Could chewing xylitol gum daily prevent preterm birth?

Chewing xylitol gum daily was associated with a reduced risk of preterm birth, according to a trial conducted in Malawi and presented at SMFM 2022.

“Using xylitol chewing gum as an intervention prior to 20 weeks of pregnancy reduced preterm births, and specifically late preterm births between 34 to 37 weeks,” said study lead author Professor Kjersti Aagaard, Vice Chair of Obstetrics & Gynecology, Texas Children’s and Baylor College of Medicine in Houston, Texas, US.

“This fits with longstanding evidence linking oral health with preterm births,” she added.

The multicentre, open-label, cluster randomized trial involved 10,069 women enrolled at eight health centres in Lilongwe, Malawi, over a 6-year period. The women were enrolled either pre-pregnancy or before 20 weeks gestation. Randomization was done according to centre, with four centres randomized to allocate the intervention (group perinatal and oral health education plus daily xylitol chewing gum use [chewed for 10 minutes once or twice/day throughout pregnancy]) and four to allocate the control (group perinatal and oral health education only). A total of 4,549 women were assigned to the intervention and 5,520 to the control, with outcomes available for 9,670 women at follow-up.

Preterm birth (delivery at <37 weeks gestation) was reduced among women who underwent the intervention compared with the control (12.6 percent vs 16.5 percent; adjusted rate ratio [adjRR], 0.76, 95 percent confidence interval [CI], 0.59–0.99; p=0.045 compared with term [≥37 weeks] births). This translated to a number needed to treat of 26 to prevent one case of preterm birth. [SMFM 2022, abstract LB01]

These findings were primarily attributed to the reduction in late preterm birth (34 to <37 weeks) rate with the intervention vs control (9.9 percent vs 13.5 percent; adjRR, 0.73, 95 percent CI, 0.53–0.99; p=0.049), with no significant difference between groups pertaining to births at <34 weeks (2.7 percent vs 3.0 percent; adjRR, 0.88; p=0.62).

There was also an overall reduction in the number of neonates with birth weight <2,500 g in the intervention compared with the control group (8.9 percent vs 12.9 percent; adjRR, 0.70, 95 percent CI, 0.49–0.99; p=0.046). However, there was no significant difference between groups in terms of birth weight 1,501–2,499 g (8.4 percent vs 12.1 percent; adjRR, 0.69; p=0.056) or ≤1,500 g (0.6 percent vs 0.8 percent; adjRR, 0.68; p=0.22).

“When we analysed by birth weight, instead of estimated gestational age at delivery, we similarly showed a significant improvement in the birth weight with one-third fewer low birth weight babies being born,” noted Aagaard.

The incidence of non-live birth did not differ between the intervention and control groups (0.65 percent vs 1.0 percent; adjRR, 0.66; p=0.46 [compared with neonates who were born alive and survived >28 days]), nor did neonatal demise (0.2 percent vs 0.4 percent; adjRR, 0.43; p=0.057).

A total of 4,220 women were deemed compliant with dental visits. The risk of periodontitis was significantly lower among those in the intervention compared with the control group.

“Studies have shown an association between maternal periodontal disease and preterm birth, but randomized trials of dental scaling/planing in pregnancy have not demonstrated preventative benefit,” said Aagaard and co-authors.

While xylitol chewing gum has been shown to reduce dental caries, its effects on periodontal disease or preterm birth were undetermined, they continued.

“What’s unique about our study is that we used a readily available, inexpensive, and palatable means to reduce the risk of a baby being born too soon or too small. There is some real science behind the choice of xylitol chewing gum to improve oral health, and our novel application to improving birth outcomes is exciting,” Aagaard said.

According to the authors, the trial was conducted in Malawi as its rate of preterm birth is the highest in the world (18.1 per 100 live births). [https://www.who.int/news-room/fact-sheets/detail/preterm-birth, accessed 4 February 2022] Future research is warranted to assess the impact of chewing xylitol gum on birth outcomes in other populations, they said.