TY - JOUR
T1 - Female fecundity in highland Papua New Guinea.
AU - Johnson, P. L.
AU - Wood, J. W.
AU - Weinstein, M.
N1 - Funding Information:
We thank Anne Buchanan, Kenneth Campbell, Peter Ellison, and Kenneth Weiss for comments andsuggestions. This research was partly funded by NICHD grant 7 ROI HD20989-O2 and NSF grant BNS-8615248.
PY - 1990
Y1 - 1990
N2 - Demographers often assume that interpopulation variation in birth spacing is attributable primarily to behavioral differences (e.g., in breastfeeding, coital frequency, or contraceptive practice), and that the contribution of physiological factors is negligible. This assumption may be correct, but it should be tested, especially in light of recent evidence that there may be more variation in ovarian function among human populations than was previously believed. In this paper, we apply a stochastic model of the determinants of fecundability (the monthly probability of conception) to endocrinological data collected among the Gainj, a tribal population in highland Papua New Guinea. Based on previous research, the Gainj are known to have age patterns of ovarian function that differ markedly from the Western norms. When account is taken of the late menarche, early menopause, and long ovarian cycles that appear to characterize Gainj women, mean apparent fecundability across the female reproductive span is reduced by about 27 per cent (from 0.316 to 0.235), and the mean waiting time to next apparent conception is increased by just over one month. Thus, despite the fact that Gainj women differ from Western women with respect to reproductive physiology by as much as or more than any other known population, the demographic impact of these differences appears to be slight.
AB - Demographers often assume that interpopulation variation in birth spacing is attributable primarily to behavioral differences (e.g., in breastfeeding, coital frequency, or contraceptive practice), and that the contribution of physiological factors is negligible. This assumption may be correct, but it should be tested, especially in light of recent evidence that there may be more variation in ovarian function among human populations than was previously believed. In this paper, we apply a stochastic model of the determinants of fecundability (the monthly probability of conception) to endocrinological data collected among the Gainj, a tribal population in highland Papua New Guinea. Based on previous research, the Gainj are known to have age patterns of ovarian function that differ markedly from the Western norms. When account is taken of the late menarche, early menopause, and long ovarian cycles that appear to characterize Gainj women, mean apparent fecundability across the female reproductive span is reduced by about 27 per cent (from 0.316 to 0.235), and the mean waiting time to next apparent conception is increased by just over one month. Thus, despite the fact that Gainj women differ from Western women with respect to reproductive physiology by as much as or more than any other known population, the demographic impact of these differences appears to be slight.
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U2 - 10.1080/19485565.1990.9988744
DO - 10.1080/19485565.1990.9988744
M3 - Article
C2 - 2270505
AN - SCOPUS:0025400503
SN - 0037-766X
VL - 37
SP - 26
EP - 43
JO - Social Biology
JF - Social Biology
IS - 1-2
ER -