Early biochemical pregnancy test strips can be detected, but will not appear strong positive, biochemical pregnancy means that the fertilized egg failed to bed will be discharged with menstruation. Early biochemical pregnancy with early pregnancy test strips should be weakly positive, because the combination of egg and sperm 7 days before the secretion of chorionic gonadotropin, and then 7 days before you can use the test strips to test positive or not. Therefore, a positive test strip can be taken after 14 days of ovulation, and the color of the test line will gradually deepen to determine whether the pregnancy is biochemical phenomenon. The test should be positive in the early days after fertilization, and may be negative if the pregnancy has bled for a longer period of time and symptoms such as vaginal bleeding have already appeared.