In Nepal, investigators are conducting a cohort study to estimate the relationship between signs of periodontal disease in pregnant women and preterm delivery. Within that cohort study, investigators plan to conduct an individually randomized trial of the acceptability and effect chlorhexidine, cetylpyridinium chloride, and salt water oral rinses on gingival crevicular fluid and plaque during pregnancy. Women for this pilot trial will be chosen from a subset of the area currently engaged in the larger cohort study, to simplify logistics. The pilot trial will have four arms (three oral rinse arms, and one control group).

• Arm 1: Twice daily oral rinse containing chlorhexidine 0.12% w/v (n=25 women with periodontitis
• Arm 2: Twice daily oral rinse with cetylpyridinium chloride (n=50; 25 women with/without periodontitis)
• Arm 3: Twice daily oral rinse with salt and water (n=50: 25 women with/without periodontitis)
• Arm 4: No oral rinse (n=50)

To select and enroll these 175 participants, data collectors will use the information they collected during an oral health clinical examination conducted at the time of enrollment into the broader cohort study; this information will be used to classify women by signs of periodontitis.

Those selected through this above process will be read an additional consent form; those agreeing to participate will be provided with a supply of their assigned rinse (and instructions on its use and handling/storage), or no rinse. Those in the three rinse groups will be asked to use the provided rinse twice per day after brushing and to save the empty bottles for collection by the health care worker. At the end of this first visit, women will additionally provide a venous blood sample to measure systemic inflammation markers and fluoride.

Women receiving the rinse will be visited by study workers periodically to provide more oral rinse and check on their adherence to the rinse. All 175 women will be visited after 12 weeks to undergo a second oral health clinical examination and provide a second set of gingival crevicular fluid and plaque samples, to allow for evaluation of the effect of each of the oral rinses as compared to the normal physiological changes in gingival inflammation and biofilm composition during the course of pregnancy.

At this final visit, the women in the three rinse arms will also answer a short questionnaire to gather feedback on acceptability and adherence to the oral rinse.

Inclusion Criteria:

• Pregnant
• <26 weeks gestation at enrollment
• Enrolled in the broader cohort study

Exclusion Criteria:

• Already previously enrolled
• Not Pregnant