Factors associated with the severity of nutritional anemia during pregnancy in Shenzhen (2021-2023): a...

Nutritional anemia during pregnancy is a major public health concern and a leading contributor to adverse maternal and neonatal outcomes. The determinants of anemia severity remain insufficiently characterized in rapidly urbanizing regions. This study aimed to identify factors associated with the severity of nutritional anemia among pregnant women in Pingshan District, Shenzhen.

A retrospective cross-sectional study was conducted using data from the Shenzhen Maternal and Child Health Management Information System. A total of 4,025 pregnant women diagnosed with nutritional anemia between 2021 and 2023 with complete records were included. Anemia severity was classified based on the lowest hemoglobin concentration during pregnancy as mild or moderate-to-severe. Univariate and multivariable logistic regression analyses were performed to identify independent risk factors.

Among the 4,025 pregnant women included, 1,176 (29.2%) had moderate-to-severe nutritional anemia. In the fully adjusted model, migrant population status was independently associated with an increased risk of moderate-to-severe anemia compared with permanent residents (OR = 1.6, 95% CI: 1.3-1.9). Higher parity was also independently associated with greater anemia severity, with women having two or more prior deliveries exhibiting a 1.4-fold increased risk (OR = 1.4, 95% CI: 1.2-1.8). In addition, after excluding cases in which prenatal risk stratification was elevated solely due to anemia, a high prenatal risk status at the initial antenatal visit remained significantly associated with moderate-to-severe anemia (OR = 1.6, 95% CI: 1.2-2.1). Conversely, a pre-pregnancy BMI ≥ 25 kg/m² was inversely associated with anemia severity (OR = 0.7, 95% CI: 0.5-1.0), while maternal age was not independently associated with anemia severity.

In this urbanized district of Shenzhen, migrant status, higher parity, and elevated prenatal risk were independent factors associated with moderate-to-severe nutritional anemia among women diagnosed with nutritional anemia. Early anemia screening and targeted nutritional interventions for these high-risk subgroups may help reduce anemia severity and improve maternal and neonatal outcomes.