Article contents
Alternate Changes in Birth Seasonality of Twins During 1971–1984 in Japan
Published online by Cambridge University Press: 01 August 2014
Abstract
Birth dates of 1,536 twin-pairs in 1971-1984 were collected from the members of an association of twins' mothers. The seasonal variation of twinning changed every 2-4 years. Years when twinning rate was higher in the summer-fall season (1971-72, 1976-77, 1982-84) and those when a peak of the rate was not observed (1973-75, 1978-81) appeared alternately. In years with a summer-fall peak, the elevation of twinning in the summer-fall season was detected consistently in both like- and unlike-sexed and in both MZ and DZ twin groups. The twinning seasonality in these years, however, was not evident in twin births of mothers who were born in May-July. These results suggest the possibility that seasonal factors which influence the twinning rate be not multiple-ovulation-inducing but probably abortion-inducing factors and most likely seasonally epidemic microbes.
- Type
- Research Article
- Information
- Acta geneticae medicae et gemellologiae: twin research , Volume 36 , Issue 3 , July 1987 , pp. 373 - 380
- Copyright
- Copyright © The International Society for Twin Studies 1987
References
REFERENCES
- 5
- Cited by