ECE2015 Eposter Presentations Thyroid (non-cancer) (160 abstracts)
Reference values of TSH, FT4 and FT3 in a cohort of pregnant women in the north of Spain
David Ruiz Ochoa 1 , María Piedra León 2 , María del Carmen Baamonde Calzada 1 , Fátima Mateos García 2 , Azucena Setién Rodriguez 3 , Cristina Temprano Marañon 3 , Laura Gutierrez Chicote 4 , Raquel Zubeldia Valdés 3 , Rosa Nuria Secadas López 1 , Sonia Ojugas Zabala 3 , Mercedes Álvarez del Campo 3 , Aurora Otero García 3 , Iñigo Tejado Elviro 1 & Jose Antonio Amado Señaris 2
1Sierrallana Hospital, Cantabria, Spain; 2Marques de Valdecilla Universitary Hospital, Cantabria, Spain; 3Department of Family Medicine, Health Care Center Area IV, Cantabria, Spain; 4Department of Family Medicine, Health Care Center Area III, Cantabria, Spain.
Introduction: As soon as pregnancy is established, various physiological changes occur in maternal thyroid economy. Due to that, the reference limits of thyroid parameters used for the general population are no longer valid to diagnosis thyroid dysfunction during pregnancy.
Methods: We included 266 pregnant women, with no thyroid disorders and resident in Cantabria, a region in northern Spain. They were questioned about iodized salt and iodine supplements intake and blood samples for TSH, FT4 and FT3 were obtained in the first and third trimester of gestation and for TPO abs and Tg abs in the first trimester.
Results: Eighteen patients (6.76%) were TPO abs or Tg abs positive. Iodized salt was consumed by 39.8% in the first trimester and by 83.5% in the third (P<0.01) and iodine supplement by 70.7% in the first and 91.2% in the third (P<0.01). Reference values, expressed as median and 2.5 and 97.5 percentiles were: TSH 1.67 μUI/ml (0.27–4.16), FT4 1.06 ng/dl (0.86–1.31), FT3 2.97 pg/ml (2.42-3.65) in the first trimester and TSH 1.92 μUI/ml (0.57–4.01), FT4 0.89 ng/dl (0.70–1.08), FT3 2.85 pg/ml (2.24–3.51) in the third trimester. If we exclude TPO abs or Tg abs positive women from the analysis, reference values were: TSH 1.63 μUI/ml (0.27–4.13), FT4 1.06 ng/dl (0.86–1.31), FT3 2.97 pg/ml (2.42–3.64) in the first trimester and TSH 1.92 μUI/ml (0.65–3.95), FT4 0.88 ng/dl (0.7–1.07), FT3 2.85 pg/ml (2.27–3.53) in the third trimester. Difference between the first and third trimester were significant for TSH, FT4 and FT3 in both groups. The small group of women with positive TPO abs or Tg abs, presented a higher TSH in the first trimester compared with women without antibodies: TSH 2.23 μUI/ml vs 1.63 μUI/ml (P=0.031). No significant difference was found for TSH, FT4 or FT3 in relation to the consumption of iodized salt or iodine supplement, except a significantly higher FT3 in the third trimester between women who take iodine supplements compared to women who did not (P=0.045).
Conclusions: Method-and gestation-specific reference ranges are needed to avoid misdiagnosis of thyroid function during pregnancy. Pregnant women with positive TPO abs or Tg abs show higher levels of TSH in the first trimester compared with women without antibodies.
Article tools
My recent searches
My recently viewed abstracts
Authors
Endocrine Abstracts
ISSN 1470-3947 (print) | ISSN 1479-6848 (online)
© Bioscientifica 2024 |
Privacy policy |
Cookie settings
BiosciAbstracts
Bioscientifica Abstracts is the gateway to a series of products that provide a permanent, citable record of abstracts for biomedical and life science conferences.
Find out more