There is no bibliographical data concerning the role of delayed type hypersensitivity (DTH) (a Th1 type immune response) in reproduction.

The aim of the study was to estimate DTH responses in women with recurrent spontaneous abortions (RSA) or with repeated unsuccessful in vitro fertilizations (IVFs).

One hundred and seventy women with two or more RSA (group A), 38 infertile women having three or more unsuccessful IVFs (group B) and 30 women who had two or more successful gestations and no abortions (group C, controls) were studied. All women were questioned whether they have expressed DTH response (typical question posed was whether they had a skin reaction to fake jewelry).

In group C, 10/30 women (33%) replied positively. Respective ratios in group A and B were higher, but the difference was not statistically significant: in group A, 77/170 (45.3%) were DTH+ (group A1) and 93 (54.7%) DTH- (group A2), whereas in group B, 14/38 (36.8%) were DTH+ and 24 (63.2%) DTH- (groups B1 and B2, respectively). The average rate of miscarriages or unsuccessful IVFs was 2.9, 2.2, 3.3 and 2.7 in groups A1, A2, B1 and B2, respectively. Higher frequency of autoantibodies – mainly antithyroid – were observed in group A2 (NS). Women of group A2 delivered successfully more than twice as compared to A1 group women (22% over 9%, P < 0.02).

The above findings give a primary indication that DTH, having the status of a Th1 type response, possibly constitutes a negatively influencing factor for reproduction.