Impact of hormone replacement therapy on serum thyroid-stimulating hormone: a retrospective analysis
Pietro Molinaro1, Livia Pellegrini2, Giulia Mariani2
1IVIRMA Global Research Alliance, IVI Roma, Rome, Italy.; University of Valencia, Valencia, Spain.
Research Question:
What is the impact of hormone replacement therapy (HRT) on serum thyroid-stimulating hormone (TSH) during endometrial preparation for single-embryo transfer (SET)?
Design:
This retrospective cohort study included 516 women (≤49 years) who underwent SET with either autologous or donor oocytes, between January 2022 and January 2023 at IVI Rome. TSH was measured at baseline (T0), during endometrial thickness assessment (T1), on embryo transfer day (T2), and at the pregnancy test (T3). TSH >2.5 mU/l was treated with levothyroxine. HRT consisted of oral estradiol valerate (6 mg/day) followed by vaginal progesterone (800 mg/day).
Results:
TSH significantly increased at T1 and T3 compared to T0 (TSH0 1.67 mU/l, 95%CI 1.59-1.74; TSH1 1.93 mU/l, 95%CI 1.83-2.04, p < 0.001; TSH3 2.08 mU/l, 95%CI 1.97-2.18, p < 0.001). Univariate analysis showed that patients with a TSH < 2.5 mU/l at T3 had higher miscarriage rate (15.2%, 95%CI 10.8-20.6 vs 29.7%, 95%CI 19.7-41.4; p = 0.01) and lower ongoing pregnancy (65.8%, 95%CI 60-71.3 vs 49.5%, 95%CI 39.5-59.5; p = 0.005) and live birth rates (62.5%, 95%CI 56.3-68.3 vs 47.5%, 95%CI 37.3-57.8; p = 0.01). Multivariate analysis showed no significant association between TSH >2.5 mU/l and pregnancy (aOR 0.64, 95%CI 0.36-1.14, p=0.13) or miscarriage (aOR 1.78, 95%CI 0.87-3.66, p = 0.11), while negative association was observed between TSH >2.5 mU/l and live birth (aOR 0.54, 95%CI 0.32-0.92, p = 0.02).
Conclusions:
HRT significantly increased TSH concentrations. Additionally, a TSH >2.5 mU/l did not correlate with miscarriage, but it was significantly associated with lower live birth rates. Further studies are needed to clarify HRT's impact on thyroid function and reproductive outcomes.
Related Concept Videos
01:20Synthesis and Regulation of Thyroid Hormones
Upon reaching the thyroid gland, TSH stimulates the follicular cells' active uptake of iodide ions from the blood. The ions diffuse to the apical surface of the cells and are oxidized to iodine. The...
01:18Functions of Thyroid Hormones
TH is indispensable for the normal development and maturation of the skeletal, muscular, and nervous systems during fetal and childhood growth. It facilitates bone mineral turnover and regulates protein synthesis in developing tissues, contributing significantly to overall growth and...
01:22Target Cell Response to Hormones
Notably, the cellular response can be regulated by altering the number of receptors expressed in the cell. For example, prolonged exposure to elevated hormone levels results in a gradual decline or down-regulation in the number of receptors for that specific hormone on the cell surface. Conversely, in response to low hormone levels, cells may use up-regulation, producing an...
01:17Hormones and Bone Tissue
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...
01:19Regulation of Hormone Secretion
Humoral...
01:27Major Hormones and Their Functions
Oxytocin, produced in the hypothalamus and released by the pituitary gland, plays a role in social bonding, childbirth, and...