A randomized controlled trial of pre-conception treatment for periodontal disease to improve periodontal status during pregnancy and birth outcomes.

Background: Evidence has suggested that periodontal disease is associated with an increased risk of various adverse pregnancy and birth outcomes. However, several large clinical randomized controlled trials failed to demonstrate periodontal therapy during pregnancy reduced the incidence of adverse pregnancy and birth outcomes. It has been suggested that the pre-conception period may be an optimal period for periodontal disease treatment rather than during pregnancy. To date, no randomized controlled trial (RCT) has examined if treating periodontal disease before pregnancy reduces adverse birth outcomes. This study aims to examine if the pre-conception treatment of periodontal disease will lead to improved periodontal status during late pregnancy and subsequent birth outcomes.

Methods/design: A sample of 470 (235 in each arm of the study) pre-conception women who plan to conceive within one year and with periodontal disease will be recruited for the study. All participants will be randomly allocated to the intervention or control group. The intervention group will receive free therapy including dental scaling and root planning (the standard therapy), supragingival prophylaxis, and oral hygiene education. The control group will only receive supragingival prophylaxis and oral hygiene education. Women will be followed throughout their pregnancy and then to childbirth. The main outcomes include periodontal disease status in late pregnancy and birth outcomes measured such as mean birth weight (grams), and mean gestational age (weeks). Periodontal disease will be diagnosed through a dental examination by measuring probing depth, clinical attachment loss and percentage of bleeding on probing (BOP) between gestational age of 32 and 36 weeks. Local and systemic inflammatory mediators are also included as main outcomes.

Discussion: This will be the first RCT to test whether treating periodontal disease among pre-conception women reduces periodontal disease during pregnancy and prevents adverse birth outcomes. If the effect of pre-pregnancy periodontal treatment is confirmed, this intervention could be recommended for application in low- or middle-income countries to improve both oral health and maternal and child health.

Trial Registration: This trial is registered with Chinese Clinical Trial Registry (ChiCTR): ChiCTR-TRC-12001913.