3Luke B, Minogue J, Witte FR, et al. The ideal twin pregnancy: patterns of weight gain, disordancy and length of gestation [J]. Am J Obstct Ggnecol, 1993, 169(3): 588-597.
4Ballabh P, Kumari J, Alkouatly HB, etal. Neonatal outcome of triplet versus twin and singleton pregnancies: amatched case control study[J]. Eur J Obstet Gyneeol Reprod Biol, 2003, 107(1): 28-36.
5Lantz ME, Chez RA, aodriguez A, et al. Maternal weight gain patterns and birth weight outcome in twin gestation[J].Obstet Gyneeol, 1996, 87(4): 551-556.
6Chavez MR, Ananth CV, Smulian JC, et al. Fetal transcerebellar diameter measurement with particular empbasis in the third trimester: a reliable predictor of gestational age[J]. Am J Obstet Gynecol, 2004, 191(3) : 979-984.
7Goldstein I, Reece EA, Pilu G, et al. Cerebellar measurements with ultrasonography in the evaluation of fetal growth and development [J]. Am J Obstet Gynecol, 1987, 156 ( 5 ): 1065-1069.
8Chavez MR. Ananth CV. Kaminsky LM, et al. Fetal transeerebellar diameter measurement for prediction of gestational age in twins [ J ]. Am J Obstet C-ynecol, 2006, 195(6): 1596-1600.