In the early stages of pregnancy, it is normal for pregnant women to experience drowsiness. After pregnancy, the levels of estrogen, progesterone and chorionic gonadotropin will increase in the pregnant woman’s body. Early pregnancy reactions include morning sickness, nausea, drowsiness, fatigue, acid reflux and aversion to oil, which are collectively referred to as early pregnancy reactions. Early pregnancy reactions are mainly related to the increase of chorionic gonadotropin level in pregnant women’s body after pregnancy. Generally, after the third month of pregnancy, i.e. 12 weeks, the chorionic gonadotropin level will decrease, and the early pregnancy reactions of pregnant women will be significantly reduced or disappear at this time. Therefore, it is a normal physiological phenomenon for pregnant women to be drowsy during early pregnancy, and the early pregnancy reaction will be reduced or disappeared after 3 months.