Whether a weak positive cytomegalovirus IGM in pregnant women is serious or not also depends on the results of the IGG antibody test. If a woman has a positive blood test for cytomegalovirus IGM antibodies during pregnancy, she needs to look at the results of the IGG anti-antibody. 1. If the cytomegalovirus IGG anti-antibody is negative, it can be re-tested after a period of time. If the re-test becomes positive, then this situation indicates the initial infection of cytomegalovirus, which may lead to abnormal development of the fetus. This situation is more serious, and requires timely treatment with antiviral drugs, regular pregnancy tests, and termination of pregnancy if necessary. 2. If the cytomegalovirus IGG antibody is negative, and remains negative when retested after a period of time, it means that the weakly positive cytomegalovirus IGM antibody may be a false positive, which means that there is no cytomegalovirus infection. If this is the case, of course, it is not serious and will not lead to fetal malformation. It is recommended that you have regular checkups during pregnancy and follow up with your doctor.