Interventions
The intervention was intravenous ferric carboxymaltose (FCM), 500 mg or 1000mg, in 250ml of normal saline, infused over 30 minutes. At the first appointment after screening, FCM at the randomised dose was administered.
Iron status was monitored at five study timepoints: 4 weeks after the initial infusion, then at 6 weeks-, 3-, 6- and 12- months postpartum, or at the time of next pregnancy, whichever came first. The diagnostic criteria indicating persistent ID and requiring additional IVI were ferritin <30 μg/l plus transferrin saturation <25%, or, if inflammation were present (CRP >7.9 ng/l), ferritin between 30 and 50 μg/l plus a transferrin saturation <20%. If confirmed, ID was treated with a single 500mg FCM infusion in both groups.