Atypical Preeclampsia before 20 Weeks of Gestation-A Systematic Review

This systematic review was conducted to gather evidence of preeclampsia occurring before the 20th week of gestation, additionally considering the role of PLGF and sFlt-1 in the development of the disease. In the three cases of preeclampsia before the 20th week of gestation presented in the authors' material, all pregnancies ended up with IUFD, and the SFlt-1/PLGF ratios were significantly elevated in all women. Eligible publications were identified with searches in the PubMed, Embase, Scopus, and Web of Science databases. No date or language restrictions were made. All original peer-reviewed scientific reports were included. A total of 30 publications were included in the final report, including case reports and case series. No other publication types regarding this issue were identified. In the literature, 34 cases of preeclampsia with onset occurring before the 20th week of gestation were identified, for a final total of 37 cases. Live births were reported in 5 cases (10.52%), and there were 9 intrauterine fetal demises (24.32%), and 23 terminations of pregnancy (62.16%). Preeclampsia before the 20th week of gestation is rare but can occur. We collected all available evidence regarding this phenomenon, with 37 cases reported worldwide. We call for large-scale cohort or register-based studies to establish revised definitions or develop new ones regarding the currently unrecognized very early onset preeclampsia.

Automated summary

This systematic review collected evidence on preeclampsia occurring before the 20th week of gestation and investigated the role of PLGF and sFlt-1 in its development. In the analyzed cases, all pregnancies with preeclampsia before the 20th week resulted in intrauterine fetal demise, and elevated SFlt-1/PLGF ratios were observed in all women. The review identified 37 reported cases worldwide, emphasizing the need for further research to establish revised definitions or new ones for this very early onset preeclampsia, which is rare but possible.