Many moms-to-be who have taken medications or other before they knew they were pregnant get worried and nervous about whether they can continue to get pregnant. Here would like to tell you: The toxic effect of the drug has a lot to do with the gestational age when you take the drug. First, the effect of the medication is not significant in the pre-implantation period (that is, within 2 weeks after fertilization, as we said). However, after fertilization and up to about 12 weeks of pregnancy (this is the stage of formation and development of fetal organs) is the main period in which drugs cause malformations. Third, from the 12th week of pregnancy until delivery, the fetal organs have been formed, resulting in malformations will be significantly weakened, but the nervous system has been developing throughout the pregnancy, so the effect of drugs on the nervous system has always been there.