Oral iron use after intravenous ferric carboxymaltose in pregnancy and short-term hematologic response: A retrospective cohort study.

OBJECTIVE: To assess short-term hematologic response to a single 1000 mg dose of intravenous ferric carboxymaltose in pregnancy and determine whether subsequent oral iron use was associated with additional hematologic benefit. STUDY DESIGN: This retrospective cohort included 955 singleton pregnancies treated at Kayseri City Hospital between January 2021 and May 2025. Women receiving intravenous ferric carboxymaltose alone were compared with those with documented oral iron use after infusion and before the first antepartum follow-up complete blood count. Primary outcomes were hemoglobin and hematocrit changes. Multivariable linear regression adjusted for maternal age, parity, gestational age at treatment, baseline hematologic value, and follow-up interval. RESULTS: The intravenous-only and intravenous-plus-oral iron groups included 867 and 88 pregnancies, respectively. Overall, hemoglobin increased from 9.45 ± 1.27 to 11.48 ± 1.44 g/dL and hematocrit from 29.45 ± 3.27 % to 34.71 ± 3.75 %. Changes in hemoglobin (2.02 ± 1.39 vs 2.16 ± 1.21 g/dL; p = 0.318) and hematocrit (5.23 ± 3.89 vs 5.59 ± 3.05 percentage points; p = 0.308) did not differ between groups. Oral iron use was not independently associated with a greater change in hemoglobin (B = 0.188, 95 % CI - 0.049 to 0.426; p = 0.121) or hematocrit (B = 0.529, 95 % CI - 0.165 to 1.223; p = 0.135). CONCLUSION: Intravenous ferric carboxymaltose was associated with substantial short-term hematologic improvement. Subsequent oral iron use was not associated with a measurable additional response.