Table 2.

Inclusion and exclusion criteria for the IMPROVE feasibility trial

Inclusion criteria	Exclusion criteria
1. Aged ≥ 18 years at the time of recruitment	1. Positive diagnosis of HIV/AIDS, syphilis, psychosis, diabetes before pregnancy, thyroid disease, or any disorder causing vitamin D hypersensitivity (e.g. sarcoidosis and other lymphomatous disorders)
2. > 20 weeks gestation at first prenatal visit	2. Lactose intolerance, milk allergy, history of renal stones or family history of renal stone and hyperparathyroidism
3. Positive diagnosis of periodontitis (≥ 1 tooth with at least one site with ≥ 4 mm of clinical attachment loss (CAL) and presence of bleeding on probing)	3. Extensive dental cavity (crowns of several teeth destroyed by caries) and loss of tooth structure or use of fixed dental braces
4. Cognitively and physically able to complete an interview and oral examination and willing to participate, including provision of blood samples.	4. Use of antibiotics or any immune-suppressants or medication known to affect vitamin D/calcium metabolism
	5. Consumption of ≥ 4 servings/day of dairy products or taking vitamin D supplements > 400 IU/day