LEUKOCYTE SUBPOPULATIONS IN THE HUMAN UTERINE CERVICAL STROMA AT EARLY AND TERM PREGNANCY

Leukocyte subsets were detected by immunohistochemical methods in cerv ical tissue in either the first trimester or at term pregnancy, In tis sue obtained during first trimester lower total numbers of leukocytes were observed in comparison with late pregnancy (2.7 cells/0.04 mm(2) versus 5.5 cells/0.04 mm(2)). The major subgroup of leukocytes present in early pregnancy was T-lymphocytes, The majority of these cells mer e of the suppressor/cytotoxic subtype, Neutrophils were present at abo ut 1/5th of the density of T-lymphocytes, Very few macrophages were ob served at this stage, At term pregnancy, neutrophils were present in s ignificantly higher numbers than during first trimester with no differ ence between tissue obtained before or during active labour, Macrophag es mere present at about 10-fold higher density than during early preg nancy, In conclusion, tissue-bound leukocytes are present in the human cervix at a higher density in late pregnancy compared to first trimes ter, The increased densities of neutrophils and macrophages at this st age indicate a role for these cells during cervical ripening.