According to an abstract published in the Journal of Allergy and Clinical Immunology, pregnant individuals with systemic mastocytosis (SM) are more likely to develop eclampsia, but not other pregnancy complications. Findings will be presented at the upcoming 2026 American Academy of Allergy, Asthma and Immunology Annual Meeting held February 27-March 2, 2026, in Philadelphia.
Eclampsia is the occurrence of seizures in people with preeclampsia, a serious blood pressure condition that can develop during pregnancy.
“In this largest real-world study to date of SM and pregnancy, SM was associated with a decreased risk of abortive outcome but an increased risk of eclampsia,” the authors wrote.
The study included data from 307 pregnant individuals with SM and 307 pregnant controls. Cases and controls were matched for age at pregnancy and race. The investigators obtained de-identified patient information from TriNetX, a global health data network.
Read more about SM signs and symptoms
Of note, 3.3% of patients with SM and 0% of controls developed eclampsia. Furthermore, 11.1% of controls experienced abortive outcomes compared with just 4.6% of patients with SM, representing a significant risk difference of 6.5%.
The study also found that 4.6% of patients with SM and 3.3% of controls experienced preeclampsia, while 3.3% of cases and 4.2% of controls experienced gestational hypertension (high blood pressure occurring during the later part of pregnancy). Additionally, 3.3% of cases and 4.6% of controls reported preterm labor. None of these differences achieved statistical significance.
These findings do not establish a definitive causal link between SM and eclampsia. Still, they have the potential to guide clinical care by advising providers and patients on possible pregnancy complications to be aware of. With the proper monitoring and care, many individuals with SM can experience healthy, uncomplicated pregnancies.
Sign up here to get the latest news, perspectives, and information about SM sent directly to your inbox. Registration is free and only takes a minute.
