Modeling fetal cortical development by quantile regression for gestational age and head circumference: a prospective cross sectional study

Objectives: To develop charts for fetal brain cortical structures following a proposed standardized methodology and using quantile regression. Methods: Prospective cross-sectional study including 344 low-risk singleton pregnancies between 19 and 34 weeks of gestation. The depth of Sylvian (SF), Parieto-occipital (POF) and calcarine fissures (CF) were measured on ultrasound images using a standardized technique and their changes were evaluated by quantile regression as a function of gestational age (GA) interval or head circumference (HC). Results: The measurements of SF, POF and CF depth significantly increased with gestation. Linear models better described the changes of cortical variables with GA and HC. When the fit of sulci depth with GA and HC were compared, a close relationship was highlighted for the latter variable. Conclusions: We provided prospective charts of fetal cortical development using quantile regression and following a strict standardized methodology These new charts may help in better identifying cases at higher risk of abnormal cortical neurodevelopment