羊膜腔穿刺用于产前诊断应在妊娠何时 进行（  ）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='25967' and id < 2178046 and id<>'2178046' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='25967' and id > 2178046 and id<>'2178046' order by id asc limit 5