Abstract / Summary
The objective of the study is to compare the hematologic response to three oral iron regimens during pregnancy and to evaluate differences in treatment efficacy across distinct obstetric populations. Specifically, we compared ferrous sulfate 100 mg once a day with two doses of Iron Hydroxide Adipate Tartrate (IHATTM), 30 mg once a day and 60 mg daily (i.e., 30 mg twice a day) after 24 weeks of supplementation. This retrospective observational study was conducted at the Department of Public Health, University of Naples Federico II, Naples, Italy. We analyzed clinical data retrospectively collected from 60 pregnant women with iron deficiency anemia managed between September 2025 and March 2026, who completed 24 weeks of oral iron therapy and distributed across five predefined population clusters: singleton low-risk pregnancy, multiple gestation, increased surgical risk, high-risk pregnancy, and gastrointestinal disorders affecting iron absorption. Each cluster included 12 participants equally allocated to three treatment groups: ferrous sulfate 100 mg (arm A), IHATTM 30 mg (arm B), and IHATTM 60 mg (arm C). The primary outcome was the change in hemoglobin concentration from baseline to 24 weeks after treatment initiation. Subgroup analyses were performed according to population cluster. A total of 60 participants were included (20 per treatment group). Hemoglobin levels increased progressively during follow-up in all treatment arms. At 24 weeks, the mean hemoglobin increase from baseline was 0.87 ± 0.29 g/dL in the ferrous sulfate group, 1.48 ± 0.34 g/dL in the IHATTM 30 mg group, and 1.96 ± 0.41 g/dL in the IHATTM 60 mg group (p < 0.001). Ferritin levels increased by 7.4 ± 2.7 ng/mL, 14.6 ± 3.3 ng/mL, and 21.3 ± 4.6 ng/mL in the three treatment groups, respectively (p < 0.001). Gastrointestinal adverse events were more frequent with ferrous sulfate (55%) compared with IHATTM 60 mg (25%) and IHATTM 30 mg (0%) (p = 0.0004). Subgroup analysis across the five population clusters showed a consistent pattern, with greater hemoglobin increases observed with IHATTM compared with ferrous sulfate, including among women with gastrointestinal conditions affecting iron absorption. In this retrospective observational study, oral IHATTM demonstrated greater improvement in hemoglobin and iron parameters compared with conventional ferrous sulfate after 24 weeks of treatment, with the largest effect observed with the 60 mg dose. This pattern was consistent across the predefined obstetric populations and was accompanied by fewer gastrointestinal adverse events.