Miscarriage

In China, the termination of pregnancy before 28 weeks of gestation, with a fetal weight of less than 1,000 grams, is defined as abortion. According to the different stages of occurrence, it can be divided into: Early abortion: Occurs before 12 weeks of gestation. Late abortion: Occurs after 12 weeks of gestation. According to the different causes of occurrence, it can be divided into: Spontaneous abortion: The embryo or fetus develops in the uterus for too short a time to continue the pregnancy. Induced abortion: Termination of pregnancy by artificial means due to unintended pregnancy or medical reasons. Typically, after embryo implantation, about 3/10 of pregnancies result in spontaneous abortion, with the vast majority (about 80%) being early abortions. Among early abortions, more than half are cryptic abortions, meaning they occur before the menstrual period. The main symptoms are vaginal bleeding and abdominal pain.