4Koivurova S, Hartikainen AL, Gissler M, et al. Neonatal outcome and congenital malformations in children born after in vitro fertilization[J]. Hum Reprod, 2002, 17(5):1 391-1 398.
5Boulot P, Emiliani S, Zhou CQ, et al. Multifetal reduction of triplets to twins: a prospective companison of prenancy outcome[J]. Reprod, 2001, 15(7): 1 619- 1 623.
6Aafke PA, Audrey A, Jolande A. SET irrespective of the availability of a good-quality embryo in the first cycle only is not effective in reducing overall twin pregnancy rates [J ]. Human Reproduction, 2007, 22 (6): 1 669-1 674.
7Evans M I,Britt DW. Fetal reduction[J]. Sem in Perinatol,2005,29(5) :321.
