It is recommended that ultrasound examination be performed in early pregnancy to understand the growth and development of the embryo as well as the fetus. According to the advice of the obstetrician, the time of medication and the gestational age are projected, and the impact on the embryo is projected. The main ingredient of Yutin is levonorgestrel, which is a simple progestin, and its contraceptive mechanism is to inhibit ovulation and prevent the implantation of the pregnant egg, increase the viscosity of the cervical mucus and prevent sperm penetration. Although experts point out that inadvertent use of contraceptive pills in early pregnancy has not been found to have adverse effects on the fetus, especially within two weeks of fertilization, and teratogenicity is not obvious, the long-term effects on the fetus remain to be seen. It is important to perform regular maternity examinations during pregnancy, even in the absence of any abnormalities, pregnant women may conceive defective fetuses. Systematic checkups are needed during pregnancy, paying attention to some conditions such as screening for fetal congenital developmental abnormalities.