Do side-effects reduce compliance to iron supplementation? A study of daily- and weekly-dose regimens in pregnancy.

Side-effects of iron supplementation lead to poor compliance. A weekly-dose schedule of iron supplementation rather than a daily-dose regimen has been suggested to produce fewer side-effects, thereby achieving a higher compliance. This study compared side-effects of iron supplementation and their impact on compliance among pregnant women in Bangladesh. These women were assigned to receive either weekly doses of 2 x 60 mg iron (one tablet each Friday morning and evening) or a daily dose of 1 x 60 mg iron. Fifty antenatal care centres were randomly assigned to prescribe either a weekly- or a daily-supplementation regimen (86 women in each group). Side-effects were assessed by recall after one month of supplementation and used for predicting compliance in the second and third months of supplementation. Compliance was monitored using a pill bottle equipped with an electronic counting device that recorded date and time whenever the pill bottle was opened. Of five gastrointestinal side-effects (heartburn, nausea, vomiting, diarrhoea, or constipation) assessed, vomiting occurred more frequently in the weekly group (21%) than in the daily group (11%, p<0.05). Compliance (ratio between observed and recommended tablet intake) was significantly higher in the weekly-supplementation regimen (93%) than in the daily-supplementation regimen (61%, p<0.05). Overall, gastrointestinal side-effects were not significantly associated with compliance. However, the presence of nausea and/or vomiting reduced compliance in both the regimens-but only among women from the lower socioeconomic group. In conclusion, weekly supplementation of iron in pregnancy had a higher compliance compared to daily supplementation of iron despite a higher frequency of side-effects. The findings support the view that gastrointestinal side-effects generally have a limited influence on compliance, at least in the dose ranges studied. Efforts to further reduce side-effects of iron supplementation may not be a successful strategy for improving compliance and effectiveness of antenatal iron supplementation

Anaemia and iron deficiency during pregnancy in rural Bangladesh.

OBJECTIVE: To study the prevalence of anaemia and its association with measures of iron deficiency (ID) among a group of pregnant women. DESIGN: Cross-sectional survey. SETTING: Pregnant women identified through house-to-house visits and participating in community-based antenatal care activities in a rural location of Mymensingh, Bangladesh. SUBJECTS: The estimates are based on 214 reportedly healthy pregnant women in their second trimester. Information on socio-economic status and reproductive history were obtained through home visits and venous blood samples were collected at antenatal care centres. Haemoglobin concentration (Hb) was measured by HemoCue, serum ferritin (sFt) by radioimmunoassay and serum transferrin receptor (sTfR) by enzyme-linked immunosorbent assay methods. ID was defined as presence of either low sFt (8.5 mg l(-1)). RESULTS: The prevalence of anaemia (Hb /=110 g l(-1)) also had ID, but the prevalence was significantly lower than that observed in anaemic women (P=0.001). CONCLUSIONS: Despite the high prevalence of anaemia, severe cases were absent. The prevalence of ID increased at lower Hb. However, an increased prevalence was also found among women in the highest category of Hb

Efficacy and trial effectiveness of weekly and daily iron supplementation among pregnant women in rural Bangladesh: disentangling the issues.

BACKGROUND: According to our current understanding, iron absorption with weekly iron supplements is not higher than that with daily supplements (ie, there is no mucosal block). However, community-based trials have repeatedly shown that a weekly regimen is as effective as a daily one. Furthermore, when differences in absorption are found, they are commonly smaller than would be expected on the basis of differences in the amount of iron provided. The possibility of differential compliance between the regimens needs to be evaluated to explain these findings. OBJECTIVE: Taking compliance into account, we compared the efficacy and trial effectiveness of weekly and daily iron supplementation during pregnancy. DESIGN: In Bangladesh, 50 antenatal centers were randomly assigned to prescribe either 2 doses of 60 mg Fe once weekly or 1 dose of 60 mg Fe/d. Compliance was monitored by using a pill bottle equipped with an electronic counting device. Hemoglobin concentrations were measured at baseline and after 4, 8, and 12 wk of supplementation. RESULTS: There was no differential effect per iron tablet between weekly and daily regimens. A 12-wk daily regimen (68% compliance) produced a small but significantly greater hemoglobin response than did the weekly regimen (104% compliance). The first 20 tablets consumed produced most of the effect; after 40 tablets, there was no further response. CONCLUSIONS: There was no evidence of a mucosal block in the daily regimen. Over 12 wk, 50% of the amount of iron in a daily regimen was sufficient for maximum hemoglobin effect. The weekly regimen provided a large part of this amount, explaining the limited difference in effect. It appears that the current international recommendation for iron supplementation in pregnancy is higher than necessary