ovarian volumes and serum markers of gonadal function (anti-Mullerian hormone [AMH], inhibin B, 17β-estradiol, testosterone).

RESULTS

One hundred and ten patients (56 females and 54 males) were included from May 2010 to March 2016 with multiple pituitary hormone deficiency (MPHD; n = 17), growth hormone deficiency (GHD; n = 35), Turner syndrome (TS; n = 27), short stature after being born small for gestational age (SGA; n = 20) and Klinefelter syndrome (KS; n = 11). Female and male adolescents exhibited mature secondary sexual characteristics. The levels of serum inhibin B and AMH were lower in TS and female MPHD than in GHD and SGA, each independently (p < 0.05). The levels of serum AMH were higher whereas serum inhibin B were lower in male MPHD and KS (p < 0.05). Ovary volumes were significantly smaller in patients with TS, and testicular volumes were smaller in patients with KS.

CONCLUSIONS

After current established treatments with sex steroids, the development of secondary sexual characteristics was mature. However, impaired markers of fertility have been identified in patients with TS, KS and MPHD, reflecting gonadal dysgenesis in TS and KS, but gonadal immaturity in MPHD as gonadal gonadotropin stimulation is lacking throughout development. Consequently, in patients with MPHD, these markers cannot reliably predict individual fertility, which warrants consideration and incorporation in future treatment concepts.

Navigating fertility dilemmas across the lifespan in girls with Turner syndrome-a scoping review

BACKGROUND

Girls with Turner syndrome (TS) lack a partial or complete sex chromosome, which causes an accelerated decline of their ovarian reserve. Girls have to deal with several dilemmas related to their fertility, while only a limited number of them are referred to a fertility specialist and counselled about options of family planning on time.

OBJECTIVE AND RATIONALE

This scoping review provides an update of the literature on fertility in girls with TS throughout their lifespan and aims to propose a clinical practice guideline on fertility in TS.

SEARCH METHODS

Databases of PubMed, Embase, and Web of science were searched using the following key terms: Turner syndrome, fertility, puberty, pregnancy, sex-hormones, karyotype, fertility preservation, assisted reproductive techniques, and counselling, alongside relevant subject headings and synonymous terms. English language articles published since 2007 were critically reviewed. Pregnancies after using donated oocytes and data about girls with TS with Y-chromosomal content were excluded.

OUTCOMES

This search identified 1269 studies of which 120 were extracted for the review. The prevalence of natural conception ranged from 15% to 48% in women with 45,X/46,XX, 1% to 3% in women with 45,X, and 4% to 9% in women with other TS karyotypes. When assessing a girl's fertility potential, it was crucial to determine the karyotype in two cell lines, because hidden mosaicism may exist. In addition to karyotype, assessment of anti-Müllerian hormone (AMH) played a significant role in estimating ovarian function. Girls with AMH above the detection limit were most likely to experience spontaneous thelarche, menarche, and ongoing ovarian function during the reproductive lifespan. Fertility preservation became more routine practice: vitrification of oocytes was reported in 58 girls with TS and a median of five oocytes were preserved per stimulation. Ovarian tissue cryopreservation has demonstrated the presence of follicles in approximately 30% of girls with TS, mostly in girls with mosaic-TS, spontaneous puberty, and AMH above the detection limit. Although girls and their parents appreciated receiving counselling on fertility in TS, only one in ten girls with TS received specialized counselling. Unfamiliarity with fertility preservation techniques or uncertainties regarding the eligibility of a girl for fertility preservation constituted barriers for healthcare professionals when discussing fertility with girls with TS.

WIDER IMPLICATIONS

There currently is a high demand for fertility preservation techniques in girls with TS. A reliable prognostic model to determine which girls with TS might benefit from fertility preservation is lacking. Only a minority of these girls received comprehensive fertility counselling on the full spectrum of fertility, including uncertainties of fertility preservation, pregnancy risks, and alternatives, such as adoption. Fertility preservation could be a viable option for girls with TS. However, the question remains whether enough oocytes can be obtained for a realistic prospect of a live birth. It is important that girls and parents are empowered with the necessary information to make a well-informed decision.

Reproductive health in Turner's syndrome: from puberty to pregnancy

Turner syndrome (TS) is a genetic pathology that affects about 1/2500 newborn females. Turner's syndrome is characterized by highly variable genetic anomalies that consist in a partial or complete deletion of the X sexual chromosome; it can be present as a monosomy or as a mosaicism with two o three different cellular lines. 50% of the patients with Turner's syndrome has a 45 XO karyotype while the remaining cases have karyotypes with mosaicism or X isochromosome or with partial or whole Y chromosome. This pathology is characterized by multiple anomalies that involve physical and cognitive development and in particular endocrine, cardiovascular, reproductive, auditive and visual systems. Integrity of the X chromosome in essential for fertility. In TS is accelerated germ cells apoptosis. About 30% of TS girls have some pubertal development, 10-20% undergo menarche and 2-8% go through spontaneous pregnancy. Women with TS should be informed about the risk of premature menopause and should be referred, if possible, to a specialist evaluation with a doctor expert in assisted reproductive techniques. In adolescents and in adults, Premature Ovarian Insufficiency (POI) can be evaluated clinically and biochemically with the classic combination of amenorrhea and elevated FSH concentrations (hypergonadotropic hypogonadism). However, in postpubertal adolescents and adult women, reproductive hormones may remain within the normal range before POI is clinically evident, despite significant depletion of the ovarian reserve. Today, reproductive medicine offers the opportunity of fertility preservation in women with premature ovarian insufficiency (POI). Two techniques have been suggested such as ovarian cortex cryopreservation and oocytes cryopreservation.

Oocyte cryopreservation with in vitro maturation for fertility preservation in girls at risk for ovarian insufficiency

PURPOSE

To assess the feasibility and outcomes of oocyte cryopreservation with in vitro maturation (IVM) in post-pubertal girls undergoing fertility preservation (FP) for primary ovarian insufficiency (POI) risk.

METHODS

Ovarian stimulation was performed with an antagonist protocol or progesterone priming. Ultrasound monitoring was performed transabdominally. Oocytes were retrieved transvaginally under IV sedation. Immature oocytes were subjected to IVM for up to 36 h. All MII oocytes were vitrified. The main outcome measure was the total number of mature oocytes cryopreserved. The secondary outcome was the increase in the mature oocyte yield after IVM.

RESULTS

Indications for FP included mosaic Turner syndrome (mTS; n = 10), malignancy (n = 3), and POI risk (n = 2). The mean ± SD age, antral follicle count (AFC), and AMH levels were 14.2 ± 1.4 years, 8 ± 5.2 and 1.3 ± 1.3 ng/mL. In girls with mTS, the ovarian reserve was low for age (AFC 7.4 ± 4.7 and AMH 1.4 ± 1.6 ng/mL). Oocyte cryopreservation was possible in all girls with a range of 1-27 mature oocytes obtained, even in those who were previously exposed to chemotherapy or with low ovarian reserve, and no surgical complications were encountered. After IVM, the median mature oocyte yield increased significantly from 7.5 to 10.5 (p = 0.001).

CONCLUSIONS

Oocyte cryopreservation appears to be feasible and safe in girls as young as 12 years of age at risk for POI The utility of IVM increases the yield of cryopreserved mature oocytes. Prior exposure to chemotherapy or low ovarian reserve should not be an automatic reason to exclude these girls from FP consideration.

AMH and other markers of ovarian function in patients with Turner syndrome - a single center experience of transition from pediatric to gynecological follow up

Turner syndrome (TS) is a chromosomal disorder that affects about 1 in 2500 female births and is characterized by the partial or complete absence of the second X chromosome. Depending on karyotype, TS is associated with primary ovarian insufficiency (POI). Approximately 50% of girls with a mosaic 45, X/46, XX karyotype may enter puberty spontaneously, but only 5-10% of women with TS achieve pregnancy without egg donation. In this review, we will evaluate the clinical use of markers of ovarian function in TS patients. Based on longitudinal studies of serum concentrations of reproductive hormones as well as ovarian morphology in healthy females and patients with TS, we will evaluate how they can be applied in a clinical setting. This is important when counseling patients and their families about future ovarian function essential for pubertal development and fertility. Furthermore, we will report on 20 years of experience of transition from pediatric to gynecological and adult endocrinological care in our center at Rigshospitalet, Copenhagen, Denmark.

The Cut-Off Value of Serum Anti-Müllerian Hormone Levels for the Diagnosis of Turner Syndrome with Spontaneous Puberty

OBJECTIVE

Preservation of fertility in Turner syndrome (TS) patients may be feasible through cryopreservation of ovarian tissue before follicles begin to disappear. Anti-Müllerian hormone (AMH) is said to be a predictive factor of spontaneous pubertal development in TS. We aimed to determine the cut-off values of AMH for the diagnosis of TS girls with spontaneous puberty. Design and methods: A total of 95 TS patients between 4 and 17 years were evaluated at the Department of Pediatric Genetic Metabolism and Endocrinology from July 2017 to March 2022. Serum AMH, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) levels were analyzed according to age, karyotype, pubertal development, and ultrasound ovarian visualization. Receiver-operating characteristic (ROC) curve analyzes were used to test the utility of AMH for the diagnosis of TS girls with spontaneous puberty.

RESULTS

One-fourth of TS girls aged 8-17 years had spontaneous breast development, with the ratios as follows: 45, X (6/28, 21.4%), mosaicism (7/12, 58.3%), and mosaicism with structural X chromosome abnormalities (SCA) (2/13, 15.4%), SCA (1/13, 7.7%), and Y chromosome (1/3, 33.3%). The AMH cut-off value for the prediction of spontaneous puberty in TS patients was 0.07 ng/ml, with sensitivity and specificity both at 88%. FSH, LH levels, and Karyotypes could not be considered as markers of spontaneous puberty in TS (P > 0.05). A strong relationship was observed between serum AMH levels and spontaneous puberty or ultrasound bilateral ovarian visualization.

CONCLUSIONS

The AMH cut-off value for the prediction of spontaneous puberty in TS girls aged 8-17 years was 0.07 ng/ml, with sensitivity and specificity both at 88%. However, spontaneous puberty in these patients is not predictable based on karyotype or FSH or LH levels.

First live birth after fertility preservation using vitrification of oocytes in a woman with mosaic Turner syndrome

PURPOSE

To report the case of a young woman diagnosed with Turner syndrome (TS) who achieved a live birth using her own oocytes that had been vitrified for fertility preservation.

METHODS

A 25-year-old woman with mosaic (45,X/46,XX) TS was referred for fertility preservation (FP) counseling. Serum anti-Müllerian hormone (AMH) level was normal (6.4 µg/L). In view of the unpredictable rate of follicle loss in TS individuals, she requested FP and underwent two cycles of ovarian stimulation (OS) for oocyte cryopreservation (OoC) using a GnRH antagonist protocol and recombinant follicle stimulating hormone (rFSH), 200-250 IU daily for 8 resp. 12 days.

RESULTS

In total, 29 metaphase II oocytes (MII) were vitrified after OS. After conceiving spontaneously and achieving a live birth, she returned to the clinic five years after OoC with a desire for pregnancy using in vitro fertilization (IVF) of her cryopreserved oocytes and preimplantation genetic testing (PGT-A). All 29 MII oocytes were thawed; 23 oocytes survived (79.3%) and were inseminated with partner sperm using intracytoplasmic sperm injection (ICSI). Thirteen oocytes were fertilized resulting in three good quality blastocysts which were vitrified after trophectoderm biopsy for PGT-A using array-CGH. Two blastocysts were found to be euploid. One was thawed and transferred to the uterus using a HRT priming protocol. An uneventful pregnancy occurred. The patient delivered a healthy baby girl weighing 3490 g at 40 weeks of gestation.

CONCLUSIONS

We report the first live birth achieved using cryopreserved oocytes in a woman diagnosed with mosaic TS. Cryopreservation of oocytes after ovarian stimulation is a realistic option for FP in selected post menarche individuals with mosaic TS. Whether PGT-A may reduce the risk of pregnancy loss in TS has to be confirmed by further studies.

Progress in Fertility Preservation Strategies in Turner Syndrome

Growth retardation and gonadal dysgenesis are two of the most important clinical manifestations of Turner syndrome (TS). As premature ovarian failure generally occurs early in life in women with TS, these patients should be counseled and evaluated as early as possible for discussion of optimal and individualized fertility preservation strategies. Infertility seriously affects the quality of life of women with TS. For those who have ovarian reserve, the theoretical options for future fertility in TS patients include cryopreservation of oocytes, ovarian tissues, and embryos. For those who have already lost their ovarian reserve, oocyte or embryo donation, gestational surrogacy, and adoption are strategies that allow fulfillment of desire for parenting. This review describes the etiologies of infertility and reviews the fertility preservation strategies for women with TS.

Hypogonadism and Sex Steroid Replacement Therapy in Girls with Turner Syndrome

Turner syndrome is the most common example of hypergonadotropic hypogonadism resulting from gonadal dysgenesis. Most patients present delayed, or even absent, puberty. Premature ovarian failure can be expected even if spontaneous menarche occurs. Laboratory markers of gonadal dysgenesis are well known. The choice of optimal hormone replacement therapy in children and adolescents remains controversial, particularly regarding the age at which therapy should be initiated, and the dose and route of estrogen administration. On the basis of a review of the literature, we present the most acceptable schedule of sex steroid replacement therapy in younger patients with Turner syndrome.

Fertility Preservation in Women with Turner Syndrome: A Comprehensive Review and Practical Guidelines

In this article we review the existing fertility preservation options for women diagnosed with Turner syndrome and provide practical guidelines for the practitioner. Turner syndrome is the most common sex chromosome abnormality in women, occurring in approximately 1 in 2500 live births. Women with Turner syndrome are at extremely high risk for primary ovarian insufficiency and infertility. Although approximately 70%-80% have no spontaneous pubertal development and 90% experience primary amenorrhea, the remainder might possess a small residual of ovarian follicles at birth or early childhood. The present challenge is to identify these women as early in life as is possible, to allow them to benefit from a variety of existing fertility preservation options. To maximize the benefits of fertility preservation, all women with Turner syndrome should be evaluated by an expert as soon as possible in childhood because the vast majority will have their ovarian reserve depleted before adulthood. Cryopreservation of mature oocytes and embryos is a proven fertility preservation approach, and cryopreservation of ovarian tissue is a promising technique with a growing number of live births, but remains investigational. Oocyte cryopreservation has been performed in children with Turner syndrome as young as 13 years of age and ovarian tissue cryopreservation in affected prepubertal children. However, current efficacy of these approaches is unknown in this cohort. For those who have already lost their ovarian reserve, oocyte or embryo donation and adoption are strategies that allow fulfillment of the desire for parenting. For those with Turner syndrome-related cardiac contraindications to pregnancy, use of gestational surrogacy allows the possibility of biological parenting using their own oocytes. Alternatively, gestational surrogacy can serve to carry pregnancy resulting from the use of donor oocytes or embryos, if needed.

[Fertility preservation in women of the childbearing age: Indications and strategies]

Advances on cryopreservation techniques now allow considering oocyte, embryo or ovarian tissue freezing for female fertility preservation. Originally developed for patients suffering from cancer, fertility preservation has rapidly invaded others medical fields, and represents now the standard of care for all young patient diagnosed with a disease that could impair fertility or having to receive possibly gonadotoxic treatment. As a result, autoimmune diseases, some genetic pathologies or iterative pelvic surgeries, at risk of premature ovarian failure, have become common indications of fertility preservation. In addition, the social egg freezing aiming at preventing the age-related fertility decline is still debated in France, although authorized in numerous countries. This review will discuss the different strategies of fertility preservation in young girls and women of reproductive age, regarding different medical or non-medical indications.

Inhibin B in adolescents and young adults with Turner syndrome

OBJECTIVE

Primary gonadal failure may occur in most individuals with Turner syndrome (TS). Since ovaries in TS girls undergo premature apoptosis and cryopreservation of ovarian tissue is now feasible, it would be useful to identify a reliable marker of ovarian reserve in these patients. We planned to evaluate ovarian function in a group of TS patients by measuring both traditional markers and inhibin B and to compare these results with those of a control group.

STUDY DESIGN

We enrolled 23 patients with TS and 17 age-matched healthy girls. The median age of our TS patients was 17.6 years. Three out of the 23 patients (13%) showed spontaneous pubertal development and regular menstrual cycles; the remaining 20 (86.9%) presented with primary amenorrhea.

RESULTS

The median level of inhibin B in the TS patients with primary amenorrhea was 42 pg/mL and did not differ significantly among the different subgroups in relation to karyotype. The median inhibin B level in the control group was significantly higher than in the TS girls with primary amenorrhea (83 vs. 42 pg/mL, p<0.00001). In the three patients with TS and spontaneous menstrual cycles, the inhibin B levels were significantly higher when compared to the values of the TS girls with primary amenorrhea.

CONCLUSION

TS patients with primary amenorrhea have significantly lower levels of inhibin B than TS girls with spontaneous puberty and healthy controls. Inhibin B does not correlate with follicle-stimulating hormone/luteinizing hormone. If our results are confirmed in further studies, inhibin B could become a first-line screening test for assessing ovarian reserve and a longitudinal marker of the possible decline of ovarian function in TS.

Oocyte cryopreservation for fertility preservation in postpubertal female children at risk for premature ovarian failure due to accelerated follicle loss in Turner syndrome or cancer treatments

OBJECTIVE

To preliminarily study the feasibility of oocyte cryopreservation in postpubertal girls aged between 13 and 15 years who were at risk for premature ovarian failure due to the accelerated follicle loss associated with Turner syndrome or cancer treatments.

DESIGN

Retrospective cohort and review of literature.

SETTING

Academic fertility preservation unit.

PARTICIPANTS

Three girls diagnosed with Turner syndrome, 1 girl diagnosed with germ-cell tumor. and 1 girl diagnosed with lymphoblastic leukemia.

INTERVENTIONS

Assessment of ovarian reserve, ovarian stimulation, oocyte retrieval, in vitro maturation, and mature oocyte cryopreservation.

MAIN OUTCOME MEASURE

Response to ovarian stimulation, number of mature oocytes cryopreserved and complications, if any.

RESULTS

Mean anti-müllerian hormone, baseline follical stimulating hormone, estradiol, and antral follicle counts were 1.30 ± 0.39, 6.08 ± 2.63, 41.39 ± 24.68, 8.0 ± 3.2; respectively. In Turner girls the ovarian reserve assessment indicated already diminished ovarian reserve. Ovarian stimulation and oocyte cryopreservation was successfully performed in all female children referred for fertility preservation. A range of 4-11 mature oocytes (mean 8.1 ± 3.4) was cryopreserved without any complications. All girls tolerated the procedure well.

CONCLUSIONS

Oocyte cryopreservation is a feasible technique in selected female children at risk for premature ovarian failure. Further studies would be beneficial to test the success of oocyte cryopreservation in young girls.

Reproductive choices and outcomes after freezing oocytes for medical reasons: a follow-up study

STUDY QUESTION

What reproductive choices do women make after they have cryopreserved oocytes for medical reasons?

SUMMARY ANSWER

Women who had cryopreserved oocytes for medical reasons and tried to become pregnant, either attempted natural conception or resorted to assisted reproduction with fresh oocytes.

WHAT IS KNOWN ALREADY

Women confronted with a risk of premature ovarian insufficiency, due to gonadotoxic therapy, ovarian surgery or genetic predisposition, have an indication to cryopreserve oocytes. Many of these women will retain ovarian function, thus will retain the possibility of natural conception. The added value of cryopreserved oocytes to reproductive outcomes is unknown as there is a lack of follow-up of women who have cryopreserved oocytes for medical reasons.

STUDY DESIGN, SIZE AND DURATION

This follow-up study included a cohort of 85 women who cryopreserved their oocytes for medical reasons between 2009 and 2012.

PARTICIPANTS/MATERIALS, SETTING AND METHODS

Medical data from women who cryopreserved their oocytes at the Centre for Reproductive Medicine in the Academic Medical Centre in Amsterdam were extracted and self-report questionnaires were disseminated. The collected data considered demographics, outcomes of ovarian stimulation, fertility-threatening treatments, menstrual cycle changes, pregnancy attempts and outcomes and intended plans for the cryopreserved oocytes.

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 68 women, followed up for an average 25.3 months, returned the questionnaire (response rate: 80%). None of the women had used her cryopreserved oocytes although 16 women had tried to conceive. Of these women, eight were trying to conceive naturally, five had conceived naturally within 2 months and three had conceived with assisted reproduction not requiring cryopreserved oocytes (two women with conventional IVF because of tubal pathology and endometriosis and one woman with IUI because of polycystic ovary syndrome). Three out of the eight pregnancies had resulted in live births, two resulted in miscarriages and three were ongoing. Most women (71%) intended to conceive with their cryopreserved oocytes as a last resource option.

LIMITATIONS, REASONS FOR CAUTION

Transferability of our findings is challenged by the small sample but positively affected by our high response rate. As the time span between cryopreservation of oocytes and follow-up was short, follow-up of the cohort should be repeated in 2 years.

WIDER IMPLICATIONS OF THE FINDINGS

After a mean follow-up of 2 years, none of the women with a medical reason to cryopreserve oocytes had used her oocytes. Women who were trying to conceive during follow-up were doing so without using their stored oocytes. It is unclear whether starting assisted reproduction while having cryopreserved oocytes is the most appropriate clinical decision. Our findings emphasize the relevance of taking the chances of natural conception into account in counselling women about cryopreservation of oocytes.

STUDY FUNDING/COMPETING INTERESTS

This study was not externally funded. There are no conflicts of interest to declare.

Transitions in endocrinology: treatment of Turner's syndrome during transition

Transition in health care for young patients with Turner's syndrome (TS) should be perceived as a staged but uninterrupted process starting in adolescence and moving into adulthood. As a condition associated with high risk of short stature, cardiovascular diseases, ovarian failure, hearing loss and hypothyroidism, TS requires the attention of a multidisciplinary team. In this review paper, we systematically searched the relevant literature from the last decade to discuss the array of problems faced by TS patients and to outline their optimal management during the time of transfer to adult service. The literature search identified 233 potentially relevant articles of which 114 were analysed. The analysis confirmed that all medical problems present during childhood should also be followed in adult life. Additionally, screening for hypertension, diabetes mellitus, dyslipidaemia, and osteoporosis is needed. After discharge from the paediatric clinic, there is still a long way to go.

Fertility in Turner syndrome

There is increasing interest in fertility and use of assisted reproductive technologies for women with Turner syndrome (TS). Current parenting options include adoption, surrogacy, and spontaneous and assisted reproduction. For women with TS, specific risks of pregnancy include higher than usual rates of spontaneous abortion, foetal anomaly, maternal morbidity and mortality. Heterologous fertility assistance using oocytes from related or unrelated donors is an established technique for women with TS. Homologous fertility preservation includes cryopreservation of the patient's own gametes prior to the progressive ovarian atresia known to occur: preserving either mature oocytes or ovarian tissue containing primordial follicles. Mature oocyte cryopreservation requires ovarian stimulation and can be performed only in postpubertal individuals, when few women with TS have viable oocytes. Ovarian tissue cryopreservation, however, can be performed in younger girls prior to ovarian atresia - over 30 pregnancies have resulted using this technique, however, none in women with TS. We recommend consideration of homologous fertility preservation techniques in children only within specialized centres, with informed consent using protocols approved by a research or clinical ethics board. It is essential that further research is performed to improve maternal and foetal outcomes for women with TS.

Update on Turner and Noonan syndromes

Turner syndrome (TS) and Noonan syndrome (NS) have short stature as a constant feature; however, both conditions can present clinicians with a challenging array of genetic, cardiovascular, developmental, and psychosocial issues. In recent years, important advances have been achieved in each of these areas. This article reviews these two syndromes and provides updates on recent developments in diagnostic evaluation, growth and development, psychological issues, and treatment options for patients with TS and NS.

Anti-Müllerian hormone: an ovarian reserve marker in primary ovarian insufficiency

Primary ovarian insufficiency (POI), also known as premature ovarian failure, is a disorder of infertility characterized by amenorrhoea, low estrogen levels and increased gonadotropin levels in women aged <40 years. POI is the result of premature exhaustion of the follicle pool or can be attributed to follicular dysfunction, for example, owing to mutations in the follicle-stimulating hormone receptor or steroidogenic cell autoimmunity. Moreover, advances in cancer therapeutics over the past decades have led to increasing survival rates for both paediatric and adult malignancies. Given the gonadotoxic effect of many cancer treatments, more women develop POI. A marker that predicts whether women are at risk of POI would, therefore, aid in early diagnosis and fertility counselling. Anti-Müllerian hormone (AMH), a growth factor produced solely by small, growing follicles in the ovary, might constitute such a marker, as serum levels of this hormone correlate strongly with the number of growing follicles. In addition, AMH could potentially help assess the progression of ovarian senescence, as serum AMH levels are independent of hypothalamic-pituitary-gonadal axis function and decrease to undetectable levels at menopause. In cancer survivors, serum AMH levels correlate with the extent of gonadal damage. In this Review, we provide an overview of the current studies that have measured AMH in women with POI of various aetiologies and discuss its possible application as a marker to determine ovarian reserve.