Management of thyroid dysfunction during pregnancy and postpartum

THE ENDOCRINE SOCIETY’S CLINICAL GUIDELINES
women was clinically hyperthyroid. Thyroid
antibodies were not found in most instances. The
median birth weight of the infants of mothers who
experienced a weight loss of more than 5% of their
prepregnancy weight was lower than that of infants of
women who did not (71).
In another study 22 of 33 patients admitted with
hyperemesis (66.7%) had biochemical hyperthyroidism
(suppressed TSH or increased T 3 index or T 4
index). Hyperthyroid patients were more likely than
euthyroid patients to have abnormal electrolyte levels
[16/22 (72.7%) vs. 3/1 (27.3%), P < 0.02] or increased
liver enzyme levels [8/22 (36.4%) vs. 3/11 (27.3%)].
The severity of hyperemesis was found to vary directly
with the degree of hyperthyroidism. A predominance of
females was found among the offspring of mothers with
hyperemesis gravidarum (149).
Treatment of subclinical hyperthyroidism (TSH
below normal limits with free T 4 and total T 4 in the
normal pregnancy range) has not been found to
improve pregnancy outcome and may risk
unnecessary exposure of the fetus to ATDs (70, 71,
110, 111).
3.4. RECOMMENDATIONS
3.4.1. Thyroid function tests should be measured in
all patients with hyperemesis gravidarum (5% weight
loss, dehydration, and ketonuria). The USPSTF
recommendation level is B; evidence is poor
(GRADE 2| ) (70, 71, 152, 158).
3.4.2. Few women with hyperemesis gravidarum will
require ATD treatment. The USPSTF recommendation
level is A; evidence is good (GRADE
1| ). Overt hyperthyroidism believed due to
coincident Graves’ disease should be treated with
ATDs. The USPSTF recommendation level is B;
evidence is fair (GRADE 1| ). Gestational
hyperthyroidism with clearly elevated thyroid hormone
levels (free T 4 above the reference range or total T 4 >
150% of top normal pregnancy value and TSH < 0.1
µU/ml) and evidence of hyperthyroidism may require
treatment as long as clinically necessary. The USPSTF
recommendation level is I; evidence is poor ( )
(70, 71, 152, 158).
3.5. REMARKS
Although the data available do not prove the benefit,
many members of this committee believe that there is
significant potential benefit in performing thyroid
function testing on all pregnant women with
hyperemesis and possible hyperthyroid signs and
symptoms, and that there is likely benefit from
screening all women with gestational hyperemesis.
3.6. BIBLIOGRAPHY—ITEMS RELATED TO
RECOMMENDATIONS
Al-Yatama M, Diejomaoh M, Nandakumaran M,
Monem RA, Omu AE, Al Kandari F 2002 Hormone
profile of Kuwaiti women with hyperemesis
gravidarum. Arch Gynecol Obstet 266:218 –222
Human CG, TSH, total T 4 , and free T 4 were
measured in the serum of 55 patients with
hyperemesis gravidarum compared with a control
group of 55 women. The incidence of hyperemesis in
the maternity population was 45 per 1000 deliveries.
Total ()hCG and total T 4 and free T 4 were
significantly higher in the hyperemesis patients than
in the normal controls (P < 0.0001, P = 0.004, and
P = 0.01, respectively). TSH levels were significantly
lower in hyperemesis patients than in their normal
controls (P < 0.0001). None of the patients showed
signs of hyperthyroidism.
Goodwin TM, Montoro M, Mestman JH 1992
Transient hyperthyroidism and hyperemesis
gravidarum: clinical aspects. Am J Obstet Gynecol
167:648–652
Sixty-seven patients seen at Los Angeles County
Women’s Hospital over a 10-month period with
hyperemesis gravidarum were studied prospectively
with respect to thyroid function. Forty-four patients
(66%) had biochemical hyperthyroidism [increased
free thyroxine index (n 39) or suppressed TSH (n
40)] that was self-limited, resolving by 18 wk
gestation. Hyperthyroid patients were more likely
40