European Journal of Cardiovascular Medicine

Anemia during pregnancy remains a significant global health challenge, particularly in low- and middle-income countries, where it contributes to increased maternal and perinatal morbidity and mortality (1). Iron deficiency anemia (IDA) accounts for approximately 50% of anemia cases in pregnancy, largely due to increased iron demands, hemodilution, and inadequate dietary intake (2). The World Health Organization defines anemia in pregnancy as a hemoglobin concentration below 11 g/dL and estimates its prevalence to be over 40% worldwide (3).

Oral iron supplementation has long been the standard therapy for managing IDA in pregnancy. It is cost-effective and widely available; however, its efficacy is often limited by poor gastrointestinal tolerance, non-compliance, and variable absorption (4,5). Common side effects such as nausea, constipation, and metallic taste often lead to suboptimal adherence, which may delay hematologic recovery (6). Moreover, the slow replenishment of iron stores with oral therapy can be inadequate in moderate to severe cases or in patients nearing the third trimester (7).

Intravenous iron formulations offer an alternative for rapid correction of anemia and replenishment of iron stores. Among them, ferric carboxymaltose (FCM) has emerged as a promising option due to its high iron content, favorable safety profile, and ability to be administered in large single doses without the need for test dosing (8). Several clinical trials have reported superior outcomes with FCM in terms of hemoglobin improvement, serum ferritin restoration, and better tolerability compared to oral iron (9,10).

This study aims to compare the efficacy and safety of intravenous ferric carboxymaltose versus conventional oral iron therapy in pregnant women diagnosed with moderate iron deficiency anemia.

A total of 120 pregnant women between 14 and 28 weeks of gestation diagnosed with moderate iron deficiency anemia (hemoglobin between 7.0–9.9 g/dL and serum ferritin <30 ng/mL) were recruited. Participants with a history of hypersensitivity to iron preparations, hemoglobinopathies, chronic infections, hepatic or renal impairment, or other causes of anemia were excluded.

Study Design and Randomization:
Participants were randomly allocated into two equal groups (n=60 each) using a computer-generated randomization table.

• Group A (Intravenous Iron Group): Received a single dose of ferric carboxymaltose (1000 mg in 250 mL of normal saline) infused intravenously over 15–20 minutes under medical supervision.
• Group B (Oral Iron Group): Received oral ferrous sulfate tablets (100 mg elemental iron) twice daily for a duration of 6 weeks.

Assessment and Follow-Up:
Baseline investigations included hemoglobin, serum ferritin, hematocrit, and complete blood count. These parameters were reassessed at the end of the 6-week intervention period. Any adverse events or side effects during the treatment period were recorded.

Outcome Measures:
The primary outcome was the mean rise in hemoglobin concentration at 6 weeks. Secondary outcomes included changes in serum ferritin levels and the incidence of gastrointestinal side effects such as nausea, constipation, and abdominal discomfort.

Statistical Analysis:
Data were entered into Microsoft Excel and analyzed using SPSS software version 25.0. Quantitative variables were expressed as mean ± standard deviation (SD). Paired t-tests were used for intra-group comparisons, and independent t-tests were applied for inter-group comparisons. A p-value of <0.05 was considered statistically significant.

A total of 120 pregnant women completed the study, with 60 participants in each group. Both groups were comparable at baseline with respect to age, gestational age, initial hemoglobin levels, and serum ferritin concentrations (Table 1).

After 6 weeks of treatment, a statistically significant improvement in hemoglobin and serum ferritin was observed in both groups; however, the increase was significantly greater in the ferric carboxymaltose group compared to the oral iron group (Table 2).

Gastrointestinal side effects were reported more frequently in the oral iron group. Common complaints included nausea, metallic taste, constipation, and abdominal discomfort. The incidence of adverse effects was significantly lower in the intravenous group (Table 3).

Table 1: Baseline Characteristics of the Study Population

Table 2: Hematological Response After 6 Weeks

Table 3: Adverse Events Observed in Study Groups

As shown in Table 2, the intravenous ferric carboxymaltose group achieved a significantly greater rise in hemoglobin and ferritin levels at 6 weeks compared to the oral iron group (p < 0.001). Additionally, Table 3 demonstrates a notably lower incidence of adverse effects in the FCM group, suggesting better tolerability.

Iron deficiency anemia is a common complication during pregnancy, contributing significantly to maternal and fetal morbidity, especially in developing countries (1). In this study, we compared the efficacy and safety of intravenous ferric carboxymaltose (FCM) with conventional oral ferrous sulfate in the treatment of moderate iron deficiency anemia in pregnant women. Our findings indicate that FCM is more effective in improving hemoglobin and iron stores with fewer gastrointestinal side effects compared to oral iron therapy.

The mean increase in hemoglobin was significantly higher in the FCM group (3.2 g/dL) compared to the oral group (2.1 g/dL), which is consistent with previous studies (2,3). Froessler et al. reported similar outcomes, highlighting the rapid hemoglobin response with FCM in antenatal women (4). The greater efficacy of FCM is likely due to its ability to bypass gastrointestinal absorption, allowing for immediate iron availability and utilization for erythropoiesis (5).

Serum ferritin, an indicator of iron stores, also improved more significantly in the FCM group. This is in agreement with studies by Breymann et al. and Seid et al., who reported sustained increases in ferritin levels post-FCM administration (6,7). Replenishment of iron stores is critical for maintaining maternal health and fetal development throughout pregnancy (8).

Adherence to oral iron is frequently compromised due to gastrointestinal side effects such as nausea, constipation, and metallic taste (9). In our study, 38.3% of patients in the oral group reported side effects, compared to only 10% in the FCM group. Similar findings were noted by Qassim et al., where tolerability was significantly better with intravenous iron (10). This difference in tolerability is an essential consideration, particularly in cases where compliance is crucial for therapeutic success.

Despite its benefits, intravenous FCM is often underutilized due to cost concerns and limited awareness among healthcare providers (11). However, when the costs of non-compliance, repeated visits, and persistent anemia are accounted for, FCM may offer better cost-effectiveness in moderate-to-severe anemia management (12).

The World Health Organization recommends the use of intravenous iron in cases where oral iron is poorly tolerated or where rapid replenishment is necessary (13). Our study reinforces this recommendation, especially in second-trimester pregnancies, where time for hematological correction is limited (14).

Limitations of the present study include a relatively short follow-up period and exclusion of severe anemia and high-risk pregnancies. Future studies with larger sample sizes, diverse populations, and long-term neonatal outcomes could offer a more comprehensive understanding of the benefits and risks associated with FCM (15).

Ferric carboxymaltose is more effective and better tolerated than oral iron in the treatment of iron deficiency anemia during pregnancy. It offers a faster improvement in hemoglobin levels and iron stores with fewer gastrointestinal side effects, making it a preferable option for moderate to severe cases or when oral therapy is poorly tolerated.

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