Journal Article

Factors Affecting Menstrual Cycle Characteristics

Yan Liu, Ellen B. Gold, Bill L. Lasley and Wesley O. Johnson

in American Journal of Epidemiology

Published on behalf of Johns Hopkins Bloomberg School of Public Health

Volume 160, issue 2, pages 131-140
Published in print July 2004 | ISSN: 0002-9262
Published online July 2004 | e-ISSN: 1476-6256 | DOI:
Factors Affecting Menstrual Cycle Characteristics

Show Summary Details


This 1989–1991 study in California and Utah used daily urinary metabolites of estrogen and progesterone and computer algorithms to assess ovulatory status and day of ovulation. The authors examined the associations of risk factors with menstrual cycle characteristics for 309 working women aged 20–44 years who collected a median of five cycles each of daily urine samples. Linear mixed models were used to assess continuous menstrual outcomes. Compared with women less than age 35 years, women aged 35 years or older had a significantly decreased (–0.94 days, 95% confidence interval: –1.83, –0.05) adjusted mean cycle length. Age modified the effects of smoking, physical activity, ethnicity, and alcohol consumption on mean follicular phase length. Asian women had a significantly longer (1.65 days, 95% confidence interval: 0.54, 2.76) adjusted mean cycle length compared with Caucasian women. Compared with women who did not consume alcoholic drinks, women who did had a significantly shorter (–1.26 days, 95% confidence interval: –2.21, –0.31) adjusted mean cycle length. Mean cycle and phase lengths were significantly associated with length of the prior luteal phase. These results indicate that potentially modifiable risk factors, as well as immutable host factors, are associated with menstrual cycle characteristics that may in turn be related to subsequent disease risk.

Keywords: follicular phase; hormones; life style; linear models, statistical; luteal phase; menstrual cycle; urine; Abbreviations: AOR, adjusted odds ratio; BMI, body mass index; CI, confidence interval; FSH, follicle-stimulating hormone.

Journal Article.  6737 words.  Illustrated.

Subjects: Public Health and Epidemiology

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.