Westergaard T, Wohlfahrt J, Aaby P, Melbye M
Afdeling for Epidemiologisk Forskning, Statens Serum Institut, København, .
Ugeskr Laeger. 1998 Sep 28;160(40):5794-7.
The objective was to study trends in national rates of multiple pregnancies that were not explained by changes in maternal age and parity. Information on childbirths to Danish-born women were obtained from national registers. The national incidence of multiple pregnancies increased 1.7-fold during 1980-1994, the increase primarily in 1989-1994 and almost exclusively in primiparous women > or = 30 years, for whom the adjusted population-based twinning rate increased 2.7-fold and the triplet rate 9.1-fold. The proportion of multiple births among infant deaths in primiparous women > or = 30 years increased from 11.5% to 26.9%. In conclusion, the marked increase in the rate of multiple pregnancies, which in particular was observed during the 1990s and in primiparous women > or = 30 years, could not be explained by changes in maternal age or parity. Fertility-enhancing treatments are believed to have caused this increase.
目的是研究未因产妇年龄和胎次变化而得到解释的国家多胎妊娠率趋势。丹麦出生女性的分娩信息来自国家登记处。1980 - 1994年期间，国家多胎妊娠发生率增加了1.7倍，增长主要发生在1989 - 1994年，且几乎完全发生在年龄≥30岁的初产妇中，她们基于人群调整后的双胎率增加了2.7倍，三胎率增加了9.1倍。年龄≥30岁初产妇的婴儿死亡中多胎分娩的比例从11.5%增至26.9%。总之，多胎妊娠率的显著增加，尤其是在20世纪90年代以及年龄≥30岁的初产妇中观察到的这种增加，无法用产妇年龄或胎次的变化来解释。据信是生育增强治疗导致了这种增加。
