共 22 条
[2]
[Anonymous], 2009, NATL VITAL STAT REP
[3]
Centers for Disease Control and Prevention (US), 2009, PRAMS MOD PROT 2009
[4]
Centers for Disease Control and Prevention (US)
[5]
American Society for Reproductive Medicine
[6]
Society for Assisted Reproductive Technology, 2007, 2005 ASS REPR TECHN
[8]
Perinatal outcome of singletons and twins after assisted conception: a systematic review of controlled studies
[J].
BRITISH MEDICAL JOURNAL,
2004, 328 (7434)
:261-264B

