(225) Is a refractory headache with preeclampsia under 34 weeks associated with high-grade maternal vascular malperfusion?

Objective: An unexplained, persistent headache (PH) refractory to medication is a disease-defining characteristic of preeclampsia (PreE) with severe features (SF), requiring delivery regardless of gestational age (GA). High-grade maternal vascular malperfusion (HG-MVM) has been reported in ~95% of cases delivered with very preterm PreE, with its absence suggesting an alternate headache etiology. We sought to assess the prevalence of placental HG-MVM in cases delivered < 34 weeks for a PH associated with PreE, and correlate cases by MVM status with objective clinical values.

Study Design: All placental pathology reports from 2021 and 2022 at our tertiary center were reviewed. 52 cases delivered for PreE with a PH < 34 weeks GA were identified. Two pathologists analyzed placenta histology and noted specific MVM lesions. A score of low or HG MVM was assigned based on lesion frequency from a previously published scale, and correlated with maternal, neonatal and placental demographic values relevant to PreE. Tests of normality, descriptive statistics, and appropriate comparisons via chi-squared or t-test were performed.

Results: HG-MVM was found in 23/52 (44.2%) of cases. Cases with HG-MVM had a significantly lower birth weight percentile (40.4% vs 73.0%) and placental weight percentile (10.8% vs 64.1%), with a higher prevalence of nephrotic range proteinuria (30.4% vs 3.4%), and protein:creatinine ratio [0.5(3.6) vs 0.3(0.8) mg/dL]. Maternal serum values were similar but limited by the absence of abnormal values. A summary of results is provided (Table 1).

Conclusion: Placental HG-MVM prevalence was only 44.2% in this case series, suggesting that most persistent headaches prompting delivery were due to an etiology other than PreE with SF (i.e., migraines). HG-MVM appears likely when objective clinical findings consistent with PreE are seen, and less likely when absent. Placental weight, which is correlated with volumetric measurements on ultrasound, may be particularly informative. This information is useful in considering additional workup or pursing delivery for a refractory headache with known or suspected PreE.