Insufficient iodine nutrition status and the risk of pre-eclampsia: a systemic review and meta-analysis

source extracted confidence: high 2026-04-09
#africa #cross-sectional-studies #female #humans #iodine

Insufficient iodine nutrition status and the risk of pre-eclampsia: a systemic review and meta-analysis

Businge et al., 2021 | BMJ Open | Meta Analysis

Citation

Businge Charles Bitamazire, Usenbo Anthony, ... Kengne A P. Insufficient iodine nutrition status and the risk of pre-eclampsia: a systemic review and meta-analysis. BMJ Open. 2021-Feb-10;11(2):e043505. doi:10.1136/bmjopen-2020-043505

Abstract

BACKGROUND: Although subclinical hypothyroidism in pregnancy is one of the established risk factors for pre-eclampsia, the link between iodine deficiency, the main cause of hypothyroidism, and pre-eclampsia remains uncertain. We conducted a systematic review to determine the iodine nutrition status of pregnant women with and without pre-eclampsia and the risk of pre-eclampsia due to iodine deficiency. METHODS: MEDLINE, EMBASE, Google Scholar, Scopus and Africa-Wide Information were searched up to 30th June 2020. Random-effect model meta-analysis was used to pool mean difference in urinary iodine concentration (UIC) between pre-eclamptic and normotensive controls and pool ORs and incidence rates of pre-eclampsia among women with UIC <150 µg/L. RESULTS: Five eligible studies were included in the meta-analysis. There was a significant difference in the pooled mean UIC of 254 pre-eclamptic women and 210 normotensive controls enrolled in three eligible case-control studies (mean UIC 164.4 µg/L (95% CI 45.1 to 283.6, p<0.01, I2 >50)). The overall proportions of pre-eclampsia among women with UIC <150 µg/L and UIC >150 µg/L in two cross-sectional studies were 203/214 and 67/247, respectively, with a pooled OR of 0.01 (95% CI 0 to 4.23, p=0.14, I2 >50) for pre-eclampsia among women with UIC >150 µg/L. The overall incidence of pre-eclampsia among women with UIC <150 µg/L and UIC >150 µg/L in two cohort studies was 6/1411 and 3/2478, respectively, with a pooled risk ratio of 2.85 (95% CI 0.42 to 20.05, p=0.09, I2 <25). CONCLUSION: Although pre-eclamptic women seem to have lower UIC than normotensive pregnant women, the available data are insufficient to provide a conclusive answer on association of iodine deficiency with pre-eclampsia risk. PROSPERO REGISTRATION NUMBER: CRD42018099427.

Key Findings

Five eligible studies were included in the meta-analysis. There was a significant difference in the pooled mean UIC of 254 pre-eclamptic women and 210 normotensive controls enrolled in three eligible case-control studies (mean UIC 164.4 µg/L (95% CI 45.1 to 283.6, p<0.01, I2 >50)). The overall proportions of pre-eclampsia among women with UIC <150 µg/L and UIC >150 µg/L in two cross-sectional studies were 203/214 and 67/247, respectively, with a pooled OR of 0.01 (95% CI 0 to 4.23, p=0.14, I2 >5

Outcomes Measured

  • Requires manual extraction

Population

Field Value
Population pregnant women
Sample Size See abstract
Age Range See abstract
Condition deficiency

MeSH Terms

  • Africa
  • Cross-Sectional Studies
  • Female
  • Humans
  • Iodine
  • Nutritional Status
  • Pre-Eclampsia
  • Pregnancy

Evidence Classification

  • Level: Meta Analysis
  • Publication Types: Journal Article, Meta-Analysis, Research Support, Non-U.S. Gov't, Systematic Review
  • Vertical: iodine

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09