Twin pregnancy can be initially considered when a high HCG level is detected in a blood test at around 40 days of early pregnancy. Twin pregnancy can be diagnosed on the 50th day of pregnancy when ultrasound examination reveals two gestational sacs in the uterine cavity. When a woman is pregnant with twins, the uterus enlarges earlier during early pregnancy than in a single pregnancy, and the abdomen may swell significantly. Usually, pregnancy with twins can be clearly diagnosed by ultrasound observation of intrauterine gestational sacs at about 6 weeks of pregnancy, when two gestational sacs can be observed in the uterine cavity. In addition, at around 7-8 weeks of pregnancy, ultrasound can not only find two gestational sacs, but also can see two fetal buds and fetal heartbeat. At the same time, the chorionic gonadotropin level in the blood is significantly higher than that of a single pregnancy, and after 13 weeks, the two embryos can be clearly visualized, including the spine, trunk, and limbs. In addition, since women pregnant with twins often experience severe vomiting, they need to pay attention to increasing nutrition to ensure the normal development of the embryos. At the same time, after pregnancy, pay attention to proper rest, regular life, avoid cold and flu and other conditions.