Serum neurofilament light chain increases in healthy postpartum: is it subclinical brain damage or neuroplasticity?

Background Elevated serum neurofilament light chain (sNfL) levels occur postpartum in women with pre-eclampsia or multiple sclerosis (MS), though definitive central nervous system (CNS) injury remains unestablished. Data on sNfL levels in healthy women with physiological pregnancies (HWwPP) are lacking, whereas numerous MRI and histological studies have demonstrated pregnancy-induced neuroplasticity. Methods We collected blood samples from 61 HHwPP at four peripartum time points (−1, +1, +2-5, +6-10 days), including nulliparous, primiparous, and multiparous women. Two additional control groups (19 healthy women at 20-180 days postpartum; 43 healthy women remote from delivery) were studied. Serum levels of NfL, Glial Fibrillary Acidic Protein (GFAP), Tubulin Associated Unit (TAU) protein, and Ubiquitin C-terminal Hydrolase L1 (UCHL1) were analyzed. Results sNfL levels doubled on postpartum day 1 (median 19.84; range 5.02-66.19) versus pre-delivery (8.86; 1.88-34.62) (p