Why does pre-eclampsia occur?
There appears to be an ill-defined genetic predisposition to pre-eclampsia, with some studies suggesting an autosomal recessive inheritance. However, discordance for pre-eclampsia among monozygotic twins questions some of the genetic postulates. Paternal influence on fetomaternal genetic mismatch is important, and being born of a pre-eclamptic pregnancy increases the likelihood for males of fathering an infant whose gestation will also be complicated by pre-eclampsia. Immune theories abound, largely arising from epidemiological observations that pre-eclampsia is more common in a first pregnancy, and that changing partners for a subsequent pregnancy increases the risk of pre-eclampsia in women with a previous normal pregnancy and decreases the risk in women with previous pre-eclampsia.1 Prolonged sexual cohabitation before pregnancy appears to protect against pre-eclampsia, the implication being that this allows development of greater maternal “tolerance” to paternal antigens present in
