Evaluation of salivary flow, pH and buffer capacity in the gestational and postpartum periods: a prospective case-control study

Abstract

Introduction:
There is divergence in the literature about salivary changes taking place during pregnancy. Objective: Evaluating salivary flow, pH and buffer capacity in women during gestational and postpartum periods, as well as comparing these parameters to those of non-pregnant women. Methods: Prospective case-control study conducted with convenience sample comprising pregnant (P) and non-pregnant (NP) women (1 case: 2 controls). Stimulated saliva samples were collected in the morning during pregnancy (20th, 30th and 38th gestational weeks) and after delivery. Data analysis was based on Shapiro-Wilk, Student’s t, Mann-Whitney and Friedman tests (p <0.05). Results: The study assessed 17 pregnant (mean age = 26.1±4.4 years) and 28 non-pregnant women (mean age = 24.4±4.4 years). There was difference in salivary flow (p=0.023) and buffer capacity (p=0.033) between P and NP during the postpartum period, as well as in salivary pH at the 20th (p=0.007) and 30th gestational weeks (p=0.010). Pregnant women did not show changes in salivary flow and pH during pregnancy and after delivery (p> 0.05). However, they recorded increased saliva buffer capacity in the postpartum period (p <0.001). Conclusion: Pregnant women presented lower salivary flow and buffer capacity in the postpartum period, as well as lower salivary pH during pregnancy (20th and 30th gestational weeks), than the group of non-pregnant women. There was no change in salivary flow and pH among pregnant women; however, they presented increased saliva buffer capacity at follow-up time.