World Health Organization multicenter study on menstrual and ovulatory patterns in adolescent girls. II. Longitudinal study of menstrual patterns in the early postmenarcheal period, duration of bleeding episodes and menstrual cycles
World Health Organization Task Force on Adolescent Reproductive Health
During a two-year study, 670 girls (aged 11-15 years) submitted menstrual diaries that started at the onset of their first menstrual bleeding (Group I), and 802 girls (aged 11-15 years) who had already experienced menarche prior to the study (Group II) kept similar diaries. The two groups were recruited in three centers: Colombo (urban), Peradeniya (rural), both in Sri Lanka, and Hong Kong. The mean duration of bleeding episodes was 4.7 days (SD 1.8) in Group I and 4.9 days (SD 1.4) in Group II. The median length of the first cycle after menarche was 34 days, with 38.3% of the cycles being longer than 40 days. By the 5th cycle the median length was 31 days, similar to that of Group II. The establishment of cycle regularity was defined by three successive cycles within the range of 10 days with none of the three cycles shorter than 20 or longer than 40 days. This regularity was achieved by 19% of the Group I girls in the first three cycles and by 67% of these girls during the entire study period, compared to 89% in Group II.
PMID 3721946 3721946 World Health Organization Task Force on Adolescent Reproductive Health et al. 1986, World Health Organization Task Force on Adolescent Reproductive Health 1986
Cite this article
World Health Organization Task Force on Adolescent Reproductive Health (1986). World Health Organization multicenter study on menstrual and ovulatory patterns in adolescent girls. II. Longitudinal study of menstrual patterns in the early postmenarcheal period, duration of bleeding episodes and menstrual cycles. Journal of Adolescent Health Care.
World Health Organization Task Force on Adolescent Reproductive Health. World Health Organization multicenter study on menstrual and ovulatory patterns in adolescent girls. II. Longitudinal study of menstrual patterns in the early postmenarcheal period, duration of bleeding episodes and menstrual cycles. Journal of Adolescent Health Care. 1986.
World Health Organization Task Force on Adolescent Reproductive Health. "World Health Organization multicenter study on menstrual and ovulatory patterns in adolescent girls. II. Longitudinal study of menstrual patterns in the early postmenarcheal period, duration of bleeding episodes and menstrual cycles." Journal of Adolescent Health Care, 1986.
Wesselink AK et al., 2016·Ann Epidemiol·
Open Access
The aim of this study was to evaluate the association between menstrual cycle characteristics in early life and adulthood and fecundability. Pregnancy Study Online (PRESTO) is an Internet-based preconception cohort study of pregnancy planners from the United States and Canada. During the preconception period, we enrolled 2189 female pregnancy planners aged 21-45 years who had been attempting conception for ≤6 cycles. Women self-reported menstrual cycle characteristics via an online baseline questionnaire, and pregnancy status was ascertained through bimonthly follow-up questionnaires. Proportional probabilities models were used to estimate fecundability ratios (FRs) and 95% confidence intervals (CIs), adjusting for potential confounders. Compared with usual menstrual cycle lengths of 27-29 days, cycle lengths of <25 (FR = 0.81, 95% CI: 0.54-1.22) and 25-26 days (FR = 0.92, 95% CI: 0.75-1.14) were associated with reduced fecundability. Compared with women who reached menarche at the age of 12-13 years, those who reached menarche at <12 years had reduced fecundability (FR = 0.87, 95% CI: 0.76-0.99). Women whose cycles never regularized after menarche (FR = 0.93, 95% CI: 0.81-1.06) had slightly reduced fecundability compared with women whose cycles regularized within 2 years of menarche. Bleed length and heaviness of bleeding were not appreciably associated with fecundability. Menstrual cycle characteristics, specifically cycle length and age at menarche, may act as markers of fertility potential among pregnancy planners.
The onset of puberty has been a fascinating topic for reproductive endocrinologists for decades; however, its underlying physiological mechanisms have remained elusive until recently. The discovery and understanding of the effects exerted by the peptide hormone kisspeptin have shed light on this research area. This review is aimed to discuss the functions of kisspeptin, with special focus on its role in the onset of puberty and in the ovulatory mechanism. The points under discussion are (1) the characteristics of kisspeptin and its receptor, (2) the relevance of this hormone and its interaction with leptin in the onset of puberty, (3) the role of kisspeptin in the ovulatory mechanism based on its differential expression at hypothalamic nuclei, which is modulated by sex steroid hormones, and (4) the clinical relevance of kisspeptin and its antagonists in new therapeutic strategies for the treatment of various reproductive pathologies. All of this explains the revolution that kisspeptin has caused among researchers working in the field of gynecological endocrinology and reproductive biology.
Bremer AA, 2010·Metab Syndr Relat Disord·
Open Access
Polycystic ovary syndrome (PCOS) is a common disorder characterized by hyperandrogenism and disordered gonadotropin secretion, often associated with insulin resistance. The syndrome, which modulates both hormonal and metabolic processes, is the most common endocrinopathy in reproductive-age women and increases a woman's risk of infertility, endometrial pathology, and cardiometabolic disease. As it is currently defined, PCOS most likely encompasses several distinct diseases with similar clinical phenotypes but different underlying pathophysiological processes. However, hyperandrogenism remains the syndrome's clinical hallmark. The clinical manifestations of PCOS often emerge during childhood or in the peripubertal years, suggesting that the syndrome is influenced by fetal programming and/or early postnatal events. However, given that the full clinical spectrum of PCOS does not typically appear until puberty, a "two-hit" hypothesis has been proposed: (1) a girl develops hyperandrogenism via one or more of many different potential mechanisms; (2) the preexisting hyperandrogenism subsequently disturbs the hypothalamic–pituitary–ovarian axis, resulting in ovulatory dysfunction and sustained hyperandrogenism. No consensus guidelines exist regarding the diagnosis and management of PCOS in the pediatric population; however, because the syndrome is a diagnosis of exclusion, the clinical evaluation of girls suspected of having PCOS is aimed at excluding other causes of androgen excess and menstrual dysfunction. For the syndrome's management, emphasis is placed on lifestyle and symptom-directed treatment.
Nutrition and Metabolic Health · Body Weight and Composition
The onset and progression through the various stages of puberty are influenced by a number of factors (Fig. 2). In both animals and humans, the age of puberty appears to be related more to body weight than to chronologic age. Undernutrition and low body fat, or an altered ratio of lean mass to body fat, seem to delay the adolescent spurt and to retard the onset of menarche. According to Frisch, a minimum level of fatness (17% of body weight) is associated with menarche; however, a heavier minimum weight for height, representing an increased amount of body fat (22%), appears necessary for the onset and maintenance of regular menstrual cycles in girls over 16 years of age. This critical amount of body fat implies that a particular body composition, in addition to other environmental and psychosocial factors, is important in triggering and maintaining the pubertal process.