How to Cite this Article: Kurosawa K, Masuno M, Kuroki Y. 2012. Trends in occurrence of twin births in Japan. Am J Med Genet Part A 158A:75–77.
Trends in occurrence of twin births in Japan†
Article first published online: 21 NOV 2011
Copyright © 2011 Wiley Periodicals, Inc.
American Journal of Medical Genetics Part A
Volume 158A, Issue 1, pages 75–77, January 2012
How to Cite
Kurosawa, K., Masuno, M. and Kuroki, Y. (2012), Trends in occurrence of twin births in Japan. Am. J. Med. Genet., 158A: 75–77. doi: 10.1002/ajmg.a.34362
- Issue published online: 19 DEC 2011
- Article first published online: 21 NOV 2011
- Manuscript Accepted: 3 OCT 2011
- Manuscript Received: 1 MAY 2011
- Ministry of Health, Labour and Welfare, Japan
- assisted reproductive technology (ART);
- Kanagawa Birth Defects Monitoring Program (KAMP);
The rise in the rate of multiple births since the 1980s is due to the effect of advanced maternal age and increased use of assisted reproductive technology (ART). To determine the trends of prevalence in twin births, we studied the data of a population-based birth defects monitoring system during 26 years in Kanagawa Prefecture, Japan. A total of 15,380 twins from 7,690 deliveries were ascertained from 990,978 births in the Kanagawa Birth Defects Monitoring Program (KAMP) during 1981–2008. From the start of KAMP in 1981, the incidence of twin births had been consistently increasing from 57.0 to 98.6 per 10,000 deliveries until 2003, but after this time, the incidence declined to 78.5 in 2007. While the rate of monozygotic twins has been stable (∼40 per 10,000 deliveries) after 1990, that of dizygotic twins increased from 25.3 to 57.3 per 10,000 deliveries until 2002, and recovered to 40.1 in 2007. These results showed the most recent tendency of twin births and indicated that the single embryo transfer method can provide protection and reduction of perinatal risk caused by multiple births. © 2011 Wiley Periodicals, Inc.