Amenorrhea and oligomenorrhea in the adolescent female are often the result of anovulation due to an immature hypothalamic-pituitary-ovarian axis. A careful history, physical examination and selected laboratory tests can help to differentiate this type of transient menstrual irregularity from the large number of endocrine and anatomic abnormalities that also present in this age group. The HPO axis is not fully mature at menarche. Since the positive feedback response to estrogen, which allows ovulation, is frequently absent in the immediate postmenarchial period, menstrual irregularity is common: 55% of cycles are anovulatory in the 1st year. With further maturation of the HPO axis a pattern of regular ovulatory cycles emerges. Basic evaluation is indicated if menarche does not occur by age 16 or if secondary sexual development does not begin by age 14. Secondary amenorrhea is the absence of menses for at least 3 months in a patient who previously had established cycles. Causes of amenorrhea in adolescents include pregnancy, drugs and systemic diseases, hypothalamic and pituitary amenorrhea, postpill amenorrhea, hyperprolactinemia, androgen resistance, congenital anomalies of the genital tract, and androgen excess.
Hilgers TW, 2004·The Medical and Surgical Practice of NaProTECHNOLOGY·
Amenorrhea and anovulation represent a spectrum of hypothalamic, pituitary, ovarian, and end-organ etiologies that must be differentiated through systematic hormonal and anatomical evaluation before treatment is initiated. NaProTECHNOLOGY integrates CrMS mucus charting with targeted biochemical testing to identify the level of dysfunction and guide ovulation induction or hormonal restoration appropriate to the specific cause.
A partially purified follicle-stimulating hormone preparation (human pituitary FSH) has been obtained from human pituitaries. The ovarian response to this preparation was studied in 7 amenorrheic women. The effect of human chorionic gonadotropin (HCG) was studied in addition. In 4 patients exhibiting no endometrial activity or only slight proliferation, HCG alone did not induce ovulation and had no effect on the size of the uterus, on the endometrium, or on the urinary excretion of estrogen and pregnanediol. In 2 patients showing endometrial proliferation, the administration of HCG alone was followed by ovulation, a secretory transformation of the endometrium, and a marked increase in urinary pregnanediol excretion. The administration of human pituitary FSH alone to 2 patients resulted in an increase in the size of the uterine cavity, in polycystic enlargement of the ovaries, and in a pronounced increase in urinary estrogen output. Treatment with human pituitary FSH followed by HCG produced in all patients polycystic enlargement of the ovaries, ovulation in 4 out of 5, and a secretory transformation of the endometrium in 3 out of these 5 patients. Ovulation was accompanied by a marked increase in the urinary excretion of both estrogen and pregnanediol.
Reimão Miller KA et al., 2026·Reproductive biomedicine online
This review explores whether the clomiphene citrate stair-step protocol (SSP) for ovulation induction in patients with polycystic ovary syndrome (PCOS) outperforms the traditional protocol. The following databases were searched: PubMed, Cochrane Library, ClinicalTrials.gov, EMBASE and Google Scholar from inception to 15 June 2025, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and with PROSPERO registration (CRD420251050294). Of 847 screened records, five randomized controlled trials were included (n = 520: n = 255; traditional protocol: n = 265). Analyses were conducted in Review Manager 5.4 using random-effects models. Risk ratios, mean differences and 95% confidence intervals were calculated. Heterogeneity was assessed with I², risk of bias with RoB2, certainty with GRADE and robustness with leave-one-out sensitivity analysis. The SSP increased ovulation rates compared with the traditional protocol (RR 1.28, 95% CI 1.10 to 1.49; five randomized controlled trials [RCTs], n = 520, I² = 0%). Clinical pregnancy also favoured SSP (RR 1.46, 95% CI 1.04 to 2.05; four RCTs, n = 460; I² = 0%), although this result was largely driven by one study. The SSP shortened treatment duration (mean difference -32.59 days, 95% CI -38.66 to -26.52 days; three RCTs, n = 320, I² = 83%). Endometrial thickness was similar (mean difference 0.32 mm, 95% CI -0.95 to 1.59 mm; four RCTs, n = 460, I² = 91%). SSP improves ovulation rate and shortens treatment without affecting endometrial thickness and may increase clinical pregnancy rates.
Clomiphene citrate (CC) is the first-line medication for inducing ovulation in women with polycystic ovary syndrome (PCOS). However, approximately 20% of patients with PCOS are resistant to CC. This study aims to identify reliable baseline predictors of CC resistance in infertile women with PCOS. A post-hoc analysis of a large, multicenter randomized controlled trial (PCOSAct trial) conducted in China. The current analysis comprised the 471 participants who were randomized to the active CC arm and completed the requisite follow-up. To identify potential candidate variables, we employed multivariable logistic and LASSO regression analyses. Within the framework of a multivariable logistic regression model, we also estimated the independent associations between the identified candidate variables and resistance to CC. Additionally, we plotted the Receiver Operating Characteristic (ROC) curve and utilized the DeLong method to compare the statistical differences in the area under the curve (AUC). Finally, we constructed a restricted cubic spline (RCS) logistic regression model to illustrate the dose-response relationship between continuous predictor variables and CC resistance. CC resistance was identified in 32 (6.8%) participants. Body Mass Index (BMI), Total Testosterone (TT), and Anti-Müllerian Hormone (AMH) were useful predictors of ovarian response to CC. The "T+BMI" dual-factor model demonstrated high discriminative power (AUC = 0.801) and was statistically comparable to the three-factor model including AMH (AUC = 0.818; P = 0.347). TT was the strongest individual predictor (OR = 2.73 per 1-unit), while BMI was the most significant modifiable risk factor (OR = 2.49 per 1-SD). A simplified "T + BMI" assessment provides comparable prognostic utility without the need for AMH testing. For patients at high risk of CC resistance, we recommend upfront use of aromatase inhibitors or low-dose gonadotropins. This strategy avoids ineffective treatment cycles and enables personalized ovulation induction. The study was registered on ClinicalTrials.gov under the identification number NCT01573858 on July 6, 2012.