Adolescent Fertility Preservation: Where Do We Stand Now

Adolescence is a period of flux for many body systems. While fertility potential typically increases after menarche, there are diseases where the opposite occurs and fertility preservation options need to be considered early. In cases of cancer, options vary by pubertal status and can include ovarian tissue cryopreservation, oocyte cryopreservation, sperm cryopreservation, and testicular tissue cryopreservation. Much remains to be learned about fertility and preservation options in those with differences in sexual development (DSDs); however, depending on the form of DSD, fertility preservation may not be necessary. Similarly, traditional fertility counseling in children with galactosemia may need to be changed, as data suggest that fertility rates attributed to other causes of premature ovarian insufficiency may not be as applicable to this disease. Adolescents with Turner's syndrome are at high risk for premature ovarian failure; therefore, it is important to consider options as early as possible since ovarian reserves are depleted quickly. On the other hand, transgender and gender diverse adolescents may even be able to undergo fertility preservation after starting hormone therapy. In all cases, there are additional ethical components including technical/surgical risks in childhood, offering experimental therapies without creating false hope and evaluating children's consent and assent capabilities that must be considered.

Pathophysiology and management of classic galactosemic primary ovarian insufficiency

Classic galactosemia is an inborn error of carbohydrate metabolism associated with early-onset primary ovarian insufficiency (POI) in young women. Our understanding of the consequences of galactosemia upon fertility and fecundity of affected women is expanding, but there are important remaining gaps in our knowledge and tools for its management, and a need for continued dialog so that the special features of the condition can be better managed. Here, we review galactosemic POI and its reproductive endocrinological clinical sequelae and summarize current best clinical practices for its management. Special consideration is given to the very early-onset nature of the condition in the pediatric/adolescent patient. Afterward, we summarize our current understanding of the reproductive pathophysiology of galactosemia, including the potential action of toxic galactose metabolites upon the ovary. Our work establishing that ovarian cellular stress reminiscent of endoplasmic reticulum (ER) stress is present in a mouse model of galactosemia, as well as work by other groups, are summarized.

LAY SUMMARY

Patients with the condition of classic galactosemia need to maintain a strict lifelong diet that excludes the sugar galactose. This is due to having mutations in enzymes that process galactose, resulting in the buildup of toxic metabolic by-products of the sugar. Young women with classic galactosemia often lose the function of their ovaries very early in life (termed 'primary ovarian insufficiency'), despite adherence to a galactose-restricted diet. This means that in addition to the consequences of the disease, these women also face infertility and the potential need for hormone replacement therapy. This article summarizes current strategies for managing the care of galactosemic girls and women and also what is known of how the condition leads to early primary ovarian insufficiency.

Fertility Preservation in Women: Indications and Options for Therapy

Fertility preservation (FP) is a vital issue for individuals in either reproductive or prepubescent stage of life when future fertility may be compromised. The objective of any FP intervention is to minimize or eliminate primary disease burden and to ensure maintaining or preserving reproductive health. Fertility potential can be affected by cancer therapy and numerous other factors, including advancing age, metabolic conditions, autoimmune diseases, specific surgical interventions, and sex affirmation procedures. A paradigm shift focusing on quality-of-life issues and long-term survivorship has emerged, especially because of advances in cancer diagnostics and treatment. Several FP techniques have been widely distributed, while others are still in the research stage. In addition, specific procedures and some potentially fertoprotective agents are being developed, aiming to minimize the hazards of gonadal damage caused by cancer therapy and decrease the need for more costly, invasive, and time-consuming FP methods. This review highlights the advances, indications, and options for FP, both experimental and well-established, in females of various age groups. An electronic search in PubMed, Embase, and Google Scholar databases was conducted, including retrospective studies, prospective clinical trials, meta-analyses, original reviews, and online abstracts published up to June 30, 2019. The search terms used included fertility preservation, oncofertility, embryo cryopreservation, oocyte cryopreservation, and ovarian tissue cryopreservation. The meeting proceedings of the American Society for Reproductive Medicine and the European Society of Human Reproduction and Embryology were also hand searched.

Nonmalignant diseases and treatments associated with primary ovarian failure: an expanded role for fertility preservation

Cancer treatments can be detrimental to fertility; recent literature has focused on the efforts of fertility preservation for this patient population. It should be recognized, however, that several nonmalignant medical conditions and therapeutic interventions could be similarly hazardous to fertility. Some of these nonmalignant diseases and their treatments that can adversely impact the reproductive axis are gastrointestinal diseases, rheumatologic disorders, nonmalignant hematologic conditions, neurologic disorders, renal disorders, gynecologic conditions, and metabolic diseases. Their negative effects on reproductive function are only now being appreciated and include impaired ovarian function, endocrine function, or sexual function and inability to carry a pregnancy to term. Complications and comorbidities associated with certain diseases may limit the success of established fertility preservation options. Recent advances in fertility preservation techniques may provide these patients with new options for childbearing. Here, we review several fertility-threatening conditions and treatments, describe current established and experimental fertility preservation options, and present three initiatives that may help minimize the adverse reproductive effects of these medical conditions and treatments by raising awareness of the issues and options: (1) increase awareness among practitioners about the reproductive consequences of specific diseases and treatments, (2) facilitate referral of patients to fertility-sparing or restorative programs, and (3) provide patient education about the risk of infertility at the time of diagnosis before initiation of treatment.

Ovarian function in Duarte galactosemia

OBJECTIVE

To determine if girls with Duarte variant galactosemia (DG) have an increased risk of developing premature ovarian insufficiency based on prepubertal anti-Müllerian hormone (AMH) levels.

DESIGN

Cross-sectional study.

SETTING

University research laboratory.

PATIENT(S)

Study volunteers included 57 girls with DG, 89 girls with classic galactosemia (GG), and 64 control girls between the ages of <1 month and 10.5 years.

INTERVENTION(S)

Blood sampling.

MAIN OUTCOME MEASURE(S)

We determined AMH and FSH levels in study volunteers with and without Duarte variant or GG.

RESULT(S)

FSH levels were significantly higher and AMH levels significantly lower in girls with GG than in age-stratified control girls, but there was no significant difference between FSH and AMH levels in girls with DG and control girls.

CONCLUSION(S)

Although >80% of girls with GG in this study demonstrated low to undetectable AMH levels consistent with diminished ovarian reserve, 100% of girls with DG in our study demonstrated no apparent decrease in AMH levels or increase in FSH levels, suggesting that these girls are not at increased risk for premature ovarian insufficiency.

Ovarian function in girls and women with GALT-deficiency galactosemia

Primary or premature ovarian insufficiency (POI) is the most common long-term complication experienced by girls and women with classic galactosemia; more than 80% and perhaps more than 90% are affected despite neonatal diagnosis and careful lifelong dietary restriction of galactose. In this review we explore the complexities of timing and detection of galactosemia-associated POI and discuss potential underlying mechanisms. Finally, we offer recommendations for follow-up care with current options for intervention.

Primary ovarian insufficiency

Primary ovarian insufficiency is a subclass of ovarian dysfunction in which the cause is within the ovary. In most cases, an unknown mechanism leads to premature exhaustion of the resting pool of primordial follicles. Primary ovarian insufficiency might also result from genetic defects, chemotherapy, radiotherapy, or surgery. The main symptom is absence of regular menstrual cycles, and the diagnosis is confirmed by detection of raised follicle-stimulating hormone and declined oestradiol concentrations in the serum, suggesting a primary ovarian defect. The disorder usually leads to sterility, and has a large effect on reproductive health when it arises at a young age. Fertility-preservation options can be offered to some patients with cancer and those at risk of early menopause, such as those with familial cases of primary ovarian insufficiency. Long-term deprivation of oestrogen has serious implications for female health in general; and for bone density, cardiovascular and neurological systems, wellbeing, and sexual health in particular.

Galactosemia and amenorrhea in the adolescent

Hereditary galactosemia is a biochemical genetic disease due to a deficiency of galactose-1-phosphate uridyltransferase (GALT) enzyme activity (OMIM 606999). Acute manifestations occur in the neonatal period and are, with rare exceptions, related to lactose ingestion. They include poor feeding and growth, emesis, jaundice, liver disease, bleeding diathesis, anemia, renal tubulopathy, cataracts, encephalopathy and death from E. coli sepsis. Chronic manifestations, which also develop in prospectively treated patients, involve (a) the brain, resulting in delayed language acquisition, speech defects, and learning problems, and (b) the ovary, in the majority of females, producing hypergonadotropic hypogonadism. The serum FSH level is elevated in infancy/early childhood in many, but not all patients with a severe phenotype. There are few reports of patients with classic galactosemia having undergone pregnancy, labor, and delivery. The pathologic findings in the ovary, including a persistence of primordial follicles and streak gonads, have been variable. The etiology of primary ovarian insufficiency (POI) in galactosemia is unknown. Clinical surveillance includes screening for abnormalities in ovarian function at an early age. Treatment consists of estrogen/progesterone supplementation at the appropriate age. Reduced BMD has been reported. Future research is needed (1) to delineate the mechanisms behind reduced ovarian function in these young women; (2) to determine the timing of the lesion: prenatal, postnatal, and both pre- and postnatal; (3) to determine whether elevated galactose-1-phosphate is both necessary and sufficient to induce primary ovarian insufficiency; and (4) to understand the mechanism(s) behind the reduced BMD seen in children and adolescents with galactosemia.

Biomarkers of ovarian function in girls and women with classic galactosemia

OBJECTIVE

To determine whether premature ovarian insufficiency (POI) associated with classic galactosemia results from a true impairment of ovarian function or from aberrant FSH.

DESIGN

Cross-sectional study.

SETTING

University research laboratory.

PATIENT(S)

Study subjects included 35 girls and women with galactosemia and 43 control girls and women between the ages of <1 and 51 years.

INTERVENTION(S)

Blood sampling and medical and reproductive histories were obtained.

MAIN OUTCOME MEASUREMENT(S)

We determined FSH and anti-Müllerian hormone (AMH) levels in subjects with and without classic galactosemia. FSH bioactivity was measured in a subset of girls and women with and without galactosemia who were not on hormone therapy.

RESULT(S)

FSH levels were significantly higher and AMH levels were significantly lower in our galactosemic cases relative to controls. FSH bioactivity did not significantly differ between cases and controls.

CONCLUSION(S)

Close to 90% of girls and women with classic galactosemia have a profound absence of ovarian function, a deficit that is evident shortly after birth, if not before. These patients have no evidence of abnormally functioning FSH. AMH levels can be assessed before menarche or after initiation of hormone therapy and may supplement FSH as a useful blood biomarker of ovarian function for patients with classic galactosemia.