About one in three or four pregnancies ends with the loss of the fetus in what's called a miscarriage, or spontaneous abortion. The majority of miscarriages occur during the earliest stages―the first trimester, or 13 weeks of pregnancy. In fact, many women may not even realize they were pregnant. 일부 유산은 "화학적 유산"에서 나오는데, 이는 긍정적인 검..