ABSTRACT
Background
Severe maternal morbidity (SMM) has been linked to maternal mortality and several perinatal complications, but the evidence on associations with children’s neurodevelopmental disorders is still unclear.
Objectives
To assess associations between SMM and cerebral palsy in children, overall and by major SMM subtypes.
Study design
Longitudinal cohort study of all live births in the province of Ontario, Canada, between 2003 and 2019 followed up through 2020 (n=2,136,816), under a single-payer health care system. SMM (n=41,396) was identified from inpatient or emergency department diagnoses during the index pregnancy or postpartum (20 weeks gestation to 42 days postpartum) based on validated algorithms according to diagnostic and procedure codes. SMM was categorized into severe hypertensive disorders of pregnancy (severe pre-eclampsia, HELLP syndrome, and eclampsia combined), severe hemorrhage (e.g., antepartum or postpartum hemorrhage with coagulation defect, red cell transfusion, procedures to the uterus, or hysterectomy), sepsis (puerperal sepsis or septicemia during labor), and other SMMs (e.g., admission to intensive care, shock). Cerebral palsy in offspring was defined as a single inpatient or 2 or more outpatient diagnoses at least two weeks apart between birth and the end of follow-up (age 1-17 years). Associations were estimated using Poisson regression models.
Results
Of 2,136,816 children included in this study (mean [SD] gestational age, 38.9 [1.8] weeks; 1,074,548 males [51.3%]), 41,396 (2.0%) were exposed to SMM. In a median follow-up of 9.5 years (IQR 5.2-13.7), 5,352 children were diagnosed with CP (0.3%), of which 272 CP cases (0.7%) were exposed to SMM. The average annual CP incidence was 7.5 per 10,000 child-years in those exposed to SMM and 2.5 per 10,000 in those unexposed. Children of mothers with SMM had an increased risk of CP (rate ratio (RR): 2.71 (95% confidence interval (CI): (2.39-3.06)) after adjusting for maternal sociodemographic and clinical characteristics. All SMM subtypes considered were associated with increased risks of CP, with the strongest associations observed for severe hypertension disorders (adjusted RR: 3.29 (2.44-4.33). Other SMM subtypes also showed similarly increased risks (adjusted RR for sepsis 2.45 (1.86, 3.15); severe hemorrhage 2.44 (1.89, 3.09); other SMM subtypes (2.81 (2.30-3.39)).
Conclusion
In this population-based study of over 2 million births, severe maternal morbidity was associated with increased risk of cerebral palsy. This risk was observed across major severe morbidity subtypes, including hypertensive disorders, hemorrhage, and sepsis. These findings highlight the potential benefits of optimizing maternal health and illustrate potential long-term adverse consequences of SMM in offspring. Children of mothers who experience severe or life-threatening events during the perinatal period may benefit from enhanced surveillance for early CP symptoms.