Assessment of Kenyan pregnant women's tolerance to adverse effects of iron and folic acid supplementation: A retrospective study.

Iron and folic acid supplementation is a maternal and fetal health imperative. This study introduced an examination of antenatal tolerance to the adverse effects of the supplements, defined as persisting with supplementation for a longer duration than the group mean. Multiple logistic regression modeled tolerance against maternal and supplement-related factors. The number of adverse effects experienced was not associated with tolerance [p=0.14, adjusted odds ratio (aOR): 0.8 (0.6-3.4)], but counseling on adverse effects was associated with it [p=0.01, aOR: 3.0 (1.3-7.1)]. Nausea (an important side effect as identified by previous compliance analyses), constipation, and black stool (newly identified) were the only distresses significantly associated with the tolerance ([p=0.02, aOR: 4.4 (1.3-14.9)]; [p=0.03, aOR: 2.1 (1.1-4.3)]; and [p=0.047, OR: 4.2 (0.9-19.2)], respectively). Tolerance analysis presented can identify additional pertinent context-specific adverse effects. Intensified counseling on the effects to improve the tolerance and compliance to antenatal iron and folic acid supplementation should be encouraged and supported.