4 weeks pregnant pregnancy reaction is not yet obvious, will appear similar to the performance of the flu, pregnancy reaction during pregnancy has a lot to do with personal constitution, some of the more sensitive women will show symptoms such as weakness, nausea, vomiting, drowsiness, but the obvious degree of symptoms vary from person to person, there will be the following kinds of reactions: 1, body fatigue, early pregnancy pregnant body will begin to secrete progesterone, can make pregnant women The secretion of progesterone will affect the digestive system of pregnant women, causing constipation and indigestion, and the secretion of human chorionic gonadotropin can cause nausea and vomiting; 4, frequent urination, hormonal changes, uterine The change of hormonal secretion, uterine pressure on the bladder, and increased blood flow to the kidneys can all lead to frequent urination.