Background: Estrogen regulates the cellular functions of several tissues that may disturb the host response against bacteria. The present aim is to evaluate the contribution of estrogen to the severity of gingival inflammation during pregnancy.
Methods: Salivary estrogen levels from 30 pregnant and 24 non-pregnant females were related to their periodontal health parameters, including visible plaque index (VPI) and bleeding on probing (BOP) from six sites per tooth. The pregnant group was examined three times during pregnancy and twice during postpartum, and the non-pregnant group was examined three times, once per subsequent month.
Results: Salivary estrogen levels increased significantly during the second (P <0.01) and third (P <0.05) trimesters. In both participant groups, BOP scores correlated significantly with VPI scores (r = 0.498 to 0.870) but not with estrogen levels. In all trimesters and postpartum, the individuals with both high estrogen and high VPI levels had the highest frequency of pregnancy gingivitis. During the second and third trimesters, simultaneously enhanced estrogen levels and VPI scores brought an additional risk of developing gingivitis compared with a high VPI score alone.
Conclusion: The present findings suggest that, during pregnancy, the estrogen level determines the magnitude of gingival inflammation developed against microbial plaque at the gingival margin.