第一次：孕12 -14周之间可以做一次彩超，主要目的是核准妊娠时间，排除胚胎发育和停经时间不符的情况，修正预产期。

For the first time: 12-14 weeks pregnant between can do a exceeds, main purpose is to approve pregnancy time, eliminate embryonic development and menopause, fixed time discrepancies due date.

youdao

第一次：孕12 -14周之间可以做一次彩超，主要目的是核准妊娠时间，排除胚胎发育和停经时间不符的情况，修正预产期。

For the first time: 12-14 weeks pregnant between can do a exceeds, main purpose is to approve pregnancy time, eliminate embryonic development and menopause, fixed time discrepancies due date.

youdao