Nazarpour Sima, Ramezani Tehrani Fahimeh, Rahmati Maryam, Amiri Mina, Azizi Fereidoun
Department of Midwifery, Varamin-Pishva Branch, Islamic Azad University, Tehran, Iran.
Reproductive Endocrinology Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, 24 Parvaneh, Yaman Street, Velenjak, P.O. Box:19395-4763, Tehran, 1985717413, Islamic Republic of Iran.
Arch Gynecol Obstet. 2022 Apr;305(4):903-911. doi: 10.1007/s00404-021-06226-0. Epub 2021 Sep 5.
There are conflicting results about the effects of maternal hypothyroidism (IMH) on adverse pregnancy outcomes. This study aimed to investigate the relationship between IMH identified in the first trimester of gestation and adverse pregnancy outcomes.
In this prospective cohort study, we used data from the Tehran Thyroid and Pregnancy study (TTPs). To diagnose IMH, we considered a threshold of 2.04 for FTI, which was based on the 10th percentile of this marker identified in the 1st trimesters. A generalized linear regression (GLM) model adjusted for the gravidity, urine iodine, and TPOAb status was applied to assess the effects of IMH on adverse pregnancy outcomes, compared to the controls group.
Penalized logistic regression analysis indicated that the adjusted odds ratio (aOR) of Preterm premature rupture of the membranes (PPROM) in women with IMH was 5.43-folder higher than euthyroid group [aOR 5.43, 95% CI (1.40, 21.1), p = 0.01]. Besides, the adjusted odds ratio of low birth weight (LBW) in the IMH group was 2.53-folder higher than the healthy group [aOR 2.53, 95% CI (1.01, 6.33), p = 0.047]. Furthermore, the results of the GLM adjusted model revealed that the mean of neonatal head circumference and weight in the IMH group was around 0.43 cm (95% CI - 0.80, - 0.07, p = 0.02) and 145.4 g (95% CI - 242.6, - 48.1, p = 0.003) lower than euthyroid group, respectively.
This study demonstrated that women with IMH identified in early pregnancy have a higher odds ratio for developing some adverse pregnancy outcomes, including PPROM and LBW compared to their euthyroid counterparts. Also, the neonatal head circumference and weight in the IMH group were lower than in the euthyroid group.
关于孕期母体甲状腺功能减退（IMH）对不良妊娠结局的影响，存在相互矛盾的结果。本研究旨在调查妊娠早期确诊的IMH与不良妊娠结局之间的关系。
在这项前瞻性队列研究中，我们使用了德黑兰甲状腺与妊娠研究（TTPs）的数据。为诊断IMH，我们将FTI的阈值设定为2.04，该阈值基于孕早期该指标的第10百分位数。与对照组相比，应用调整了妊娠次数、尿碘和TPOAb状态的广义线性回归（GLM）模型来评估IMH对不良妊娠结局的影响。
惩罚逻辑回归分析表明，IMH女性发生胎膜早破（PPROM）的调整优势比（aOR）比甲状腺功能正常组高5.43倍[aOR 5.43，95%可信区间（1.40，21.1），p = 0.01]。此外，IMH组低出生体重（LBW）的调整优势比比健康组高2.53倍[aOR 2.53，95%可信区间（1.01，6.33），p = 0.047]。此外，GLM调整模型的结果显示，IMH组新生儿头围和体重的平均值分别比甲状腺功能正常组低约0.43 cm（95%可信区间 -0.80，-0.07，p = 0.02）和145.4 g（95%可信区间 -242.6，-48.1，p = 0.003）。
本研究表明，与甲状腺功能正常的女性相比，孕早期确诊为IMH的女性发生某些不良妊娠结局（包括PPROM和LBW）的优势比更高。此外，IMH组新生儿的头围和体重低于甲状腺功能正常组。
