Normal pregnancy thyroid function

Baseline tests CBC, hepatic function, pregnancy test, TSH, renal function, uric acid, HCVRNA level. Exclusions to treatment platelet count <90,000 cells/mm (as low as 75,000 cells/mm in patients with cirrhosis) absolute neutrophil count < 1,500 cells/mm serum creatinine concentration > 1.5 X upperlimit of normal abnormal thyroid function... 

Neonatal goiter caused by the use of potassium iodine as an expectorant during pregnancy has been reported (67). The neonate, a girl, had acute hypothyroidism, with myxedema and respiratory distress. She was given levothyroxine for 6 months, with complete normalization of thyroid function. 

Electrolytes, renal and thyroid function, FSH, LH, and testosterone are within normal limits. Elevated prolactin at 115 ng/mL (115 mcg/L). Pregnancy test is negative. 

There is no final consensus on whether normal use of lithium, without any episode of toxicity (the vast majority of patients), may result in permanent renal impairment. Polyuria occurs in 20-40% and is due to inhibition of antidiuretic hormone (ADH) by lithium. It usually resolves on cessation of lithium as do any effects on glomerular function. Interference with thyroid function is due to inhibition of the action of thyroid stimulating hormone (TSH) and is easily managed by administration of thyroxine. Lithium is contraindicated during pregnancy (major vessel anomalies in fetus) and breastfeeding. 

Table 42.3 Regulation of thyroid function in normal pregnancy...

The fetus is totally dependent on maternal iodine supply throughout gestation, and on thyroxine supply during the first trimester of pregnancy for normal neurological development and nervous system maturation. It is therefore imperative that TH synthesis is adequate and is met with the appropriate iodine intake. Accordingly, it is important to know the trimester-specific reference intervals for THs and other thyroid functions in pregnancy. 

When neurological results were related to early-pregnancy maternal thyroid function, it was seen that all 11 ADHD+ children were born to the ID area mothers whose thyroid function proved more heavily compromised than that of the 5 ADHD— mothers, and that 7/8 (87.5%) of the ID area mothers who experienced thyroid failure generated ADHD+ children. It is worth noting, however, that individual TSH levels fell consistently within the normal range in all but two of these women,... 

Exceptions to this recommendation are women with known thyroid disease, who should be individually managed to ensure normal thyroid function during pregnancy, or women with high iodine intake from other sources. 

I certainly agree with you that 1-T4 administration should not be recommended in all pregnancies. In terms of suppression of the goitrogenic stimulus, both KI and KI + 1-T4 had the same effects. However, in terms of thyroid function parameters, the results were not comparable while KI alone only stabilized increased Tg, KI + 1-T4 was accompanied by a normalization of thyroglobulin levels. The same observation was made for other... 

The only useful contribution of endocrine studies to diagnosis has been in the condition dystrophia myotonica, with its 80% incidence of eventual primary testicular atrophy in males. Many workers (Cl, Dl, G7, K15) have reported the urinary excretion of 17-ketosteroids in this condition to be subnormal in males, and even in females to be in the low normal range. Recent thorough investigations, however (B22, D18), have disclosed that, apart from an unexplained frequently low basal metabolic rate and the consequences of eventual testicular atrophy, there seems to be no reason to suppose that adrenal cortical, thyroidal, ovarian, and pituitary functions are other than normal in dystrophia myotonica. A majority of males examined had been fertile, and most women had brought one or more normal full-term pregnancies to spontaneous delivery. 

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