Thyroid Function in the Perinatal Period

Pickering, Donald E.

doi:10.1001/archpedi.1958.02060050620005

Cited by 13 publications

(9 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This observation has been amply confirmed (2)(3)(4)(5)(6), and increases in triiodothyronine-mI erythrocyte or resin uptake (4,(7)(8)(9) and in free thyroxine (6) have also been demonstrated. These data indicate and quantitative measurements have confirmed (5) that alterations in maximal binding capacity of thyroxine-binding serum proteins are not responsible for the neonatal hyperthyroxemia.…”

Section: Introductionmentioning

confidence: 65%

Acute release of thyrotropin in the newborn

Fisher¹,

Odell²

1969

J. Clin. Invest.

227

View full text Add to dashboard Cite

A B S T R A C T Measurements of serum thyrotropin(TSH) concentrations were conducted in maternal and fetal blood during labor and delivery and the early postnatal and neonatal periods. Mean TSH concentration was significantly higher in cord blood (9.5 AU/ml) than maternal blood (3.9 /U/ml), a finding suggesting a fetalmaternal TSH gradient at term. Serum TSH concentration in the newborn increased rapidly to mean levels of 60 AU/ml at 10 min and 86 AU/ml at 30 min of age.Between 30 min and 3-4 hr serum levels decreased rapidly, then fell more gradually to a mean concentration of 13 AU/ml at 48 hr. The half-time of the decrease in serum TSH concentration between 30 and 90 min was 77 min, a value slightly greater than the half-time of disappearance of radioiodinated TSH measured in adults. This indicates that the early high rate of TSH secretion in the newborn ceases by 30 min, and that the rapid rise and fall in serum TSH concentrations may represent release of stored pituitary TSH. A more chronic TSH hypersecretion persisted throughout the first 24-48 hr of extrauterine life. Measurements of serum PBI concentrations were conducted in a separate group of maternal and cord blood samples and in the newborn infants during the first 48 hr of extrauterine life to relate the TSH and serum hormonal iodine concentration changes. Serum protein-bound iodine (PBI) concentrations were similar in maternal and cord blood, increased significantly by 4 hr of age in the newborn, and peaked at about 24 hr, presumably in response to the TSH hypersecretion. The pattern of TSH hypersecretion was similar in infants delivered vaginally and by caesarean section. Maternal serum TSH concentrations were stable throughout the perinatal period. Warming the infants at 99-103'F during the first 3 hr of life did not prevent the early, acute release of thyrotropin. Cooling of warm infants at room temperature (72-780F) between 3 and 4 hr resulted in a decrease in mean rectal temperature of 3.3XF and produced a significant increment in serum TSH concentration. These data suggest

show abstract

Section: Introductionmentioning

confidence: 65%

Acute release of thyrotropin in the newborn

Fisher¹,

Odell²

1969

J. Clin. Invest.

227

View full text Add to dashboard Cite

show abstract

“…Thyroxine labeled with radioiodine2 was given intravenously. Beginninig one day prior to injection, methimazole (Tapazole) in 10 mg doses every 8 hours was-administered orally to each child for 10 days, to inhibit uptake of radioiodinie by the thyroid. Serunm protein-bound iodine (PBI), determined by the alkaline ash method of Barker, Humphrey and Soley (10), was estimated before and on the eighth day of the study.…”

Section: Methodsmentioning

confidence: 99%

“…Although the plasma concentration of thyroid hormone in newborn infanits is appreciably higher than in adults, in children there appears to be no significant difference (4)(5)(6)(7)(8)(9). The present study of thyroxine metabolism was designed to further define thyroid hormone metabolism in children.…”

mentioning

confidence: 98%

Rates of I131-Labeled Thyroxine Metabolism in Euthyroid Children

Haddad¹

1960

J. Clin. Invest.

View full text Add to dashboard Cite

“…3. Triiodothyronine I 131 resin uptake was meas¬ ured in 28 cord blood samples (12 premature and 16 full-term infants) and postnatal sera of 46 pre¬ mature infants (16 infants 4 to 10 days of age, eight infants 11 to 20 days, ten infants 21 to 30 days and 12 infants 31 to 60 days of age).…”

Section: Methodsmentioning

confidence: 99%