The incidence of gestational hyperthyroidism and postpartum thyroiditis in treated patients with Graves' disease
ABSTRACT Graves' disease (GD) is one of the most common thyroid diseases that cause hyperthyroidism. Gestational transient thyrotoxicosis (GTT) is nonautoimmune hyperthyroidism that occurs in women with a normal pregnancy. Postpartum transient thyroiditis (PTT) is a destructive thyroiditis induced by autoimmune mechanism in the postpartum period. Hyperthyroidism due to GD usually tends to improve during the course of gestation and exacerbate after delivery. When the patient with treated GD presents with thyrotoxicosis in the early pregnancy or in the postpartum period, differential diagnosis of exacerbation of GD with GTT or PTT is important because the latter disorders are fundamentally transient. To evaluate the incidence of GTT and PTT in a GD population, we investigated the thyroid functions, thyrotropin receptor antibodies (TRAb), and human chorionic gonadotropin (hCG) during pregnancy and for 1 year after delivery for 39 pregnancies in 34 women with GD. The incidence of GTT was 26% (10/39) of pregnancies. The peak value of hCG in the GTT group ([23.7 +/- 14.5] x 10(4) IU/mL, n = 9) was significantly higher than that in the non-GTT group ([13.3 +/- 4.7] x 10(4) IU/mL, n = 19). The incidence of PTT was 44% (17/39) of deliveries. The free triiodothyronine (FT(3))/free thyroxine (FT(4)) ratio of the exacerbation group of GD (3.1 +/- 1.0, n = 10) at the time of thyrotoxicosis after delivery was significantly higher than that of the PTT group (2.5 +/- 0.4, n = 16). The peak TRAb value of the exacerbation group of GD (72.5 +/- 121.7 IU/L, n = 10) at the time of thyrotoxicosis after delivery was also significantly higher than that of the PTT group (1.4 +/- 0.8 IU/L, n = 16). In conclusion, the high peak value of hCG is valuable for suspecting GTT, and the high FT(3)/FT(4) ratio is valuable for suspecting recurrence in the patients with GD. In both situations, changes of TRAb were also valuable in differentiating the recurrence of GD from GTT or PTT.
SourceAvailable from: John H Lazarus[Show abstract] [Hide abstract]
ABSTRACT: Risks to mother, fetus and neonate from untreated Graves' hyperthyroidism during gestation are compelling reasons for recommending pre-conception counselling. Pre-conception counselling should include discussion as to the optimum treatment of Graves' hyperthyroidism in women wishing to become pregnant. Thyrotropin receptor antibodies remain elevated following radioiodine therapy, so medical or surgical treatment may be preferred to avoid fetal or neonatal hyperthyroidism. A TSH level <2.5 mIU/l must be achieved in women receiving LT4 before conception. The patient should be reassured that both she and the fetus can be maintained in a euthyroid state and that neonatal hyperthyroidism can be readily managed with a good outcome. The risks of antithyroid drug therapy during gestation should be fully discussed with emphasis on the very low risk (although real) of liver disease with propylthiouracil treatment and embryopathy with methimazole or carbimazole therapy. While propylthiouracil is the preferred drug for the first trimester, if it is not available other thionamides may be given. Breast-feeding while on antithyroid drugs is not contraindicated provided the dose of drug is low. The patient should also be advised of the importance of thyroid monitoring in the post-partum period.04/2012; 1(1):24-29. DOI:10.1159/000336102
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ABSTRACT: The incidence of postpartum thyrotoxicosis (PT) in Graves disease (GD) patients treated with antithyroid drugs (ATDs) is higher than in the general population, but the incidence of PT among GD patients who had been treated with radioiodine (RI) or by subtotal thyroidectomy before their pregnancy is not well known. We reviewed the cases of women with GD who had become pregnant, and we selected the 188 women who had undergone RI therapy before the pregnancy and the 148 women who had undergone subtotal thyroidectomy for GD before the pregnancy as the subjects of this study. The ATD subjects were 107 women with GD who had become pregnant after being treated with ATDs alone before their pregnancy and were in remission before and throughout the pregnancy. The overall incidence of PT was 2.1% (4/188) in the RI group, 23.6% (35/148) in the subtotal thyroidectomy group, and 55.1% (59/107) in the ATD group. There were no cases of permanent thyrotoxicosis in the RI group. The incidence of PT among women with GD who have undergone RI therapy before their pregnancy was significantly low compared to thyroidectomy group and ATD group. This finding is interesting because the incidence of PT in the RI group was lower than subtotal thyroidectomy group even though thyroid volume had been greatly reduced by thyroidectomy. RI treatment is recommended in the choice of treatment for childbearing-age women as regards the risk of postpartum recurrence.Clinical nuclear medicine 02/2014; 39(4). DOI:10.1097/RLU.0000000000000386 · 2.86 Impact Factor
Article: Thyrotoxicosis of Pregnancy[Show abstract] [Hide abstract]
ABSTRACT: Thyrotoxicosis presenting during pregnancy is a common clinical problem and can be challenging to differentiate between physiologic patterns of thyroid dysfunction during gestation and intrinsic hyperthyroidism. This review provides a summary of the differential diagnosis, clinical presentation, diagnostic options, potential adverse effects of maternal thyrotoxicosis to the fetus, and treatment recommendations for thyrotoxicosis arising in pregnancy.12/2014; 1(4). DOI:10.1016/j.jcte.2014.07.008