Medication-related risk factors for preterm birth in Kitui county, Kenya

Abstract

Introduction: Premature infants contribute substantially to infant morbidity and mortality especially in low resource areas. Understanding the factors that contribute to pre-mature labour in these areas would greatly influence infant morbidity, mortality and reduce paediatric healthcare costs. Objective:To investigate the use of herbal remedies, self-medication and prescription medications in pregnancy as risk factors for preterm birth in Kitui County among the immediate post-partum mothers. Methods: An unmatched case control (1:4) study was conducted in Kitui and Mwingi District Hospitals in Kitui County. A total of 560immediate postpartum mothers were sampled of which 107 were mothers with preterm birth (Cases) whereas 453 were mothers with term birth (Controls). Retrospective review of medical records was conducted to collect data pertaining to medical history and use of prescription drugs during pregnancy. Structured questionnaires were administered to mothers to collect data on demographic characteristics, socio-economic status, self-medication practices and use of herbal remedies. Data was analyzed to describe the distribution of demographic variables between cases and controls using the Pearson Chi square test. Logistic regression was used to test for association between various predictors such as self- medication, use of herbal remedies and prescription drugs and the main outcome variable, pre-term birth. Multivariate modelling was used to identify the risk factors for preterm birth while controlling for confounding. Results:Predictors of preterm birth were: Herbal use in the 1st trimester lasting two to five days (OR=11.10 [4.34-28.41], p<0.01), herbal use in the 1st trimester lasting six to 10 days (OR= 44.87 [4.99-403.87], p<0.01) and herbal use in the 2nd trimester for six to 10 days (OR= 16.43 [4.53-59.57], p<0.01). Self-medication with the following medications in the 1st trimester for 2 to 5 days: Chlorpheniramine (OR=2.64 [1.22-19.65], p=0.012), Paracetamol (OR=1.34 [1.09-6.73], p=0.043), Amoxycillin (OR=5.72 [1.60-20.84]. Factors were associated with lower risk of preterm birth: Amoxicillin prescribed in the 1st trimester (OR=0.09 [0.01-0.66], p=0.043), ferrous sulphate, 2nd trimester for more than 31 days (OR=0.22 [0.13-0.35], p<0.001), folic acid from 2nd trimester for more than 31 days (OR=0.20 [0.12-0.34], p=0.02) and FDA category A medications (OR=0.27 [0.07-0.42], p=0.001). Conclusion and Recommendations: Use of herbal remedies and self-medication in pregnancy is common among the women in Kitui County and it is a major risk factor for preterm birth. Prescribers should be sensitized on safe medication use in pregnancy and prompt management of maternal infections. Folic acid and ferrous sulphate supplementation throughout pregnancy should be strengthened.