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Epidemiologic correlates with menstrual cycle length in middle aged women

I Kato1, P Toniolo, K L Koenig

  • 1Nelson Institute of Environmental Medicine and Kaplan Comprehensive Cancer Center, New York University School of Medicine, New York, USA. katoi01@popmail.med.nyu.edu

European Journal of Epidemiology
|December 23, 1999
PubMed

While irregular menstruations have been associated with lower cumulative exposure to the ovarian steroids, shorter regular cycles have been postulated to increase the cumulative exposure. Epidemiological correlates with menstrual patterns were analyzed among 4900 premenopausal women aged 45 or younger from the New York University Women's Health Study. The length of regular menstrual cycles increased with increasing age at menarche, body mass index and parity, but decreased with age, nonwhite racial background and current smoking. The likelihood of irregular cycles increased with increasing age, body mass index and number of cigarettes smoked per day. With adjustment for age, body mass index and number of cigarettes smoked per day, the risk of irregular cycles was marginally positively associated with total fat intake.

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