Smoking during pregnancy, neonatal infection and hypoglycemia are risk factors for perinatal stroke, according to a new study from New South Wales, Australia published in April 2023 issue of The Journal of Paediatrics and Child Health.¹

This study analysed 60 term infants with perinatal stroke reported between 2017 and 2019. Each infant was matched by gestational age and birth date with 3 healthy controls. There were 60% arterial strokes (neonatal arterial ischemic stroke [NAIS]), 35% venous strokes (neonatal hemorrhagic stroke [NHS] 30%, cerebral sinovenous thrombosis [CSVT] 3% and NHS+CSVT 2%) and 5% mixed strokes (NAIS + NHS 3% and NAIS + CSVT 2%). Out of the 60 cases included in the study, 57 were found to have multiple risk factors for perinatal stroke.

On univariate risk factor analysis, factors significantly associated with higher risk of perinatal stroke were low Apgar score (<7) at 1, 5 and 10 minutes of age; emergency cesarean section, abnormal cord blood gas, neonatal infection or sepsis, congenital heart disease, neonatal hypoglycemia and resuscitation at birth.  While factors like multigravida, maternal age >35 years, history of miscarriage, stillbirth or neonatal death had lower associated risk of stroke.

On multivariate analysis, in the full multivariable logistic regression model, after adjusting for the other maternal and neonatal risk factors, the risk of perinatal stroke was markedly increased with a 1-minute Apgar score of less than 7 with odds ratio (OR) of 1.54. Other risk factors that were significantly associated with stroke were smoking during pregnancy with OR 1.48, 10-min Apgar score < 7 (OR 1.26) and hypoglycemia (OR 1.49). In the reduced model (after selection of variables), the risk of stroke was increased by 39% with a maternal history of smoking; the risk increased 61% with a 1-min Apgar score < 7, 27% with a 10-min Apgar score < 7 and 39% with neonatal infection or sepsis.

Diagnosis of perinatal stroke is often challenging because of unknown cause, non-neurological presentation and multiple risk factors. This study has established exposure to smoking during pregnancy, 10-min Apgar score < 7, neonatal infection and hypoglycemia as independent risk factors for perinatal stroke suggesting a multifactorial etiology on account of prenatal, perinatal and neonatal factors.

Reference

1. Roy B, et al. Risk factors for perinatal stroke in term infants: A case-control study in Australia. J Paediatr Child Health. 2023 Apr;59(4):673-679. doi: 10.1111/jpc.16372.