Iron through a drip beat iron tablets in pregnancy across 29 trials, with fewer transfusions

Iron deficiency anaemia is one of the most common problems in pregnancy, and the usual first treatment is iron tablets. Many women find them hard to take because of nausea and constipation. A systematic review and meta-analysis published in JAMA Network Open on 23 September 2026, led from Brown University in the US, updated a 2018 review comparing intravenous (IV) iron with oral iron. It added 10 new randomised trials and removed one that had been retracted, for 29 trials with 11,771 women.

Compared with tablets, IV iron was linked with maternal haemoglobin 0.59 g/dL higher at delivery (15 trials), maternal ferritin 50.93 ng/mL higher (8 trials) and higher ferritin in newborns (21.38 ng/mL, 8 trials), a sign of better iron stores for the baby. Blood transfusions during the delivery stay were 37% less common (relative risk 0.63, 14 trials), and the benefit showed among women who started with haemoglobin of 9 g/dL or less. No serious adverse events were reported, and mild side effects were less common with IV iron (relative risk 0.56).

The authors say the results may support a greater role for IV iron in treating anaemia in pregnancy. The choice still depends on how severe the anaemia is, how far along the pregnancy is, cost and access to a clinic that can give infusions. Iron-rich food remains part of the plan, but it cannot correct established anaemia by itself.