The FDA classifies Unisom as Category B. This means the medication is likely safe because animal reproductive trials haven’t shown any complications. Category B also means there aren’t definitive human trials that prove that the medication is totally safe for use in the first trimester or beyond B级的药也不一定完全安全，几十年前对孕吐安全的药后来也被证明造成胎儿短足。尤其第一孕程要小心。我的ob就没推荐吃药，总之自己的选择吧。 Think about the risks and benefits before taking any pills! Unisom本身副作用也挺大，嗜睡昏沉什么的。
