Metabolic effects of oral versus transdermal 17β-estradiol (E₂): a randomized clinical trial in girls with Turner syndrome

Resting energy expenditure in girls with Turner syndrome

BACKGROUND

Knowledge concerning energy metabolism in Turner syndrome (TS) is lacking. We compared the resting energy expenditure per fat-free mass (REE/FFM) in TS with other girls with short stature treated with growth hormone (GH) and age-related controls.

METHODS

We measured prospectively REE by spirometry under fasting conditions in the morning in 85 short prepubertal girls at the start of GH treatment. Diagnoses were TS (n=20), GH deficiency (GHD) (n=38) and small for gestational age (SGA) short stature (n=27). Additionally, 20 age-related controls were studied. Mean ages were 8.3 (TS), 7.1 (GHD), 6.9 (SGA) and 8.5 years (controls). Mean heights were -2.90 (TS), -3.32 (GHD), -3.69 (SGA) and -0.03 standard deviation scores (SDS) (controls). FFM was measured by bioelectrical impedance analysis (BIA).

RESULTS

At the start of GH girls with TS showed insignificantly higher REE per FFM (REE/FFM) (mean±SD; 65±9 kcal/kg×day) than did the other female patients (62±9 kcal/kg×day) (p>0.23). The healthy controls had significantly lower REE/FFM (35±4 kcal/kg×day) (p<0.001). Follow-up examination of the patients after 6 or 12 months revealed decreasing REE/FFM in TS (62±9 kcal/kg×day) resulting in comparable REE/FFM in all three patient groups.

CONCLUSIONS

At baseline short girls with TS had insignificantly higher REE/FFM than short children with SGA or GHD, but in follow-up this difference was not detectable any more. Future studies are necessary to understand this observation.

Effect of estrogen replacement therapy on bone and cardiovascular outcomes in women with turner syndrome: a systematic review and meta-analysis

Patients with Turner syndrome have adverse bone and cardiovascular outcomes from chronic estrogen deficiency. Hence, long-term estrogen replacement therapy is the cornerstone treatment. The estimates of its effect and optimal use, however, remain uncertain. We aimed to summarize the benefits and harms of estrogen replacement therapy on bone, cardiovascular, vasomotor and quality of life outcomes in patients with Turner syndrome. A comprehensive search of four databases was performed from inception through January 2016. Randomized clinical trials and observational cohort studies studying the effect of estrogen replacement therapy in patients with Turner syndrome under the age of 40 were included. Independently and in duplicate reviewers selected studies, extracted data and assessed risk of bias. Subgroup analyses were based on route of administration and type of estrogen formulation. Twenty-five studies at moderate to high risk of bias (12 randomized trials, 13 cohort studies) with 771 patients were included. Using random-effects models, estrogen replacement therapy showed an increase in bone mineral density [weighted mean change from baseline 0.09 g/cm2 (0.04-0.14)] that differed by type of estrogen but not route of administration. Oral estrogen replacement therapy showed a higher increase in high density lipoprotein cholesterol levels when compared to transdermal [weighted mean difference 9.33 mg/dl (4.82-13.85)] with no significant effect on other lipid fractions. The current evidence suggests possible benefit of estrogen replacement therapy on bone mineral density and high density lipoprotein cholesterol. Whether this improvement translates into changes in patient important outcomes (cardiovascular events or fractures) remains uncertain. Larger randomized clinical trials with direct comparisons on patient important outcomes are necessary.

Dosage of estradiol, bone and body composition in Turner syndrome: a 5-year randomized controlled clinical trial

OBJECTIVE

Reduced bone mineral density (BMD) is seen in Turner syndrome (TS) with an increased risk of fractures, and body composition is characterized by increased body fat and decreased lean body mass. To evaluate the effect of two different doses of oral 17B-estradiol in young TS women on bone mineral density (BMD), biochemical markers of bone turnover and body composition with the hypothesis of a positive effect of the higher dose.

DESIGN

A double-blind 5-year randomized controlled clinical trial. 20 young TS women participated. Inclusion criteria were diagnosis of TS, age 15-25 years and current treatment with 2 mg oral estradiol daily.

METHODS

The low-dose (LD) group was administered 2 mg 17B-estradiol/day orally and placebo, the high-dose (HD) group was administered 2 + 2 mg 17B-estradiol/day orally. Main outcome measures were whole body and regional bone mineral density (BMD), lean body mass (LBM), fat mass (FM) measured yearly by DXA scan and resorptive and formative bone markers in serum.

RESULTS

BMD, whole body and regional, increased over time with an attenuation toward the end of the study, and bone turnover markers decreased over time, both with no differences between the treatment groups (P = 0.2-0.9). LBM increased significantly more in the HD group (P = 0.02). FM remained stable in both groups.

CONCLUSIONS

A steady increase in BMD over time in TS was found similar to healthy young women. The higher estrogen dose did not differentially affect BMD or bone markers. The positive effect on body composition may have long-ranging health benefits in TS.

Review and Recommendations on Management of Adult Female Thalassemia Patients with Hypogonadism based on Literature Review and Experience of ICET-A Network Specialists

BACKGROUND

Multi-transfused thalassemia major (TM) patients frequently develop severe endocrine complications, mainly due to iron overload, anemia, and chronic liver disease, which require prompt diagnosis, treatment and follow-up by specialists. The most common endocrine complication documented is hypogonadotropic hypogonadism which increases with age and associated comorbidities. It is thus important for physicians to have a clear understanding of the pathophysiology and management of this disorder. Also to be aware of the side effects, contraindications and monitoring of sex steroid therapy. In this paper, practical ICET-A recommendations for the management of hypogonadism in adult females with TM are addressed.

METHODS

In March 2015, the Coordinator of the International Network of Clinicians for Endocrinopathies in Thalassemia and Adolescent Medicine (ICET-A) conducted a two-step survey to assess the attitudes and practices of doctors in the ICET-A network taking care of adult female TM patients with hypogonadism. They were clinically characterized by the absence of pubertal development or discontinuation or regression of the maturation of secondary sex characteristics, and biochemically by persistent low FSH, LH and estradiol levels. Recently a supplementary survey on adult female hypogonadism in TM was undertaken within the ICET-A network.

RESULTS

The completed questionnaires were returned by 16 of 27 specialists (59.2%) following 590 female TM patients over the age of 18 years; 315 patients (53.3%) had hypogonadism, and only 245 (74.6%) were on hormone replacement therapy (HRT). Contraceptive oral pills (COC) were the first treatment choice in 11 centers (68.7%). A wide range of COCs was used with different progestin contents. In general, the patients' compliance to treatment was reported as good in 81.2 % of centers. The frequency of required tests for follow-up HRT, in addition to the regular check-up for thalassemia, was variable in the participating centers.

CONCLUSIONS

Doctors taking care of TM patients should have sound knowledge of the pathophysiology of hypogonadism in adult females with TM. They should know the potential effects of HRT including advantages and disadvantages of estrogen and progestins. Moreover, they should keep in consideration the emotional needs of these patients dreaming of attaining a full pubertal development.

Weight gain in Turner Syndrome: association to puberty induction? - longitudinal analysis of KIGS data

CONTEXT

Girls with Turner Syndrome (TS) treated or not treated with growth hormone (GH) are prone to overweight. Therefore, we hypothesize that puberty induction in TS is associated with weight gain.

METHODS

We analyzed weight changes (BMI-SDS) between onset of GH treatment and near adult height (NAH) in 887 girls with TS enrolled in KIGS (Pfizer International Growth Database). Puberty was induced with estrogens in 646 (72·8%) girls with TS.

RESULTS

Weight status did not change significantly between GH treatment start and 1 year later (mean difference -0·02 BMI-SDS), but increased significantly (P < 0·001) until NAH (+0·40 BMI-SDS). The BMI-SDS increased +0·21 until start of puberty (P < 0·001). Girls with spontaneous and induced puberty showed similar BMI-SDS changes. Puberty induction at ≥12 years was associated with a significant (P < 0·001) less increase of BMI-SDS (+0·7 BMI-SDS) between baseline and NAH compared to puberty induction at <12 year (+1·0 BMI-SDS). In multiple linear regression analyses changes of BMI-SDS between baseline and NAH were negatively associated with baseline BMI-SDS (P < 0·001), GH doses (P = 0·015), and age at puberty induction (P < 0·001), positively with years on GH treatment (P = 0·004), while duration and dose of estrogens, its route of administration (transdermal/oral), changes of height-SDS, thyroxin and oxandrolone treatment, and karyotype did not correlate significantly to changes of BMI-SDS in this time period.

CONCLUSIONS

Puberty does not seem to play a major role in weight gain in girls with TS since the majority of the increases in BMI-SDS occurred before puberty. However, late puberty induction seems to decrease the risk of weight gain.

Is there a role for estrogen activity assays? Recombinant cell bioassay for estrogen: Development and applications

There are many questions which cannot be answered without a very sensitive estradiol assay. A recombinant cell bioassay (RCBA) for estradiol was developed in 1994. The sensitivity of the bioassay is 0.02-0.2 pg/ml (0.07-0.7 pmol/L), more than 20 times more sensitive than commercial RIAs and 10 times more sensitive than newer mass spectrometry assays. The RCBA for estradiol opened the door to study low levels of estradiol equivalents (EE) across the physiological spectrum of life from prepubertal children through menopause and across the spectrum from normal physiology, in boys as well as girls, to pathology, including: premature thelarche; estradiol suppression in children treated with GnRH analogues for precocious puberty; aromatase inhibition in boys with growth hormone deficiency; the differences between oral and transdermal routes of estrogen administration in girls with Turner's syndrome; women with breast cancer treated with aromatase inhibitors; and women with urogenital atrophy treated with low dose vaginal estrogen. A bioassay also allows study of endocrine disruptors, like phytoestrogens and other environmental compounds, which are relevant to public health and alternative medicine options. This paper reviews the assay and the last 20 years of applications. A bioassay for estrogen has a role because measuring biological effect is theoretically useful, increasing the understanding of physiology in addition to biochemical levels, giving different information than other assays, and opening the door to measure very low levels of estrogen activity in both humans and the environment.

Estradiol assays--The path ahead

Estradiol quantitation is useful in the clinical assessment of diseases like hypogonadism, hirsutism, polycystic ovary syndrome (PCOS), amenorrhea, ovarian tumors and for monitoring response in women receiving aromatase inhibitor therapy. Physiologically relevant serum estradiol concentration in women can span across four orders of magnitude. For example, in women undergoing ovulation induction serum estradiol concentration can range between 250-2000 pg/mL whereas aromatase inhibitor therapy can decrease serum estradiol concentration to <5 pg/mL. While high-through-put automated un-extracted (direct) immunoassays accommodate the growing clinical need for estradiol quantitation, are amenable to implementation by most hospital clinical laboratories, they display a significant loss of specificity and accuracy at low concentrations. Most clinical scenarios (example: estradiol monitoring in fertility treatments) place a modest demand on accuracy and precision of the assay in use but accurate quantitation of estradiol in certain clinical scenarios (pediatric and male patients and for monitoring aromatase inhibitor therapy) can be challenging using currently available immunoassays since the direct immunoassays are prone to issues with sub-optimal accuracy and specificity due to cross reactivity with estradiol conjugates and metabolites. In this review we discuss the bases for the evolution of estradiol assays from extracted (indirect) radio-immunoassays to direct immunoassays to liquid-chromatography tandem mass spectrometry (LC-MS/MS) based assays, discuss technical factors relevant for development and optimization of a LC-MS/MS assay for estradiol and present the details and performance characteristics of an ultra-sensitive LC-MS/MS estradiol assay with a limit of quantitation of 0.2 pg/mL.

The muscle-bone interaction in Turner syndrome

OBJECTIVES

Turner syndrome (TS) is associated with an increased fracture rate due to reduced bone strength, which is mainly determined by skeletal muscle force. This study aimed to assess the muscle force-bone strength relationship in TS and to compare it with that of healthy controls.

METHODS

This study included 39 girls with TS and 67 healthy control girls. Maximum muscle force (Fmax) was assessed through multiple one-legged hopping with jumping mechanography. Peripheral quantitative computerized tomography assessed the bone strength index at the tibial metaphysis (BSI 4) and the polar strength-strain index at the diaphysis (SSI polar 66). The effect of TS on the muscle-bone unit was tested using multiple linear regression.

RESULTS

TS had no impact on Fmax (p=0.14); however, a negative effect on bone strength (p<0.001 for BSI 4 and p<0.01 for SSI polar 66) was observed compared with healthy controls. Bone strength was lower in the TS group (by 18%, p<0.01, for BSI 4 and by 7%, p=0.027, for SSI polar 66), even after correcting for Fmax.

CONCLUSIONS

Similar muscle force induces lower bone strength in TS compared with healthy controls, which suggests altered bone-loading sensitivity in TS.

Proceedings from the Turner Resource Network symposium: the crossroads of health care research and health care delivery

Turner syndrome, a congenital condition that affects ∼1/2,500 births, results from absence or structural alteration of the second sex chromosome. There has been substantial effort by numerous clinical and genetic research groups to delineate the clinical, pathophysiological, cytogenetic, and molecular features of this multisystem condition. Questions about the molecular-genetic and biological basis of many of the clinical features remain unanswered, and health care providers and families seek improved care for affected individuals. The inaugural "Turner Resource Network (TRN) Symposium" brought together individuals with Turner syndrome and their families, advocacy group leaders, clinicians, basic scientists, physician-scientists, trainees and other stakeholders with interest in the well-being of individuals and families living with the condition. The goal of this symposium was to establish a structure for a TRN that will be a patient-powered organization involving those living with Turner syndrome, their families, clinicians, and scientists. The TRN will identify basic and clinical questions that might be answered with registries, clinical trials, or through bench research to promote and advocate for best practices and improved care for individuals with Turner syndrome. The symposium concluded with the consensus that two rationales justify the creation of a TRN: inadequate attention has been paid to the health and psychosocial issues facing girls and women who live with Turner syndrome; investigations into the susceptibility to common disorders such as cardiovascular or autoimmune diseases caused by sex chromosome deficiencies will increase understanding of disease susceptibilities in the general population.

Long-term health consequences of premature or early menopause and considerations for management

AIM

To review the current evidence concerning the long-term harmful effects of premature or early menopause, and to discuss some of the clinical implications.

MATERIAL AND METHODS

Narrative review of the literature.

RESULTS

Women undergoing premature or early menopause, either following bilateral salpingo-oophorectomy or because of primary ovarian insufficiency, experience the early loss of estrogen and other ovarian hormones. The long-term consequences of premature or early menopause include adverse effects on cognition, mood, cardiovascular, bone, and sexual health, as well as an increased risk of early mortality. The use of hormone therapy has been shown to lessen some, although not all of these risks. Therefore, multiple medical societies recommend providing hormone therapy at least until the natural age of menopause. It is important to individualize hormone therapy for women with early estrogen deficiency, and higher dosages may be needed to approximate physiological concentrations found in premenopausal women. It is also important to address the psychological impact of early menopause and to review the options for fertility and the potential need for contraception, if the ovaries are intact.

CONCLUSIONS

Women who undergo premature or early menopause should receive individualized hormone therapy and counseling.

Commentary: Launch of a quality improvement network for evidence-based management of uncommon pediatric endocrine disorders: Turner syndrome as a prototype

BACKGROUND

Traditional, hypothesis-oriented research approaches have thus far failed to generate sufficient evidence to achieve consensus about the management of children with many endocrine disorders, partly because of the rarity of these disorders and because of regulatory burdens unique to research in children.

OBJECTIVE

The Pediatric Endocrine Society is launching a quality improvement network in spring 2015 for the management of pediatric endocrine disorders that are relatively uncommon in any single practice and/or for which there is no consensus on management.

DESIGN

The first of the quality improvement programs to be implemented seeks to improve the care of 11- to 17-year-old girls with Turner syndrome who require initiation of estrogen replacement therapy by providing a standardized clinical assessment and management plan (SCAMP) for transdermal estradiol treatment to induce pubertal development. The SCAMP algorithm represents a starting point within current best practice that is meant to undergo refinement through an iterative process of analysis of deidentified data collected in the course of clinical care by a network of pediatric endocrinologists.

CONCLUSION

It is anticipated that this program will not only improve care, but will also result in actionable data that will generate new research hypotheses and changes in management of pediatric endocrine disorders.

Effect of oxandrolone and timing of oral ethinylestradiol initiation on pubertal progression, height velocity and bone maturation in the UK Turner study

BACKGROUND

A UK study showed final height in Turner syndrome (TS) girls receiving growth hormone is affected by age at pubertal induction and oxandrolone (Ox). Using data from that study, we analysed the effect of timing of oral ethinylestradiol (EE2) and Ox on height velocity (HV), bone maturation and pubertal progression, and compared growth response in EE2-treated versus spontaneous puberty.

METHODS

Analysis of HV, bone age and pubertal stage in 92 TS girls (7-13 years) randomised to Ox (0.05 mg/kg/day; max: 2.5 mg/day) or placebo from 9 years, and EE2 (year 1: 2 µg/day; year 2: 4 µg/day; year 3: 6/8/10 µg/day×4 months) or placebo at 12 years with EE2 at 14 years. Girls enrolled at >12.25 years received EE2 at 14 years ('late group').

RESULTS

Fifty-six girls were randomised to EE2 at 12 years (n=28, 11 Ox) or 14 years (n=28, 13 Ox); there were 19 girls in the late group (9 Ox) and 17 girls with spontaneous puberty (10 Ox). Girls receiving EE2 at 12 versus 14 years had faster bone maturation, but neither group showed acceleration. Ox increased HV without altering bone maturation or pubertal progression. Girls with spontaneous puberty had greater pubertal growth (mean PHV 8.5 cm/year; p<0.001) and height gain (p<0.001) than EE2-treated girls despite similar mean enrolment height SD and dysmorphology scores.

CONCLUSION

Pubertal induction with EE2 does not replicate the acceleration observed in unaffected girls or TS girls with spontaneous puberty.

Turner syndrome: update on biology and management across the life span

PURPOSE OF REVIEW

We review recent understanding of the pathophysiology, molecular biology, and management of Turner syndrome.

RECENT FINDINGS

Sophisticated genetic techniques are able to detect mosaicism in one-third of individuals previously thought to have monosomy X. Prenatal detection using maternal blood should permit noninvasive detection of most fetuses with an X chromosome abnormality. Disproportionate growth with short limbs has been documented in this condition, and a target gene of short stature homeobox, connective tissue growth factor (Ctgf), has been described. Liver disease is more common in Turner syndrome than previously recognized. Most girls have gonadal failure. Spontaneous puberty and menarche is more commonly seen in girls with XX mosaicism. Low-dose estrogen replacement therapy may be given early to induce a more normal onset and tempo of puberty. Oocyte donation for assisted reproduction carries a substantial risk, particularly if the woman has known cardiac or aortic disease. Neurodevelopmental differences in Turner syndrome are beginning to be correlated with differences in brain anatomy.

SUMMARY

An increased understanding of the molecular basis for aspects of this disorder is now developing. In addition, a renewed focus on health maintenance through the life span should provide better general and targeted healthcare for these girls and women.

Effects of low-dose estrogen replacement during childhood on pubertal development and gonadotropin concentrations in patients with Turner syndrome: results of a randomized, double-blind, placebo-controlled clinical trial

CONTEXT

The optimal approach to estrogen replacement in girls with Turner syndrome has not been determined.

OBJECTIVE

The aim of the study was to assess the effects of an individualized regimen of low-dose ethinyl estradiol (EE2) during childhood from as early as age 5, followed by a pubertal induction regimen starting after age 12 and escalating to full replacement over 4 years.

DESIGN

This study was a prospective, randomized, double-blind, placebo-controlled clinical trial.

SETTING

The study was conducted at two US pediatric endocrine centers.

SUBJECTS

Girls with Turner syndrome (n = 149), aged 5.0-12.5 years, were enrolled; data from 123 girls were analyzable for pubertal onset.

INTERVENTION(S)

Interventions comprised placebo or recombinant GH injections three times a week, with daily oral placebo or oral EE2 during childhood (25 ng/kg/d, ages 5-8 y; 50 ng/kg/d, ages >8-12 y); after age 12, all patients received escalating EE2 starting at a nominal dosage of 100 ng/kg/d. Placebo/EE2 dosages were reduced by 50% for breast development before age 12 years, vaginal bleeding before age 14 years, or undue advance in bone age.

MAIN OUTCOME MEASURES

The main outcome measures for this report were median ages at Tanner breast stage ≥2, median age at menarche, and tempo of puberty (Tanner 2 to menarche). Patterns of gonadotropin secretion and impact of childhood EE2 on gonadotropins also were assessed.

RESULTS

Compared with recipients of oral placebo (n = 62), girls who received childhood low-dose EE2 (n = 61) had significantly earlier thelarche (median, 11.6 vs 12.6 y, P < 0.001) and slower tempo of puberty (median, 3.3 vs 2.2 y, P = 0.003); both groups had delayed menarche (median, 15.0 y). Among childhood placebo recipients, girls who had spontaneous breast development before estrogen exposure had significantly lower median FSH values than girls who did not.

CONCLUSIONS

In addition to previously reported effects on cognitive measures and GH-mediated height gain, childhood estrogen replacement significantly normalized the onset and tempo of puberty. Childhood low-dose estrogen replacement should be considered for girls with Turner syndrome.

Current concepts surrounding bone health and osteoporosis in Turner syndrome

Although Turner syndrome is the most common chromosomal disorder in women, a great deal remains to be understood in terms of optimal patient care, particularly as it relates to bone health. These women are known to be at risk for osteoporosis and fracture later in life as a result of a multitude of risk factors. While estrogen replacement and childhood growth hormone treatment are now considered standard of care, little is known of the role of further interventions to prevent and treat osteoporosis in these women. This review aims to highlight the specifics of bone health in Turner syndrome. We explore the bone diagnostic modalities and therapeutic interventions available and their role in the coming years of bone health management in this unique population.

A randomized trial of transdermal and oral estrogen therapy in adolescent girls with hypogonadism

Background

Adolescent females with ovarian failure require estrogen therapy for induction of puberty and other important physiologic effects. Currently, health care providers have varying practices without evidence-based standards, thus investigating potential differences between oral and transdermal preparations is essential. The purpose of this study was to compare the differential effects of treatment with oral conjugated equine estrogen (OCEE), oral 17β estradiol (OBE), or transdermal 17β estradiol (TBE) on biochemical profiles and feminization in girls with ovarian failure.

Study design

20 prepubertal adolescent females with ovarian failure, ages 12–18 years, were randomized to OCEE (n = 8), OBE (n = 7), or TBE (n = 5) for 24 months. Estrogen replacement was initiated at a low dose (0.15 mg OCEE, 0.25 mg OBE, or 0.0125 mg TBE) and doubled every 6 months to a maximum dose of 0.625 mg/d OCEE, 1 mg/d OBE, or 0.05 mg/d TBE. At 18 months, micronized progesterone was added to induce menstrual cycles. Biochemical markers including sex hormones, inflammatory markers, liver enzymes, coagulation factors, and lipids were obtained at baseline and 6 month intervals. Differences in levels of treatment parameters between the groups were evaluated with one-way analysis of variance (ANOVA). The effect of progesterone on biochemical markers was evaluated with the paired t-test.

Results

Mean (±SE) estradiol levels at maximum estrogen dose (18 months) were higher in the TBE group (53 ± 19 pg/mL) compared to OCEE (14 ± 5 pg/mL) and OBE (12 ± 5 pg/mL) (p ≤ 0.01). The TBE and OBE groups had more effective feminization (100% Tanner 3 breast stage at 18 months). There were no statistical differences in other biochemical markers between treatment groups at 18 months or after the introduction of progesterone.

Conclusions

Treatment with transdermal 17β estradiol resulted in higher estradiol levels and more effective feminization compared to oral conjugated equine estrogen but did not result in an otherwise different biochemical profile in this limited number of heterogeneous patients. OBE and TBE provide safe and effective alternatives to OCEE to induce puberty in girls, but larger prospective randomized trials are required.

Trial registration

Clinical Trials Identifier: NCT01023178.

Turner's syndrome: challenges of late diagnosis

Girls and women with Turner's syndrome who come to medical attention older than 12 years present a challenge of medical management. Puberty is already delayed and some compromises have to be made in adjusting the timing of artificially induced puberty to optimise overall outcome with respect to stature, secondary sex characteristics, and psychosocial endpoints. Additionally, individuals who present with primary amenorrhoea to adult services might miss the opportunity for effective growth hormone treatment. Further, induction of puberty regimens lack an evidence base or even clear guidelines for the timing and dose of oestrogen replacement. We have searched the scientific literature to inform management of Turner's syndrome.

Clinical review: Adolescent anovulation: maturational mechanisms and implications

CONTEXT

Adolescents are at high risk for menstrual dysfunction. The diagnosis of anovulatory disorders that may have long-term health consequences is too often delayed.

EVIDENCE ACQUISITION

A review of the literature in English was conducted, and data were summarized and integrated from the author's perspective.

MAIN FINDINGS

Normal adolescent anovulation causes only minor menstrual cycle irregularity: most cycles range from 21-45 days, even in the first postmenarcheal year, 90% by the fourth year. Approximately half of symptomatic menstrual irregularity is due to neuroendocrine immaturity, and half is associated with increased androgen levels. The former is manifest as aluteal or short/deficient luteal phase cycles and usually resolves spontaneously. The latter seems related to polycystic ovary syndrome because adolescent androgen levels are associated with adult androgens and ovulatory dysfunction, but data are sparse. Obesity causes hyperandrogenemia and, via unclear mechanisms, seems to suppress LH; it may mimic polycystic ovary syndrome. The role of pubertal insulin resistance in physiological adolescent anovulation is unclear. High-sensitivity gonadotropin and steroid assays, the latter by specialty laboratories, are necessary for accurate diagnosis of pubertal disorders. Polycystic ovaries are a normal ultrasonographic finding in young women and are associated with nearly 2-fold increased anti-Müllerian hormone levels. Oral contraceptives are generally the first-line treatment for ongoing menstrual dysfunction, and the effects of treatment are similar among preparations.

CONCLUSIONS

Menstrual cycle duration persistently outside 21-45 days in adolescents is unusual, and persistence ≥ 1 year suggests that disordered hypothalamic-pituitary-gonadal function be considered. Research is needed on the mechanisms and prognosis of adolescent anovulation.