Long Ovarian Cycles in Women of Highland New Guinea

Document Type

Article

Authors

Patricia L. Johnson, University of Wisconsin
James W. Wood, University of Wisconsin
Kenneth L. Campbell, University of Massachusetts
Ila A. Maslar, Oregon Regional Primate Research Center

Abstract

Self-reported menstrual diaries were collected over a ten-week period from 36 women of a small tribal isolate in highland New Guinea known as the Gainj. All 36 subjects were healthy and were known from their serum hormone levels to be cycling; none was currently married, lactating or using any form of contraception. A survival analysis of the menstrual data indicates that the median cycle length of these women is 36 days, approximately 40% longer than the median estimated for a sample of U.S. women matched with the Gainj subjects for gynecological age. The difference between the U.S. and Gainj women is highly significant (logrank test statistic = 34.8, p < 0.0001). It thus appears that inter-population variation in human ovarian cycle length may be substantial.

Recommended Citation

Johnson, Patricia L.; Wood, James W.; Campbell, Kenneth L.; and Maslar, Ila A. (1987) "Long Ovarian Cycles in Women of Highland New Guinea," Human Biology: Vol. 59: Iss. 5, Article 11.
Available at: https://digitalcommons.wayne.edu/humbiol/vol59/iss5/11