Onset of ovulation after menarche in girls: a longitudinal study.
ABSTRACT Hypothalamic-pituitary axis maturity has been believed to be the rate-limiting step in the development of ovulatory menstrual cycles. We hypothesized that, given current nutritional conditions, hypothalamic-pituitary axis maturation would be relatively rapid in menarcheal girls.
Daily urine and menstrual records were collected for 2 yr each from 10 girls aged 11-13 yr at study entry. Urinary excretion of LH, FSH, estradiol (E1c), and progesterone (Pdg) metabolites was measured using established ELISAs. An objective algorithm detected rises of LH, FSH, E1c, and Pdg consistent with follicular maturation and/or ovulation.
Nine of 10 girls enrolled into the study experienced the onset of menarche prior to or during the 2-yr collection period. LH and FSH surges, as well as small amplitude Pdg increments, were observed prior to menarche. Regular, ovulatory-appearing cycles with LH surges and gradually increasing and more sustained Pdg rises were observed over time after menarche, although duration of Pdg elevations remained shorter than in adult women (8.9 +/- 1.0 vs. 12.1 +/- 0.8 d, P = 0.043). E1c levels leading to LH/FSH surges were lower in perimenarcheal girls than adult controls, and bleeding episodes did not uniformly correlate with hormone patterns. Progressive increases in FSH and Pdg, but not LH or E1c, were observed in association with menarche.
Mature hormone patterns are established within several months of and even prior to menarche in normal-weight perimenarcheal girls. Factors determining menstrual bleeding in perimenarcheal girls may not be solely dependent on reproductive hormones or the neuroendocrine axis.
Article: Relationship of the menstrual cycle pattern in 14-17 year old old adolescents with gynaecological age, body mass index and historical parameters.[show abstract] [hide abstract]
ABSTRACT: In a cross-sectional population-based study the association between the menstrual pattern in ninth grade schoolgirls and calendar age, gynaecological age, body mass index (BMI) and historical parameters was investigated. The survey was held in a combined urban and rural region, south of Amsterdam. A total of 2480 adolescents, mean age 15.3 +/- 0.6 (SD) years, answered a questionnaire: response 92%. The menstrual cycle patterns were categorized to regular menstrual cycles (RMC), irregular menstrual cycles (IMC), oligomenorrhoea, polymenorrhoea, pre-menarche, <6 months after menarche, and oral contraceptive use. Gynaecological age was strongly associated with the prevalence of IMC but only weakly with the prevalence of oligomenorrhoea. In a logistic regression analysis gynaecological age, subjective acne and intellectual performance were independently associated with oligomenorrhoea. Gynaecological age, low BMI, chronic non-specific lung disease (CNSLD) or allergic disease, stress and strain, weight loss of >5 kg were independently associated with IMC. More than 8 h sports per week was associated with not having experienced menarche in the ninth grade but not with menstrual cycle disturbances. The association between CNSLD or allergic disease and IMC has not previously been described. The associations between weight loss, low body weight, stress, physical exercise or signs of hyperandrogenism and menstrual cycle patterns in adolescents are weak when studied on a population basis. The value of these parameters to explain abnormal menstrual cycle patterns is limited.Human Reproduction 09/1998; 13(8):2252-60. · 4.47 Impact Factor
Journal of the American Chemical Society 08/1970; 92(13):3910-4. · 9.91 Impact Factor