The uncertain safety and effectiveness of test drugs and medical instruments in clinical trials might pose risks to the subjects, and pregnancy events emerging in clinical trials will increase the risks. At present, most of pregnancy events are recorded and reported as an adverse event, but due to their particularity, it is inappropriate to record and handle them with other adverse events. Pregnancy event closely is related to the interests of the sub-jects and the risk it might face, besides, it is also related to the interest and risk of their spouses and offspring. In order to handle pregnancy event, this paper elaborated responsibilities of researchers, sponsors and subjects accord-ing to the purpose of trials in three aspects, including experiment design, informed consent, and test expand, so that the interest of the subjects could get better protection.