The median AF levels of IGFBP-4 and lipocalin-2 were significantly higher and those of VEGFR-1 were significantly lower in women who had SPTD at < 34 weeks than in those who delivered at ≥ 34 weeks (P < 0.05 for each, Table 2). The gene discussed is IGFBP4; the disease is atrial fibrillation.