title: Thyroid function in late preterm infants in relation to mode of delivery and respiratory support.
abstract: The relationship between thyroid function, mode of delivery, and illness in infants 34-36 weeks' gestation has not been well studied. We hypothesized that infants born by cesarean delivery and those with increased illness would have a reduction in thyroxine (T4) following birth. Total T4 and thyroid-stimulating hormone were obtained at birth (Time 1) and between days 2 and 5 (Time 2). The study sample included 129 infants 34-36 weeks' gestation. There were no differences in total T4 between infants born by cesarean or vaginal delivery (p=0.18), or between those requiring respiratory support compared to infants not requiring respiratory support (p=0.09). At Time 2, 93% of the study population had a total T4 below one standard error of the reference laboratory mean. In our study sample, despite many infants having a low total T4, there was no association between total T4 levels, respiratory support, or mode of delivery.
authors.forename: Renee M
authors.initials: RM
authors.lastname: Behme
authors.forename: Amy B
authors.initials: AB
authors.lastname: Mackley
authors.forename: Louis
authors.initials: L
authors.lastname: Bartoshesky
authors.forename: David A
authors.initials: DA
authors.lastname: Paul
mesh_terms: D000328:Adult; D002585:Cesarean Section; D036861:Delivery, Obstetric; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D011247:Pregnancy; D012121:Respiration, Artificial; D013961:Thyroid Gland / Q000503:physiopathology*; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood
chemical_list: D013972:Thyrotropin; D013974:Thyroxine