Macourt D C, Stewart P, Zaki M
Aust N Z J Obstet Gynaecol. 1982 Feb;22(1):25-8. doi: 10.1111/j.1479-828x.1982.tb01393.x.
1,000 multiple births were examined in relation to maternal exposure to an oral contraceptive before conception. There was a significantly higher rate of monozygotic twinning among pregnancies which took place within 6 months of cessation of the contraceptive. In the monozygotic group there was a significant increase in the incidence of congenital abnormalities (P less than 0.01) when conception occurred within 3 months of cessation of the contraceptive.
对1000例多胎妊娠进行了研究，以探讨受孕前母亲使用口服避孕药的情况。在停用避孕药后6个月内怀孕的孕妇中，单卵双胎的发生率显著更高。在单卵双胎组中，当受孕发生在停用避孕药后3个月内时，先天性异常的发生率显著增加（P小于0.01）。
