Bibian van der Voorn

42 CHAPTER 3 TABLE 3. Associations of neonatal hair GC concentrations directly postpartumwith perinatal and maternal factors β (95%CI) P value Perinatal factors Gestational age Cortisol 0.07 (0.04 to 0.10) <0.001 Cortisone 0.04 (0.01 to 0.06) 0.004 Gestational age (only term pregnancies) Cortisol 0.11 (0.07 to 0.16) <0.001 Cortisone 0.04 (-0.001 to 0.08) 0.06 Birth weight (kg) Cortisol 0.09 (-0.003 to 0.17) 0.06 Cortisone 0.10 (0.03 to 0.17) 0.008 Birth weight (SD) Cortisol 0.01 (-0.05 to 0.06) 0.79 Cortisone 0.03 (-0.02 to 0.07) 0.23 Male sex Cortisol 0.10 (-0.02 to 0.21) 0.09 Cortisone 0.08 (-0.01 to 0.18) 0.07 Delivery via caesarian section Cortisol -0.14 (-0.26 to -0.03) 0.015 Cortisone -0.14 (-0.24 to -0.05) 0.003 Perinatal infection (≥7 days antibiotics) Cortisol 0.17 (0.06 to 0.29) 0.003 Cortisone 0.22 (0.13 to 0.31) <0.001 Respiratory problems Cortisol -0.07 (-0.28 to 0.13) 0.47 Cortisone -0.06 (-0.22 to 0.11) 0.52 Maternal factors Age Cortisol -0.01 (-0.02 to 0.01) 0.31 Cortisone 0.00 (-0.01 to 0.01) 0.82 Ethnicity Cortisol -0.04 (-0.15 to 0.08) 0.55 Cortisone -0.09 (-0.16 to 0.01) 0.07 Maternal smoking Cortisol -0.09 (-0.18 to 0.003) 0.06 Cortisone -0.09 (-0.43 to 0.26) 0.62 Parity Cortisol -0.26 (-0.36 to -0.16) <0.001 Cortisone -0.07 (-0.17 to 0.02) 0.12 Hypertensive disorders Cortisol -0.02 (-0.25 to 0.21) 0.85 Cortisone -0.15 (-0.33 to 0.04) 0.12 Values represent log-transformed β (95% confidence interval) as calculated with linear regression A B 250 275 300 325 350 0 250 500 750 1000 1250 1500 Postmenstrual age (days) Cortisol concentration (pg/mg) 250 275 300 325 350 0 100 200 300 400 500 600 Postmenstrual age (days) Cortisone concentration (pg/mg) FIGURE 1. Neonatal hair cortisol (A) and cortisone (B) levels measured directly postpartum ( ) and at the OPV ( )