羊膜腔穿刺用于产前诊断，操作应进行的时 间是（  ）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='25965' and id < 2177780 and id<>'2177780' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='25965' and id > 2177780 and id<>'2177780' order by id asc limit 5