The necessity of the ABO test for preconception depends mainly on the blood type of the mother-to-be. If the mother has O blood type, it is still recommended to have an antibody titer done before pregnancy; in addition, one such test should be done after pregnancy, at about 16 weeks and 24 weeks. In fact, the probability of ABO hemolysis is very low, so even if the mother has O blood type, there is no need to panic too much, as long as the pregnancy test is done properly. If the titer is indeed found to be higher, the obstetrician will also give some guidance according to the situation, such as eating some Injury Yellow, and will also do a good job of preventing hemolysis in the newborn. So don’t panic if you have these problems, as long as you do your regular obstetric checkups, the incidence of high-risk diseases is still relatively low.