Pre-eclampsia--a state of mother-fetus immune imbalance.

Serial lymphocyte counts and function tests were done during and after pre-eclamptic pregnancies, and in the offspring. Compared with normal pregnancies, pre-eclamptic pregnancies were associated with lower B-lymphocyte counts in the fathers; lower T-lymphocyte count, lower B-lymphocyte count, and impaired T-lymphocyte function in mothers; a low response in mixed lymphocyte culture (MLC) tests between the mother and father; and an increased B-cell count in the children. Follow-up of one pre-eclamptic woman throughout pregnancy showed important immune changes at the beginning of the second trimester. These findings suggest that pre-eclampsia is caused by a combination of maternal and paternal hyporesponsiveness together with fetal hyperresponsiveness.