Decline in sex ratio at birth after Kobe earthquake.
We investigated the possible association between the Kobe earthquake (January 1995) and the sex ratio among live-born infants after the catastrophe. A significant decline in the sex ratio (0.501) of Hyogo Prefecture in October 1995 was observed 9 months after the Kobe earthquake as compared with an expected value of 0.516 in the period from January 1993 to January 1996 (P = 0.04; one-tailed). Simultaneously, a reduction in fertility of approximately 6% was also observed, compared with the month of October 2 years previously. Thus, the acute stress resulting from a great natural catastrophe can be a cause of a low sex ratio at birth 9 months later.
Fukuda Ladies Clinic, Ako, Hyogo, Japan.
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M
Fukuda
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Fukuda
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T
Shimizu
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H
Møller
D004190:Disasters; D005260:Female; D005298:Fertility / Q000502:physiology; D006801:Humans; D007231:Infant, Newborn; D007564:Japan; D008297:Male; D011247:Pregnancy; D012744:Sex Ratio; D013081:Sperm Motility; D013312:Stress, Physiological / Q000503:physiopathology; D013997:Time Factors