Placental Chronic Inflammatory Histopathology and Fetal Growth in a Cohort with Universal Placental Examination.

Introduction Chronic placental inflammation is a routinely diagnosed group of placental lesions that reflect immunologic dysfunction of the mother, fetus, or both. Methods Complete placental pathology examinations were performed for all term births at New York Presbyterian- Brooklyn Methodist Hospital from January 2010- August 2016. Diagnoses were blinded except to gestational age. CPI lesions were marked as chronic choriodeciduitis, decidual plasma cells, chronic inflammation of basal plate with anchoring villitis, and chronic villitis. Results In this cohort of term pregnancies, 257 (11.6%) males and 218 (9.8%) females had >1 CPI lesions. Chronic villitis was the most common (319 or 14%), with chronic choriodeciduitis, decidual plasma cells, and chronic inflammation of basal plate with anchoring villitis in 94 (4%), 69 (3%) and 170 (8%), respectively. In males, chronic villitis was associated with lower gestational adjusted birthweight and had no association with placental weight. In females, chronic villitis was associated with lower gestational adjusted birthweight, but the effect became nonsignificant after adjustment for placental weight. Discussion In summary, CPI lesions’ incidence and association with birth weight vary by sex. Chronic villitis is associated with lower birthweight in females; this effect is completely mediated by placental weight. Chronic villitis showed a weak direct association of chronic villitis in males, but no association with lower placental weight in males. We suggest that differences between our results and previous publications reflect effects of sampling bias.