Menstruation and biochemical abortion is not easy to distinguish, in the early stages of pregnancy the fertilized egg is not well developed, or without the bed discharged for biochemical abortion, biochemical abortion after vaginal bleeding, this time the abortion of the body is less harmful, so the bleeding is similar to the menstruation, due to the biochemical abortion in the time with menstruation is almost the same, the pregnancy is often overlooked. Menstruation and biochemical abortion to identify the way to monitor ovulation in the 9-10 days of ovulation blood test HCG, able to detect whether the pregnancy, or in the imminent menstruation before the use of pregnancy test paper to do a urine test, if there is a positive indication of pregnancy, the detection of pregnancy soon after the appearance of vaginal bleeding that is, miscarriage. Biochemical abortion is generally due to the sperm and egg quality is not good, the fertilized egg chromosomal abnormalities, obstacles to the implantation of the resulting, it is recommended that the next time before pregnancy to do the relevant examinations, while taking folic acid tablets in advance.