双胎妊娠的发生与胎次、孕妇年龄、遗传等多因素有关。近年来医源性原因促排卵药物的应用使双胎、多胎发生率有上升的趋势,高达20% ~ 40%[1]。双胎妊娠属于高危妊娠,母婴并发症增多,孕妇早产发生率、围产儿死亡率、新生儿窒息发生率升高,应给予足够重视[2,3]。本文对1999年 The occurrence of twin pregnancy and fetal parity, pregnant women age, genetic and other factors. In recent years, iatrogenic causes of ovulation induction drug application of twins, multiple births have a rising trend, up to 20% to 40% [1]. Twin pregnancies are high-risk pregnancies, maternal and child complications increased, the incidence of preterm births in pregnant women, perinatal mortality, neonatal asphyxia increased incidence should be given enough attention [2,3]. This article on 1999