title: Antimüllerian hormone, antral follicle count and ovarian volume predict menstrual cycle length in healthy women.
abstract: Although menstrual cycle length is one of the main concerns of women and may have important health consequences, little is known about its predictors. The aim of this study was to identify predictors of menstrual cycle length variability in healthy women.
  
  
  
  Prospective cross-sectional study.
  
  
  
  Two hundred healthy women aged 21-45.
  
  
  
  A questionnaire was administered to determine lifestyle factors. Ovarian parameters, metabolic parameters, pituitary hormones, sex steroids and antimüllerian hormone (AMH) were measured.
  
  
  
  Women with long (≥35 days) and normal (25-34 days) menstrual cycles had >5-fold and >2-fold higher serum AMH levels, respectively, compared to those with short cycles (<25 days). Menstrual cycle length was associated with age but not lifestyle factors. Only one factor group (AMH, antral follicle count [AFC], ovarian volume, testosterone and LH) was significantly associated with menstrual cycle length. Within this factor group, only the ovarian parameters (AMH, AFC, ovarian volume) predicted menstrual cycle length. Each SD increase in AMH (32·9 pmol/l) and ovarian volume (2·29 cm(3) ) was associated with 2·80-fold (95% CI: 1·67-4·69) and 1·62-fold (95% CI: 1·08-2·43) increased risks, respectively, for longer menstrual cycles.
  
  
  
  AMH, AFC and ovarian volume are positively associated with menstrual cycle length in healthy women. Our identification of AMH as an independent predictor of menstrual cycle length puts forth a new notion of utilizing menstrual cycle length to predict possible AMH-dependent/-associated outcomes. In addition, this novel relationship may facilitate the interpretation of AMH levels and its clinico-pathological significance across different centres.
authors.affiliation: Department of Obstetrics & Gynecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore city, Singapore.
authors.forename: Ruoyan
authors.initials: R
authors.lastname: Zhu
authors.affiliation: Department of Obstetrics & Gynecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore city, Singapore.
authors.forename: Bao Hui
authors.initials: BH
authors.lastname: Lee
authors.affiliation: Department of Obstetrics & Gynecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore city, Singapore.
authors.forename: Zhongwei
authors.initials: Z
authors.lastname: Huang
authors.affiliation: Department of Obstetrics & Gynecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore city, Singapore.
authors.forename: Inthrani Raja
authors.initials: IR
authors.lastname: Indran
authors.affiliation: Department of Obstetrics & Gynecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore city, Singapore.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.affiliation: Biostatistics Unit, Yong Loo Lin School of Medicine, National University of Singapore, Singapore city, Singapore.
authors.forename: Liang
authors.initials: L
authors.lastname: Shen
authors.affiliation: Departments of Pediatrics and Epidemiology, Biostatistics and Occupational Health, McGill University Faculty of Medicine, Montreal, Canada.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Kramer
authors.affiliation: Department of Obstetrics & Gynecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore city, Singapore.
authors.forename: Eu-Leong
authors.initials: EL
authors.lastname: Yong
mesh_terms: D000328:Adult; D000367:Age Factors; D054304:Anti-Mullerian Hormone / Q000097:blood*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007986:Luteinizing Hormone / Q000097:blood; D008597:Menstrual Cycle / Q000502:physiology*; D008875:Middle Aged; D009929:Organ Size; D006080:Ovarian Follicle / Q000502:physiology*; D010053:Ovary / Q000502:physiology; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D013739:Testosterone / Q000097:blood; D013997:Time Factors; D055815:Young Adult
chemical_list: D013739:Testosterone; D054304:Anti-Mullerian Hormone; D007986:Luteinizing Hormone