The composition of contraceptive pills is mainly estrogen and progesterone, which may cause obesity or swelling, gastrointestinal discomfort and menstrual disorders after taking them. 1. Obesity or swelling: because the emergency contraceptive pill is a hormonal drug, containing estrogen and progesterone, progesterone is easy to affect the metabolism, promote tissue growth, easy to cause obesity, estrogen will cause sodium retention in the body to appear swollen phenomenon. 2. Gastrointestinal discomfort: mainly due to the irritation of the gastrointestinal tract caused by contraceptive pills into the gastrointestinal tract caused by gastrointestinal reactions, gastrointestinal discomfort mainly manifested as nausea, vomiting, abdominal pain and other symptoms. 3. Menstrual disorders: contraceptive pills due to its inhibitory, delayed ovulation and inhibit the role of the endometrium, can make the next menstrual period delayed, but also due to the temporary use of temporary medication caused by the one-time temporary elevation of hormone levels in the blood, the decline of withdrawal bleeding occurs, manifested as menstruation in advance. Long-term use of birth control pills may also lead to infertility, if the patient takes birth control pills have adverse reactions, immediately stop the drug and promptly seek medical attention, under the guidance of the doctor to deal with.