TY - JOUR
T1 - Effect of iron content on the tolerability of prenatal multivitamins in pregnancy
AU - Nguyen, Patricia
AU - Nava-Ocampo, Alejandro
AU - Levy, Amalia
AU - O'Connor, Deborah L.
AU - Einarson, Tom R.
AU - Taddio, Anna
AU - Koren, Gideon
N1 - Funding Information:
PN drafted the forms and questionnaires for data collection, enrolled study subjects, conducted telephone interviews, collected and analyzed data, and drafted the manuscript. AN–O contributed to data analysis, particularly the survival curve analysis, and manuscript editing. AL contributed to data analysis, particularly the survival curve analysis, and manuscript editing. DLO'C contributed to drafting and editing the manuscript. TRE contributed to data analysis and manuscript editing. AT contributed to data analysis. GK conceived of the study and participated in its design and coordination, and contributed to manuscript editing. All authors read and approved the final manuscript. The study was supported by a grant from Duchesnay Inc., Laval, Quebec, Canada.
PY - 2008/5/15
Y1 - 2008/5/15
N2 - Background: Gastrointestinal irritability can deter pregnant women from starting or continuing prenatal multivitamin supplementation. In a previous study, suboptimal tolerability was observed among pregnant women taking a large tablet (18 mm × 8 mm × 8 mm) multivitamin with high elemental iron content (60 mg as ferrous fumarate). The objective of the present study was to compare rates of adherence and reported adverse events among pregnant women who were randomized to commence supplementation with a small-tablet prenatal multivitamin, containing either low or high iron content. Methods: Pregnant women who called the Motherisk Program (Hospital for Sick Children, Toronto) and had not started taking or had discontinued any multivitamin due to adverse events were included in this prospective, randomized, open-label, 2-arm study. Women were randomized to take a small-size (16 mm × 9 mm × 4 mm), low elemental iron content (35 mg as ferrous fumarate) multivitamin ('35 mg' group); or a small-size (5 mm radius, 5 mm thickness), high elemental iron content (60 mg as ferrous sulphate) multivitamin ('60 mg' group). Follow-up interviews documented pill intake and adverse events. Rates of adherence and adverse events were compared between groups using chi-squared tests and Kaplan-Meier survival curves. Results: Of 167 randomized women, 92 in the '35 mg' group and 75 in the '60 mg' group were included in the analysis. Despite ideal conditions and regular follow-ups, mean adherence based on pill intake recall, in both groups was approximately 50%. No statistically significant difference was detected in proportions of women who actually started taking either multivitamin. Among those who started, no difference was detected in rates of adherence or reported adverse events. Conclusion: The present results suggest that iron content is not a major determinant of adherence to prenatal multivitamins. Combined with our previous study, tablet size may be the more definitive factor affecting adherence.
AB - Background: Gastrointestinal irritability can deter pregnant women from starting or continuing prenatal multivitamin supplementation. In a previous study, suboptimal tolerability was observed among pregnant women taking a large tablet (18 mm × 8 mm × 8 mm) multivitamin with high elemental iron content (60 mg as ferrous fumarate). The objective of the present study was to compare rates of adherence and reported adverse events among pregnant women who were randomized to commence supplementation with a small-tablet prenatal multivitamin, containing either low or high iron content. Methods: Pregnant women who called the Motherisk Program (Hospital for Sick Children, Toronto) and had not started taking or had discontinued any multivitamin due to adverse events were included in this prospective, randomized, open-label, 2-arm study. Women were randomized to take a small-size (16 mm × 9 mm × 4 mm), low elemental iron content (35 mg as ferrous fumarate) multivitamin ('35 mg' group); or a small-size (5 mm radius, 5 mm thickness), high elemental iron content (60 mg as ferrous sulphate) multivitamin ('60 mg' group). Follow-up interviews documented pill intake and adverse events. Rates of adherence and adverse events were compared between groups using chi-squared tests and Kaplan-Meier survival curves. Results: Of 167 randomized women, 92 in the '35 mg' group and 75 in the '60 mg' group were included in the analysis. Despite ideal conditions and regular follow-ups, mean adherence based on pill intake recall, in both groups was approximately 50%. No statistically significant difference was detected in proportions of women who actually started taking either multivitamin. Among those who started, no difference was detected in rates of adherence or reported adverse events. Conclusion: The present results suggest that iron content is not a major determinant of adherence to prenatal multivitamins. Combined with our previous study, tablet size may be the more definitive factor affecting adherence.
UR - http://www.scopus.com/inward/record.url?scp=44649106890&partnerID=8YFLogxK
U2 - 10.1186/1471-2393-8-17
DO - 10.1186/1471-2393-8-17
M3 - Article
C2 - 18482454
AN - SCOPUS:44649106890
SN - 1471-2393
VL - 8
JO - BMC Pregnancy and Childbirth
JF - BMC Pregnancy and Childbirth
M1 - 17
ER -