Socioeconomic Status, Region Impact Anemia Rates in Pregnant Women

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A recent systematic review and meta-analysis evaluated cases of anemia among more than 1 million pregnant women in China, revealing a prevalence of approximately 30% with half categorized as a mild presentation.¹

In particular, the prevalence of anemia, as well as iron deficiency and iron deficiency anemia (IDA), was higher across less economically developed regions in China, and rural areas compared with urban areas, with few exceptions for iron deficiency.

“Our analysis found that the prevalence of anemia, iron deficiency, and IDA in pregnant women in China varied by region, urban and rural areas, and the trimester,” wrote the investigative team, led by Yajun Xu, department of nutrition and food hygiene, school of public health, Peking University.

A serious public health concern worldwide, particularly in low- and middle-income countries, anemia can impair physical and cognitive growth, and ultimately socioeconomic development.² Children and women, especially pregnant women, experience a higher risk for the blood condition, affected by genetic, economic, and dietary factors.³

Given inconsistencies in published data on national anemia estimates, Xu and colleagues conducted this review and meta-analysis to determine the prevalence and pattern of anemia, iron deficiency, and IDA among pregnant women across China.¹

A search of relevant studies published between January 2010 and December 2020 identified 722 articles on maternal anemia during pregnancy. Diagnostic criteria from the World Health Organization (WHO) defined anemia as hemoglobin <110 g/L, with mild anemia ranging from 100-109 g/L, moderate from 70-99 g/L, and severe <70 g/L. Iron deficiency was defined as serum ferritin <20 µg/L and IDA as both the presentation of anemia and iron deficiency.

Overall, 57 relevant studies including 1,376,204 pregnant women were used to ascertain the prevalence of anemia in China, and among different subpopulations. Upon analysis, the pooled prevalence of anemia was estimated at 30.7% (95% CI, 26.6–34.7), with approximately half (15.8%) being mild and only 4% being severe.

Notably, a higher proportion of women in their third trimester exhibited anemia, compared with the first and second trimesters. As well, anemia prevalence was shown to more than double in pregnant women living in rural settings, compared with urban settings.

Meanwhile, the pooled prevalence of iron deficiency was 45.6% (95% CI, 37–54.2), indicating nearly half of the pregnant women were iron deficient. However, in contrast to anemia prevalence, iron deficiency was higher for those in urban settings than in rural settings. More than half of pregnant women in the third trimester experienced iron deficiency.

The prevalence of IDA among all pregnant women in China was 17.3% (95% CI, 13.9 – 20.7). Similar to these previous patterns, the prevalence of IDA steadily rose from the first to the third trimester, and it was nearly twice as high in rural than urban settings.

Notably, there were regional variations across the prevalence of anemia, iron deficiency, and IDA. A lower prevalence of each condition was typically observed in the economically advanced eastern region of the country— the prevalence of iron deficiency was higher in the eastern region than in the western region.

“Program and policy changes are recommended to further reduce the prevalence of anemia, iron deficiency, and IDA, including the standardization of lab and diagnostic methods, stipulation of indicators and the relevant reporting mechanisms, requirement of serum ferritin screening in antenatal care services, and development of preventive and treatment measures tailored to different contexts in China,” they added. 

References

1. _{Zhou Y, Lyu Y, Ye W, et al. The Prevalence of Anemia among Pregnant Women in China: A Systematic Review and Meta-Analysis. Nutrients. 2024;16(12):1854. Published 2024 Jun 13. doi:10.3390/nu16121854}
2. _{Stevens GA, Finucane MM, De-Regil LM, et al. Global, regional, and national trends in haemoglobin concentration and prevalence of total and severe anaemia in children and pregnant and non-pregnant women for 1995-2011: a systematic analysis of population-representative data. Lancet Glob Health. 2013;1(1):e16-e25. doi:10.1016/S2214-109X(13)70001-9}
3. _{Peña-Rosas JP, De-Regil LM, Gomez Malave H, Flores-Urrutia MC, Dowswell T. Intermittent oral iron supplementation during pregnancy. Cochrane Database Syst Rev. 2015;2015(10):CD009997. Published 2015 Oct 19. doi:10.1002/14651858.CD009997.pub2}