Xylitol and the Prevention of Periodontal Disease and Preterm Birth Trial

Inclusion Criteria: * Able to provide informed consent. For those under 18 years of age, an approval will additionally be sought from the parent or guardian * Less than 20 weeks' gestation (by best obstetric estimate) * At least 20 natural teeth * Planning to deliver at one of the health facilities within the XaPPP trial * Receiving antenatal obstetric care at one of the 8 health districts * Willing to chew two pieces of gum thrice daily for 5 minutes after the morning, day and evening meals throughout pregnancy * Willing to attend all study visits * Willing to provide biospecimens (oral, vaginal, placental, breast milk) * Willing to undergo at least two dental exams including oral microbiota sampling at study enrolment \<20 weeks of pregnancy, 28-30 weeks of pregnancy, and 6-8 weeks after giving birth * Willing to have their child undergo follow up through at least 12 months after birth including neurodevelopmental examination(s) * Speaks Chichewa or English All patients who meet inclusion criteria will be approached without regard to sex, race, ethnicity, parents' country of origin, or religious preferences. Exclusion Criteria: * Those who upon screening and enrolment but dislike the taste of the gum and state they will not chew the gum throughout pregnancy * Gravidae with known or suspected non-viable pregnancy (including life threatening congenital anomalies such as cardiac, neurological or others) * Pregnant individual has a life-threatening diagnosis such as cancer requiring treatment during pregnancy * Pregnant women with a known or suspected morbidly adherent placenta (such as placenta accrete, increta and percreta) * Known allergy to xylitol