Ovarian Tissue Cryopreservation for Fertility Preservation in Patients with Hemoglobin Disorders: A Comprehensive Review

Hemoglobin diseases like sickle cell disease (SCD) and β-thalassemia (BT) present fertility challenges for affected patients. SCD and BT result from abnormal hemoglobin production or structure and pose numerous health concerns. Despite medical advancements improving the quality of life or even providing cures, SCD and BT pose unique fertility concerns for women. Young women with these disorders already contend with reduced ovarian reserve and a narrower fertile window, a situation that is compounded by the gonadotoxic effects of treatments like medications, transfusions, stem cell transplants, and gene therapy. While crucial for disease control, these interventions may lead to reproductive health issues, increasing infertility and early menopause risks. Ovarian tissue cryopreservation (OTC) offers potential for future motherhood to women with hemoglobin disorders facing infertility related to curative treatments. OTC involves surgically removing, preparing, and freezing ovarian tissue containing primordial follicles capable of producing mature oocytes, offering advantages over oocyte cryopreservation alone. However, the application of OTC for patients with hemoglobin disorders presents unique challenges, including special health risks, financial barriers, and access to care. This comprehensive literature review delves into the current state of ovarian tissue cryopreservation for fertility preservation in patients with hemoglobin disorders. Empowering patients with informed reproductive choices in the context of their hemoglobin disorders stands as the ultimate goal.

Female Reproductive Health Outcomes after Hematopoietic Cell Transplantation for Sickle Cell Disease: Is Reduced Intensity Better Than Myeloablative Conditioning?

Curative therapy for sickle cell disease (SCD) through hematopoietic cell transplantation (HCT) is associated with a high level of risk for treatment-related gonadal dysfunction and future infertility. Both the myeloablative conditioning (MAC) and reduced-intensity conditioning (RIC) regimens used for SCD HCT are considered to carry a high risk for ovarian damage. Cyclophosphamide equivalent doses (CEDs) are thought to correlate with the degree of gonadal damage in pediatric oncology patients. We aimed to evaluate ovarian outcomes previously reported from our center, characterize the conditioning regimens as MAC or RIC, and calculate the CED for each regimen. The ovarian outcomes diminished ovarian reserve (DOR), as determined by an anti-Müllerian hormone (AMH) below the normal limits for age and assay or <5%, and premature ovarian insufficiency (POI), defined as a follicle-stimulating hormone (FSH) level >40 mIU/ML, are presented by conditioning regimen from 3 clinical studies from our center (2 published and 1 presented as an abstract in 2022). The studies were not mutually exclusive of patients. CEDs were calculated for each regimen. The CED ranged from 3388 to 9705 mg/m2 for MAC regimens and from 5600 to 18,750 mg/m2 for RIC regimens. DOR was observed in all regimens; however, in one study 2 patients had normal AMH levels after a fludarabine/melphalan regimen, and 1 patient had a normal AMH level after a fludarabine/melphalan/thiotepa regimen. Rates of POI were more variable and ranged from 40% to 100% after MAC regimens and from 0 to 100% after RIC regimens. Female patients with SCD who undergo HCT have very high rates of DOR after both MAC HCT and RIC HCT. Two of the 3 RIC regimens evaluated had higher CEDs than were seen in any of the MAC regimens evaluated. Rates of POI were more variable but may increase with time from transplantation. All SCD patients need to be counseled about the risk of infertility and provided information about fertility preservation.

Pregnancy and sickle cell disease: an overview of complications and suggested perinatal care

INTRODUCTION

Pregnancy in women with sickle cell disease (SCD) has been identified as high risk owing to increased incidence of materno-fetal complications across various studies and reports. These complications include consequences related to the underlying hemoglobinopathy; chronic anemia/associated inflammation, and pregnancy related including the risk for thromboembolism, bleeding and maternal mortality. Outcomes of neonates born to women with SCD has been suboptimal over the years with recent improvement due to strict monitoring, preventive and therapeutic measures. Much is yet to be unraveled regarding the optimal management of women with SCD during pregnancy, identifying target hemoglobin, delivery mode or timing among others.

AREAS COVERED

This review includes a summary of available data of the maternal and fetal outcomes; in addition to current recommendations for monitoring and management of women with SCD during pregnancy.

EXPERT OPINION

To have a successful pregnancy, women should be closely monitored, and interventions provided as needed to guarantee adequate management of anemia, as well as prevention, diagnosis and management of disease. They should also be educated regarding their reproductive health, emphasizing that pregnancy is possible, and achieving optimal results depends on providing adequate care in a health care facility with expertise in high-risk pregnancies and SCD.

Fertility preservation for pediatric patients with hemoglobinopathies: Multidisciplinary counseling needed to optimize outcomes

Hemoglobinopathies are autosomal recessive disorders that occur when genetic mutations negatively impact the function of hemoglobin. Common hemoglobinopathies that are clinically significant include sickle cell disease, alpha thalassemia, and beta thalassemia. Advancements in disease-modifying and curative treatments for the common hemoglobinopathies over the past thirty years have led to improvements in patient quality of life and longevity for those who are affected. However, the diseases, their treatments and cures pose infertility risks, making fertility preservation counseling and treatment an important part of the contemporary comprehensive patient care. Sickle cell disease negatively impacts both male and female infertility, primarily by testicular failure and decreased ovarian reserve, respectively. Fertility in both males and females with beta thalassemia major are negatively impacted by iron deposition due to chronic blood transfusions. Hematopoietic stem cell transplant (HSCT) is currently the only curative treatment for SCD and transfusion dependent beta thalassemia. Many of the conditioning regimens for HSCT contain chemotherapeutic agents with known gonadotoxicity and whole-body radiation. Although most clinical studies on toxicity and impact of HSCT on long-term health do not evaluate fertility, gonadal failure is common. Male fertility preservation modalities that exist prior to gonadotoxic treatment include sperm banking for pubertal males and testicular cryopreservation for pre-pubertal boys. For female patients, fertility preservation options include oocyte cryopreservation and ovarian tissue cryopreservation. Oocyte cryopreservation requires controlled ovarian hyperstimulation (COH) with ten to fourteen days of intensive monitoring and medication administration. This is feasible once the patient has undergone menarche. Follicular growth is monitored via transvaginal or transabdominal ultrasound, and hormone levels are monitored through frequent blood work. Oocytes are then harvested via a minimally invasive approach under anesthesia. Complications of COH are more common in patients with hemoglobinopathies. Ovarian hyperstimulation syndrome creates a greater risk to patients with underlying vascular, pulmonary, and renal injury, as they may be less able to tolerate fluids shifts. Thus, it is critical to monitor patients undergoing COH closely with close collaboration between the hematology team and the reproductive endocrinology team. Counseling patients and families about future fertility must take into consideration the patient's disease, treatment history, and planned treatment, acknowledging current knowledge gaps.

Knowledge gaps in reproductive and sexual health in girls and women with sickle cell disease

There is an immediate need to address long-standing questions about the reproductive health of girls and women with sickle cell disease (SCD). There are many SCD-related reproductive risks and uncertainties across girls' and women's reproductive life span, with particularly outstanding concerns about menstruation, contraception, fertility and pregnancy. Extant literature addressing women's reproductive health topics is mostly descriptive; there are few high-quality interventional studies. In 2020, the Centers for Disease Control and Prevention and the Foundation for Women and Girls with Blood Disorders convened an expert panel to assess the knowledge gaps in women's reproductive health in SCD. The panel identified significant limitations to clinical care due to the need for research. The panel also identified prominent barriers to research and care. In this report, we frame these issues, providing a roadmap for investigators, funding agencies, and policy makers to advance care for girls and women with SCD.

Hydroxycarbamide exposure and ovarian reserve in women with sickle cell disease in the Multicenter Study of Hydroxycarbamide

The application of modern ovarian reserve measures to women with sickle cell disease (SCD) may help answer longstanding questions about whether SCD or hydroxycarbamide (HC; also known as hydroxyurea) affect women's reproductive lifespan. Anti-Müllerian hormone (AMH), an established marker of ovarian reserve, is used to assess the ovarian follicle pool. We used a standard clinical assay to measure AMH in 285 banked samples from 93 female subjects with haemoglobin SS from the historic Multicenter Study of Hydroxyurea (MSH), which led to the United States Food and Drug Administration approval of HC for adults with SCD. No samples from the randomised portion of the MSH remain, so samples from the decade-long MSH follow-up studies were analysed. Most subjects were exposed to HC (86/93). The median AMH levels were lower in study subjects than in age- and sex-matched reference values. The median AMH levels consistent with diminished ovarian reserve, a risk factor for infertility, occurred in subjects starting at the age of 25-30 years; in healthy women, this occurs after the age of 40 years. In multivariate analysis, taking HC was independently associated with a low AMH (β = 0·001, 95% confidence interval -0·002 to 0·000; P = 0·006). These results suggest that ovarian reserve is prematurely reduced in women with haemoglobin SS and raise the possibility that HC contributes to this finding.

Longitudinal Description of Gonadal Function in Sickle-cell Patients Treated With Hematopoietic Stem Cell Transplant Using Alkylator-based Conditioning Regimens

OBJECTIVES

This study describes the hormone profiles for gonadal late effects after alkylator-based hematopoietic stem cell transplant (HSCT) regimens used for sickle-cell disease (SCD).

METHODS

This is a retrospective chart review of subjects followed in the post-HSCT clinic for sickle-cell disease. Patient demographics, pubertal development, characteristics of pre-HSCT disease severity, treatment before HSCT, conditioning regimens, presence of graft versus host disease and follicle-stimulating hormone, anti-Müllerian hormone (AMH), luteinizing hormone and testosterone were abstracted from the medical record.

RESULTS

Forty subjects (24 female individuals) with SCD were 9 (±4.3) years old at HSCT and 7.9 years (±5.6) from HSCT. At the time of transplant, 8% of female individuals and no male individuals were pubertal and 58% of female individuals and 38% of male individuals had been treated with hydroxyurea. Post-HSCT, all of the female individuals had diminished ovarian reserve on the basis of low AMH values and 10 of the pubertal female individuals (71%) had premature ovarian insufficiency defined as follicle-stimulating hormone >40 mIU/mL ×2. There was no ovarian recovery and AMH remained very low or undetectable up to 13 years post-HSCT. In male individuals, luteinizing hormone and testosterone levels were normal for age.

CONCLUSIONS

Post-HSCT for SCD, all female individuals had diminished ovarian reserve and most female individuals had POI, whereas male individuals had normal testosterone hormone production.

Sickle Cell Disease and Pregnancy

Sickle cell disease (SCD) is the most common inherited hemoglobinopathy and is associated with increased risk of complications and early mortality. Nowadays, with improved health care facilities, antibiotic prophylaxis, vaccination, and availability of drugs like hydroxyurea, the life expectancy of SCD patients has improved. More women are reaching reproductive age group and are expressing their desire to reproduce. Though SCD adversely affects pregnancy, leading to increased incidence of maternal and perinatal complications like pre-eclampsia, preterm labor, IUGR, abortions etc., adequate care throughout pregnancy ensures a better outcome. Also, recent advancements in the fields of prenatal diagnosis and preimplantation genetic diagnosis, help couples suffering from SCD to have a healthy baby. This paper focuses on the effects of SCD on pregnancy outcomes and effective management of complications during pregnancy, also comparing maternal and perinatal outcomes in studies conducted in different countries. The second part of the paper summarizes pregnancy management in SCD for better maternal and fetal outcomes.

Ovarian reserve in women with sickle cell disease

BACKGROUND

It has been proposed that ovarian sickling and/or iron overload in women with sickle cell disease (SCD) could contribute to gonadal dysfunction, but there are very few published studies. We hypothesised that the above phenomena might impair ovarian reserve.

METHODS

A total of 50 SCD patients were case-matched by age, ethnicity, and presence of regular cycles (28±5 days) with 73 patients without a known haemoglobinopathy who required anti-Müllerian hormone (AMH) assessment in a gynaecology clinic. SCD patients had AMH levels taken as part of routine care. The patients were case-controlled and matched with patients who had no haemoglobinopathy in a tertiary centre over a period of one year.

RESULTS

The mean AMH in the SCD case group was 7.6 pmol/l compared with 13.4 pmol/l in the control group (p<0.001). The AMH distributions were subsequently categorised. This showed that SCD patients had a significantly higher chance of having lower AMH in comparison with the control group (OR 2.6 (CI 1.1-6.5, P = 0.02). The proportion of women with AMH > 20 pmol/l was significantly lower in the SCD group (6%) in comparison with the control group (19%) (P = 0.04).

CONCLUSIONS

This is the first study showing that women of reproductive age with SCD are more likely to have a low ovarian reserve at a younger age in comparison with patients with no haemoglobinopathy.

Fertility challenges for women with sickle cell disease

INTRODUCTION

Sickle cell disease (SCD) represents one of the most common monogenic blood disorders worldwide, with an incidence of over 300,000 newborns affected per year. Reproductive challenges for men and women with SCD have been previously reviewed; however, evidence-based strategies to prevent and manage infertility and increase fecundity are lacking in women with SCD, which is one of the most important factors for quality of life. Areas covered: This review article summarizes the known risk factors for infertility, low fecundity, and premature menopause related to SCD. Expert commentary: Women with SCD have unique risk factors that may impact their ability to conceive, including chronic inflammation, oxidative stress, transfusion-related hemochromatosis, and ovarian sickling, causing ischemia and reperfusion injury to the ovary. Contraception is strongly recommended while on hydroxyurea therapy during reproductive years and discontinuing hydroxyurea for family planning and during pregnancy based on teratogenicity in animal studies. Hematopoietic stem cell transplantation (HSCT), the only curative therapy, sometimes involves conditioning regimens containing alkylating agents and total body irradiation that contribute to infertility and premature ovarian failure. Prior to HSCT or gene therapy, we strongly recommend referral to a reproductive endocrinologist to discuss fertility preservation and surrogacy options for all women with SCD.