Am J Reprod Immunol. 2000 Apr;43(4):204-8.
Mild thyroid abnormalities and recurrent spontaneous abortion: diagnostic and
Vaquero E, Lazzarin N, De Carolis C, Valensise H, Moretti C, Ramanini C.
Department of Obstetric and Gynecology, University of Rome, Tor Vergata, Italy.
* Am J Reprod Immunol. 2000 Apr;43(4):202-3.
PROBLEM: The aim of this study is to evaluate the role of mild thyroid
abnormalities in recurrent spontaneous abortion, and to assess the effects of
two different therapeutical protocols. METHOD: A prospective study in the
population of recurrent aborters with mild thyroid abnormalities, evaluating the
obstetric outcome in 42 patients. Sixteen thyroid autoantibodies positive
patients were treated with thyroid replacement therapy, while 11 patients
received intravenous immunoglobulins (IVIG). Fifteen patients, characterized by
negative antithyroid antibodies, and having underlying thyroid pathology, were
treated with thyroid replacement therapy. RESULTS: Among patients with thyroid
antibodies, 6 out of the 11 pregnancies (54.5%) treated with IVIG ended in live
birth. In the thyroid supplementation group, 13 out of 16 pregnancies (81.2%)
ended in live birth. Only one pregnancy loss occurred among patients with a mild
underlying thyroid pathology treated with thyroid replacement therapy.
CONCLUSIONS: Mild thyroid abnormalities are associated with an increased rate of
miscarriage. This poor obstetrical prognosis seems to be related to an impaired
thyroid adaptation to pregnancy. Thyroid replacement therapy appears to be more
effective than IVIG in preventing a new miscarriage.
J Clin Endocrinol Metab. 2006 Jul;91(7):2587-91. Epub 2006 Apr 18.
Levothyroxine treatment in euthyroid pregnant women with autoimmune thyroid
disease: effects on obstetrical complications.
Negro R, Formoso G, Mangieri T, Pezzarossa A, Dazzi D, Hassan H.
Department of Endocrinology, Azienda Ospedaliera LE/1, P.O. "V. Fazzi", Piazza
F. Muratore, 73100 Lecce, Italy. email@example.com
* Nat Clin Pract Endocrinol Metab. 2006 Dec;2(12):664-5.
* J Clin Endocrinol Metab. 2006 Jul;91(7):2500-2.
CONTEXT: Euthyroid women with autoimmune thyroid disease show impairment of
thyroid function during gestation and seem to suffer from a higher rate of
obstetrical complications. OBJECTIVE: We sought to determine whether these women
suffer from a higher rate of obstetrical complications and whether levothyroxine
(LT(4)) treatment exerts beneficial effects. DESIGN: This was a prospective
study. SETTING: The study was conducted in the Department of Obstetrics and
Gynecology. PATIENTS: A total of 984 pregnant women were studied from November
2002 to October 2004; 11.7% were thyroid peroxidase antibody positive
(TPOAb(+)). INTERVENTION: TPOAb(+) patients were divided into two groups: group
A (n = 57) was treated with LT(4), and group B (n = 58) was not treated. The 869
TPOAb(-) patients (group C) served as a normal population control group. MAIN
OUTCOME MEASURES: Rates of obstetrical complications in treated and untreated
groups were measured. RESULTS: At baseline, TPOAb(+) had higher TSH compared
with TPOAb(-); TSH remained higher in group B compared with groups A and C
throughout gestation. Free T(4) values were lower in group B than groups A and C
after 30 wk and after parturition. Groups A and C showed a similar miscarriage
rate (3.5 and 2.4%, respectively), which was lower than group B (13.8%) [P <
0.05; relative risk (RR), 1.72; 95% confidence interval (CI), 1.13-2.25; and P <
0.01; RR = 4.95; 95% CI = 2.59-9.48, respectively]. Group B displayed a 22.4%
rate of premature deliveries, which was higher than group A (7%) (P < 0.05; RR =
1.66; 95% CI = 1.18-2.34) and group C (8.2%) (P < 0.01; RR = 12.18; 95% CI =
7.93-18.7). CONCLUSIONS: Euthyroid pregnant women who are positive for TPOAb
develop impaired thyroid function, which is associated with an increased risk of
miscarriage and premature deliveries. Substitutive treatment with LT(4) is able
to lower the chance of miscarriage and premature delivery.
J Clin Endocrinol Metab. 1994 Jul;79(1):197-204.
Risk of subclinical hypothyroidism in pregnant women with asymptomatic
autoimmune thyroid disorders.
Glinoer D, Riahi M, Grün JP, Kinthaert J.
Department of Internal Medicine, Hospital Saint-Pierre, Université Libre de
A prospective study was undertaken in 87 healthy pregnant women with thyroid
antibodies and normal thyroid function at initial presentation [asymptomatic
autoimmune thyroid disorders (AITD)]. The aims of the study were to assess
whether women with AITD constitute a group at risk of developing subclinical
hypothyroidism during pregnancy, and whether a mild thyroid function impairment
may be associated with obstetrical repercussions. The women investigated were
selected among a cohort of 1660 consecutive pregnancies on the basis of 1) no
previous history of thyroid disease, 2) euthyroidism at initial presentation,
and 3) positive thyroglobulin antibodies and/or thyroid peroxidase antibodies
(TPO-Ab). Women with AITD had a basal TSH value significantly higher, albeit
still normal, in the first trimester (1.6 vs. 0.9 mU/L; P < 0.001) than that in
women with healthy pregnancies used as controls. Despite a 60% average reduction
in TPO-Ab titers during gestation, serum TSH remained higher in women with AITD
than in controls throughout gestation: at delivery, 40% of the cases had serum
TSH levels above 3 mU/L, and 16% had serum TSH levels above 4 mU/L. A TRH test
carried out in the days after parturition showed an exaggerated response in 50%
of the cases. Furthermore, free T4 concentrations were in the range of
hypothyroid values in 42% of the women. Obstetrical repercussions were observed,
namely increased rates of spontaneous miscarriage and premature deliveries. In
conclusion, women with asymptomatic AITD who are euthyroid in early pregnancy
carry a significant risk of developing hypothyroidism progressively during
gestation, despite a marked reduction in antibody titers. Hypothyroidism results
from the reduced ability of the gland to adjust to the changes in thyroidal
economy associated with pregnancy. At the individual level, progression to
subclinical hypothyroidism was broadly predictable on the basis of serum TSH
levels and TPO-Ab titers in the first trimester. Hence, these parameters provide
useful markers to identify women who carry a higher risk, allowing for a close
monitoring of thyroid function during pregnancy and the administration of L-T4
in specific cases. Taken together with the known incidences of postpartum
thyroiditis and hypothyroidism in women with AITD, the present observations in
our opinion justify systematic screening of thyroid autoimmunity during pregnancy.
PMID: 8027226 [PubMed - indexed for MEDLINE]