229-236Pregnancy is not as successful as one might think; it can be compromised by several complications such as recurrent
spontaneous miscarriage, pre-term delivery, pre-eclampsia etc. Much attention has been paid to the possibility of the
maternal immune system mediating deleterious effects on pregnancy. Research conducted during the last two decades has
shed much light on cell-mediated immunologic effectors that might underlie these pregnancy complications. Of particular
interest are the effects that pro-inflammatory and anti-inflammatory cytokines have on the foetus and placenta, and thus on
the success and failure of pregnancy. This review presents evidences that certain cytokine profiles are associated with
recurrent miscarriage and pre-term delivery and discusses possible pathways of effector function of cytokines in pregnancy
loss and the redirection of cytokine profiles from one that is antagonistic to pregnancy towards one that is conducive to the
success of pregnancy. Among the promising agents for the modulation of the Th1/Th2 balance are progestogens like
progesterone and dydrogesterone; this review also discusses recent evidence that progestogens are capable of modulating
cytokine production patterns in pregnancy loss