Institute for Endocrinologie, Hamburg, Germany.
Due to early demission of women soon after parturition neonatal (nn) TSH-screening of the new born becomes a problem. Therefore we investigated, whether measurements of TSH (Units per liter), free thyroxine (fT4 picogram per millilitre) and antibodies against thyroxine-peroxidase (a-TPO, Units per millilitre) in cord blood of spontaneously delivered babies at term, might be an alternative. Routine (nn) TSH-screening was recommended to be carried out on day 5 of life. Their mothers were presumed to have no thyroid disease; 27 out of a total of 144 took 200 μg iodine daily.
Although nn TSH-Screening is evaluated in one single institute in the area, the results of 4 could not be found out; cb TSH and fT4 of those whose mothers took iodine tablets, were not significantly different from those who did not (mean of total TSH 5.5 plus/minus 3.6, fT4 11.9 plus/minus 1.8); in 20 cb samples a-TPO was detected; in 12 it was below, in 8 above the limit of 35 Units per millilitre of the WHO-Standard. 10 newborns had a greater TSH than the 95th percentile of 11.7 and / or a lower fT4 of 10.1 reflecting subclinical hypothyroidism; nn TSH-screening revealed in none hypothyroidism.
The incidence of so far unknown Hashimoto`s is high. In respect to data published by Dussault and Fischer in 1999, that one third of babies of mothers with H. may develop (transient) hypothyroidism, an adequate thyroid control of such newborns should be prompted. Determination of cb thyroid hormones seems to be an alternative to nn TSH-Screening where difficulties may arise to perform it; detection of metabolic disorders is however not possible.