PROLACTIN, GROWTH-HORMONE AND INSULIN-LIKE GROWTH FACTOR-I IN NEWBORNCHILDREN OF SMOKING MOTHERS

OBJECTIVE Since maternal smoking causes fetal circulatory abnormalitie s, as well as disturbances of the maternal endocrine equilibrium, we m easured the PRL, hGH and insulin-like growth factor-I (IGF-I) concentr ations in the cord and venous blood of neonates of smoking mothers to determine whether or not the tobacco smoke affects the endocrine statu s of the neonate. DESIGN The above hormones were measured in the cord blood of the newborns of both smoking and non-smoking mothers. Also, P RL and hGH were determined at 24 and 72 hours after birth in newborns of both groups. PATIENTS Fifty-three newborns of smoking and 47 newbor ns of non-smoking mothers were investigated. Seventeen of the newborns of the smoking and 21 of the nonsmoking mothers were preterm. The rem ainder were full-term. MEASUREMENTS PRL was measured with a solid-phas e immunoradiometric assay, hGH with a solid-phase two-site immunoradio metric assay and IGF-I with a solid-phase radioimmunoassay after extra ction with acid-ethanol. RESULTS The median value of PRL in the 17 pre term newborns of smoking mothers was 4941 mU/l (range 1322-7230), wher eas in the 21 preterm newborns of nonsmoking mothers it was 2013 mU/l (range 243-4740) (P=0.0002). The median hGH value in the above subject s was 102.0 mU/l (range 35.2-208.4) and 59.8 mU/l (range 11.6-134.2), respectively (P=0.0039). The median IGF-I was 580.7 U/I (range 253.2-4 851.1) and 530.6 U/l (range 239.6-3591.5), respectively (P=0.429). In the 36 full-term newborns of smoking mothers the median PRL value was 5171 mU/l (range 2074-7530), whereas in the 26 full-term newborns of n on-smoking mothers it was 5081 (range 244-6540) (P=0.048). The median hGH was 69.6 mU/l (range 42.3-280.0) and 32.2 mU/l (range 6.2-200.0), respectively (P=0.0031). Also, the median IGF-I value was 926.3 U/l (r ange 348.5-5344.7) and 462.1 U/l (range 250.2-1578.7), respectively (P =0.0024). On the 3rd day the PRL in the preterm neonates of both smoki ng and non-smoking mothers showed the same 16.5% drop, and thus the di fference between the groups was maintained. A similar reduction in the hormone levels was observed in the full term neonates. CONCLUSIONS Th e findings indicate that the maternal tobacco-smoking causes disturban ces of the endocrine status of the fetus, as shown by the increased le vels of PRL, hGH and IGF-l, which are more pronounced between 30 and 3 7 weeks of gestation than at term.