Anaemia is defined as a haemoglobin concentration of less than 11 g/dl.¹ It is the most common medical disorder encountered during pregnancy and is indirectly responsible for 40–60% of maternal deaths in developing countries.² Postpartum anaemia refers to a reduction in haemoglobin (Hb) levels or red blood cell count following childbirth and is associated with symptoms such as fatigue, weakness, pallor, and shortness of breath. According to the Federation of Obstetrics and Gynaecological Society of India (FOGSI), postpartum anaemia is diagnosed when the haemoglobin concentration is below 11 g/dL within one week after delivery and below 12 g/dL at one year postpartum.

Postpartum anaemia typically results from blood loss during delivery, inadequate dietary iron intake, and depleted iron stores during pregnancy. Women who experience complications such as heavy bleeding during delivery (postpartum haemorrhage) or who have pre-existing anaemia during pregnancy are at a significantly higher risk of developing postpartum anaemia.

Over the years, various treatment modalities including oral iron therapy, intramuscular iron therapy, intravenous iron therapy, and blood transfusion have been used for the management of postpartum anaemia.³ Oral iron supplementation remains the first-line treatment for most patients due to its wide availability, particularly at peripheral health centres and subcentres.⁴ Among the various oral iron preparations, ferrous sulphate is the most commonly used and is readily available through government supply in India.

Postpartum anaemia is a global health problem and, in most women with mild anaemia, it is self-limiting and resolves within a week. However, in resource-poor countries, it remains a major contributor to maternal morbidity and mortality.⁵ In such settings, anaemia may result from inadequate nutritional intake, parasitic infestations, or malaria, and may be further aggravated by the physiological demands of pregnancy and blood loss during childbirth (WHO 2017).⁶

Postpartum anaemia has been associated with an increased prevalence of symptoms such as breathlessness, fatigue, palpitations, and maternal infections.⁷ These symptoms can impair a woman’s ability to care for her newborn and may adversely affect the emotional bonding between mother and child.⁸ Blood transfusion has traditionally been used in the treatment of postpartum anaemia; however, it carries several risks including transfusion reactions due to contamination with leukocytes or red blood cells, transmission of infections such as hepatitis, Human Immunodeficiency Virus (HIV), and cytomegalovirus, fluid overload, allergic reactions, lung injury, and air embolism. Additionally, the cost of blood transfusion—including donor screening, storage, and sterile administration—adds a substantial financial burden, particularly in under-resourced countries.⁹

In view of the risks associated with blood transfusion and existing financial constraints, increasing attention has been directed towards alternative treatment options such as iron supplementation, both oral and parenteral (intravenous, intramuscular, or subcutaneous), as well as erythropoietin therapy. Erythropoietin is an endogenous hormone that stimulates red blood cell production.

Oral iron therapy has been used for centuries in the treatment of iron deficiency anaemia¹⁰ and continues to be widely used during pregnancy.¹⁰ However, oral iron is often associated with gastrointestinal side effects including constipation, nausea, and gastric irritation, which may limit patient compliance. Parenteral iron therapy, while effective, may be associated with pain and erythema at the injection site and, rarely, anaphylactic reactions characterised by itching, redness, angioedema, vascular collapse, and bronchospasm.

The aim of the present study is to evaluate the safety and efficacy of intravenous ferric carboxymaltose compared with oral iron therapy in the treatment of postpartum anaemia, with postpartum haemoglobin as the primary outcome measure. The objective of this study is to compare the efficacy of intravenous and oral iron in improving haematological indices, specifically haemoglobin (Hb) levels and serum ferritin levels, in women with postpartum anaemia.

This prospective, observational, and comparative study was conducted at a tertiary care centre in Kolkata from July 2023 to December 2024. The study included women aged ≥18 years diagnosed with postpartum anaemia (haemoglobin 7–9 g/dL) who were willing to provide informed consent and comply with follow-up visits. Exclusion criteria included known hypersensitivity to iron therapy; anaemia due to causes other than iron deficiency such as haemoglobinopathies or chronic diseases; history of iron overload disorders including hemochromatosis; severe anaemia (Hb <7 g/dL) requiring blood transfusion; haemoglobin levels >9 g/dL; malabsorption syndromes affecting iron absorption; chronic medical conditions such as chronic renal failure, chronic liver disease, or chronic hypertension; significant postpartum complications including sepsis, postpartum haemorrhage requiring blood transfusion, or any life-threatening condition; folic acid or vitamin B12 deficiency; and unwillingness to participate in the study. Demographic and clinical details including age, parity, body weight, booking status, educational and socioeconomic status, history of antenatal anaemia, gestational age at delivery, singleton or multiple pregnancy, mode of delivery, estimated blood loss during delivery, type and dose of treatment received (intravenous or oral iron), and rise in haemoglobin and serum ferritin levels at 2 weeks and 6 weeks after initiation of therapy were recorded for all eligible participants. Data were entered into a Microsoft Excel spreadsheet (Office 2021, Windows 10) and analysed using SPSS software (version 27.0; SPSS Inc., Chicago, IL, USA) and GraphPad Prism (version 5). Patients with postpartum anaemia were divided into two groups: Group A received intravenous ferric carboxymaltose, with the total dose calculated using the Ganzoni formula, a maximum of 1000 mg administered intravenously in a single sitting over 30 minutes, and additional doses given after one week if required; Group B received oral ferrous sulphate tablets (200 mg) twice daily for six weeks. The primary outcomes were the rise in haemoglobin and serum ferritin levels at 2 weeks and 6 weeks after initiation of therapy. Secondary outcomes included improvement in clinical symptoms such as fatigue, pallor, and breathlessness; patient satisfaction; occurrence of adverse effects (gastrointestinal side effects with oral iron and hypersensitivity reactions with intravenous iron); compliance; and tolerability of therapy. Patients in both groups were evaluated at baseline, at 2 weeks, and at 6 weeks after initiation of treatment for changes in haemoglobin and serum ferritin levels. Institutional ethical approval was obtained from the Institutional Ethics Committee.

The sample size for this study was calculated to be 126, with 63 participants in each Group A & Group B, as per the formula N = [2 × (Zα/2 + Zβ)² × σ²] / δ² where N = sample size, Zα/2 = 1.96 (standard normal variate for 5% significance level, two-tailed), Zβ = 0.84 (for 80% power), σ = standard deviation of haemoglobin levels from previous studies, δ = expected minimum difference in haemoglobin improvement between IV and oral groups.

As per this study, the mean age (mean ± SD) of patients was 28.0794 ± 5.3016 in IV Ferric Carboxymaltose and 27.0317 ± 5.2332 in Oral Ferrous Sulphate groups. The distribution of mean age, parity, socioeconomic status, mean gestational age at delivery, blood loss during delivery were not statistically significant. The mean weight (mean ± SD) in IV Ferric Carboxymaltose was 53.6667 ± 5.9758 kg and in oral Ferrous Sulphate was 56.1746 ± 6.1080 kg (p = 0.0214). In IV Ferric Carboxymaltose, the mean dose required (mean ± SD) was 903.9683 ± 82.9407 mg, and in oral Ferrous Sulphate it was 200.0000 ± 0.0000 mg (p < 0.0001).

The baseline demographic & obstetric characteristics of the study participants is shown in Table 1, while a comparison of Hb and Ferritin levels between Intravenous & Oral Iron groups shown in Tables 2 & 3. Figure 1 shows trend of Hb and Ferritin levels over time.

Treatment distribution between oral ferrous sulphate and intravenous ferric carboxymaltose was comparable across age groups, with no significant age-related preference observed. This is consistent with findings by Zhao G et al. (2015),¹¹ who demonstrated balanced allocation of iron therapy among women aged ≥18 years with uncomplicated singleton pregnancies. Educational status differed significantly between the two treatment groups (p = 0.0112). Women receiving intravenous ferric carboxymaltose were predominantly educated up to the higher secondary level, whereas the oral ferrous sulphate group showed a more evenly distributed educational profile. The proportion of multifetal and singleton pregnancies was comparable between the intravenous ferric carboxymaltose and oral ferrous sulphate groups, indicating no significant difference in pregnancy type distribution. Similar inclusion of uncomplicated singleton pregnancies has been reported by Zhao G et al. (2015),11 in their randomized study evaluating iron–folate supplementation and maternal and neonatal iron status. The majority of patients in both treatment groups were "Booked" (i.e., formally registered for care), with 77.8% of patients receiving IV Ferric Carboxymaltose and 79.4% of patients receiving Oral Ferrous Sulphate falling into this category. This suggests that a similar proportion of booked patients received each treatment type. No statistically significant association was observed between treatment choice and a history of antenatal anaemia. Among the participants, anaemia was present in 60.3%, with comparable use of oral ferrous sulphate and intravenous ferric carboxymaltose (χ² = 0.5305; p = 0.4663). Treatment choice did not differ significantly by mode of delivery, with comparable use of intravenous ferric carboxymaltose and oral ferrous sulphate among women undergoing caesarean and vaginal deliveries. The frequency of treatment differed significantly between the two groups. Patients treated with intravenous ferric carboxymaltose received a single-dose regimen, whereas those receiving oral ferrous sulphate were administered twice-daily doses for six weeks. This difference in treatment frequency was statistically significant (χ² = 126.0000; p < 0.0001). Adverse effects differed significantly between the two groups. Gastrointestinal side effects were more common with oral ferrous sulphate (52.4%) compared to intravenous ferric carboxymaltose (6.3%), while the majority of patients receiving intravenous ferric carboxymaltose (93.7%) reported no adverse effects versus 47.6% in the oral iron group. A correlation analysis between Hb and Ferritin levels was done. A strong positive correlation between Hb levels at 2 & 6 weeks (r = 0.80) suggests that patients with higher Hb at 2 weeks continue improving at 6 weeks. Ferritin at 2 & 6 weeks is highly correlated (r = 0.22) suggesting that IV Iron maintains higher iron stores longer. Strong correlation between Hb at 6 Weeks & Ferritin at 2 Weeks (r = 0.60) suggests that early ferritin increase contributes to later hemoglobin rise. Moderate correlation between Ferritin & Hb suggests that higher Ferritin levels contribute to better Hb recovery. Ferritin rise at 2 weeks is a strong predictor of Hb rise at 6 weeks. IV Iron’s rapid ferritin boost likely contributes to its superior Hb improvement. IV Iron Patients reached Hb > 10 g/dL in 4.4 weeks on average. Oral Iron Patients took the full 6 weeks (slower response). 22 IV Iron patients achieved success in just 2 weeks, while no Oral Iron patients reached the target this early. This confirms that IV Iron works significantly faster in correcting postpartum anemia.

Intravenous Ferric Carboxymaltose is a safe, well-tolerated, and more effective alternative to oral Ferrous Sulphate for the treatment of postpartum anaemia. It produces a faster and significantly greater improvement in haemoglobin and serum ferritin levels, with fewer adverse effects and better compliance. Intravenous iron may therefore be considered a preferable option for the rapid correction of postpartum anaemia, particularly in women requiring early recovery.

FUNDING

Nothing such.

CONTRIBUTION TO AUTHORSHIP

PKS & AB wrote the first draft of the paper. DM statistically analyzed the data. PKS, AB, DM & RB edited and revised the article, and all the authors approved the final draft.

COMPETING INTERESTS

None declared.

PATIENT CONSENT

Obtained.

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