Interpretation
The CPMs in this study relied on information that is routinely known at the time of the first antenatal visit, and that is temporally remote from when most morbid events arise – around the time of birth.9 Our main CPM shows the potential utility of harnessing data in early pregnancy to predict a variety of later adverse maternal outcomes. Consistent with previous research on postnatal mortality,21 our CPM for all-cause mortality showed substance use, alcohol use, and psychiatric conditions to be significant predictors of death up to 365 days postpartum.
Severe maternal morbidity rates have stagnated within Western nations, yet evidence-based strategies to reduce their burden are lacking.9 With further refinement of this CPM, a clinical risk calculator could be developed to help triage women for enhanced surveillance or referral to subspecialty care or shared-care antenatal pathways – decisions that at present rely principally on clinical judgment. The development and refinement of future CPMs for severe maternal morbidity should consider adding first-trimester placental biomarkers and other maternal biomarkers alongside routinely measured clinical variables, such as blood pressure and weight. The availability of such variables might facilitate prediction of the whole of severe morbidity as well as cause-specific outcomes, and better inform individualized and targeted prevention.35