Cell-Mediated Immune Mechanisms in Recurrent Spontaneous Abortion. In: Talwar GP, editor. Contraception Research for Today and the Nineties. New York: Springer; 1988. pp. 171-80. [DOI: 10.1007/978-1-4612-3746-4_16]

Maternal anti-placental cell-mediated reactivity and spontaneous abortions

PROBLEM

Does Th1/Th2 balance determine pregnancy outcome, and if so, what determines Th1/Th2 balance in pregnancy?

METHOD

Review and synthesis of existing data.

RESULTS

A bias toward Th1 is strongly correlated with pregnancy failure in mice and humans. Pregnancy usually shifts the balance toward Th2 and placental factors/progesterone and progesterone-stimulated CD8+ T cell production of suppressor factor; TGFbeta2 and IL4/10 may be responsible. The bias toward a Th1 response may result from intracellular parasitic infection and other as yet undefined factors.

CONCLUSION

The Th1/Th2 balance thesis appears to be valid.

Predictors of pregnancy success in repeated miscarriage

Factors that may have a bearing on subsequent pregnancy success or failure in patients with recurrent abortion were examined in 165 women with a history of three or more consecutive miscarriages in the first trimester. The overall success rate was 67.9%. Factors that were found to correlate significantly with success rate were length of abortion history, total number of abortions, interval from last miscarriage to present pregnancy, and whether there was any degree of subfertility. Logistic regression analysis showed that the abortion x years index and maternal age accounted for all the variation observed in our data. Where all other known causes of abortions are excluded, recurrent aborters can be subdivided into two populations--namely, those with a relatively good prognosis characterized by a short abortion history and absence of subfertility problems, compared to those with a poor prognosis namely those with a long abortion history or presence of subfertility problems. These data clearly demonstrate major differences in success rates in women depending on the number of abortions and the length of abortion history (abortion x year index), particularly in women over the age of 30 years.