De Silva DA, et al. - Researchers utilized near-national birth certificate data to assess the link between interpregnancy interval (IPI) and severe maternal morbidity and account for known under-reporting employing probabilistic bias analysis. They evaluated maternal blood transfusion, admission to intensive care unit (ICU), uterine rupture (among women with a prior caesarean delivery) and third- or fourth-degree perineal laceration (among vaginal deliveries) by IPI classes (< 6, 6-11, 12-17, 18-23, 24-59 and 60+ months). Relative to IPI 18 to 23 months, it was shown in adjusted models that the risk of maternal transfusion followed a U-shaped curve with IPI, while an increment in the risk of ICU admission and perineal laceration was evident with longer IPI. In IPI < 6 months, the highest risk of uterine rupture was reported. Except for maternal transfusion, these revelations persisted irrespective of the extent or type of misclassification examined in bias analyses. Findings revealed that links between IPI and maternal morbidity differed by the outcome, even following the adjustment for misclassification of severe maternal morbidity. Considering variations across maternal health outcomes when counselling and offering suggestions about optimal birth spacing was recommended by the experts.