Can you get pregnant if you have negative blocking antibodies?

In general, it is possible to become pregnant with negative blocking antibodies, but the probability of pregnancy is relatively low, as negative blocking antibodies in women may lead to habitual miscarriage. The specific analysis is as follows:

Blocking antibodies refer to a specific IgG antibody present in the serum of pregnant women that targets their partner's lymphocytes. These antibodies can block the cytotoxic effects of a woman's lymphocytes on trophoblasts and prevent her immune system from attacking the embryo. If blocking antibodies are negative, it indicates a deficiency of these protective antibodies in the woman’s body. As a result, the embryo does not receive adequate protection after conception and may be rejected, which is unfavorable for normal embryonic growth and development. Although pregnancy can still occur under such conditions, the chances are lower, and there is an increased risk of complications such as habitual miscarriage or fetal arrest. Therefore, women with negative blocking antibodies who wish to conceive should actively seek treatment. Active immunotherapy is commonly recommended—typically using white blood cells from the spouse. This treatment usually helps convert the blocking antibody test to positive, restoring antibody levels to normal, thereby enabling subsequent pregnancy with a reduced risk of habitual miscarriage.

Patients are advised to seek timely medical care when experiencing any discomfort and to undergo standardized treatment under the guidance of a physician, which will aid in recovery.