Background: Intravenous iron sucrose and oral iron therapy are the main therapies for iron deficiency anaemia (IDA), but there is still a debate regarding their efficacy and especially as to which one is the best choice during pregnancy. Methods: A meta-analysis of randomised controlled trials comparing patients treated with intravenous iron sucrose (intravenous group) with those treated with oral iron (oral group) for IDA during pregnancy was performed. The primary outcomes of interest were mean maternal haemoglobin and serum ferritin levels at the end of treatment. Secondary outcomes were treatment-related adverse events and foetal birth weight. Results: Six randomised controlled trials, involving a total of 576 women, were included in the present review. Significant increases in haemoglobin [mean difference (MD), 0.85; 95% confidence interval (CI), 0.31-1.39; p = 0.002] and ferritin levels (MD, 63.32; 95% CI, 39.46-87.18; p < 0.00001) were observed in the intravenous group. Compared with the oral group, there were fewer adverse events in the intravenous group (risk ratio, 0.50; 95% CI, 0.34-0.73; p = 0.0003). There was no significant difference in birth weight between the two groups. Conclusion: For pregnant women who could not tolerate the side effects of oral treatment or required a rapid replacement of iron stores, intravenous iron sucrose was associated with fewer adverse events and was more effective than regular oral iron therapy.