Cord blood thyrotrophin and foetal presentation at delivery in singleton pregnancies

Cord blood thyrotrophin (TSH) levels of 134 patients with singleton pregnancies and breech presentation at delivery were compared with those of cephalic-presenting controls matched for mode of delivery, the presence of labour, parity, and the date of delivery. Infants delivered by vaginal breech delivery were found to have a higher incidence of elevated cord blood TSH level than either cephalic-presenting infants or breech-presenting infants delivered by Caesarean section. We conclude that vaginal breech delivery can be associated with false positive congenital hypothyroidism screening.