Maternal Smoking Leads to Increased Cord Serum IgG3

Abstract
IgG subclass levels in cord serum of unselected European newborns were studied in relation to parental smoking. Cord IgG3 was significantly (P < 0.01) higher in newborns of smoking mothers (n = 18; geom.mean = 87.0%) compared to those of non-smoking mothers (n = 66; geom.mem = 61.0%). Maternal smoking did not influence (P > 0.10) cord IgG2 or cord IgG4. Paternal smoking did not affect any of the three immunoglobulins in cord serum (P > 0.10). These data suggest that tobacco smoking affects IgG3 synthesis in some direct or indirect way.