The World Health Organization (WHO) now recommends prenatal calcium supplementation for prevention of preeclampsia in populations with inadequate dietary intake. This study seeks to compare the effect of two dosing strategies on the amount of supplement ingested by pregnant women and adherence to related recommendations.

This study is a non-inferiority trial that compares the effect of a dosing strategy involving lower overall dose and fewer administrations per day to the current WHO recommendation. The comparator arm, Regimen B, prescribes 3 doses per day (consistent with current WHO standard) and was found to be burdensome in qualitative studies. The experimental arm, Regimen A, prescribes 2 doses per day and has been associated with greater satisfaction. On face value Regimen A should result in 33% less amount of supplement ingested than Regimen B. However, we hypothesize that the difference in amount ingested, when rolled out in routine practice will be MUCH LESS than that BECAUSE THE LOWER DOSE REGIMEN RESULTS IN HIGHER LEVELS OF ADHERENCE. We hypothesize that THE DIFFERENCE IN AMOUNT CONSUMED WILL BE NEGLIGIBLE OR will not exceed 15%. Hence, we hypothesize that Regimen A is not inferior to Regimen B in terms of total amount of supplement ingested (within a 15% margin of inferiority).

Inclusion Criteria:

• Attendance at ANC clinic in a primary care facility in Kakamega north

Exclusion Criteria:

• Gestational age < 16 weeks,
• Gestational age > 30 weeks,
• Dietary or medicinal consumption of adequate calcium (according to the screening survey),
• Intention to leave study community before 8weeks from date of interview