Maternal thyroid function test level during the first trimester of pregnancy at a center Yazd, Iran: A cross-sectional study

• Published in: International Journal of Reproductive BioMedicine 2021-03, Vol.19 (3), p.255-260
• Main Authors: Gholami, Somaye, Namiranian, Nasim, Shukohifar, Marzieh, Kalantari, Foroozandeh, Azizi, Reyhaneh
• Format: Article
• Language: English
• Subjects: Cross-sectional studies; first pregnancy trimester, thyrotropin, thyroxine, triiodothyronine; Hormones; Original; Pregnancy; Thyroid gland
• ISSN: 2476-4108; 2476-3772
• DOI: 10.18502/ijrm.v19i3.8573

Thyroid dysfunction is associated with negative pregnancy outcomes. There is a lack of reliable information on thyroid hormones in Iranian pregnant women, especially in Yazd. To determine the safe thyroid hormone levels in women of Yazd and also the first trimester-specific reference ranges for serum thyroid-stimulating hormone (TSH), thyroxine (T4), and triiodothyronine (T3). In this cross-sectional study, the serum of 1,148 women in the first trimester of pregnancy was analyzed. Thyroid function tests (TSH, T4, T3) were measured through radioimmunoassay (RIA) [immunoradiometric (IRMA) for TSH]. The study was conducted in Yazd, from September 2018 to November 2019. Reference intervals were defined as the 5 , 50 , and 95 percentiles. The mean age of the participants was 28.78 ( 5.86 yr) (range: 15-45 yr). The thyroid hormones reference intervals in the first trimester were TSH (0.2-3.8 mIU/l), T4 (7.45-12.75, g/dl), and T3 (100-217 ng/dl). The results of the present study determined a local thyroid function measurement in the first trimester of pregnancy at a center of Yazd, Iran. This could facilitate the decision-making of maternal TSH level during the first trimester of pregnancy.