Clinical Research Directory

Levothyroxine Treatment on Cardiac Function in Children With Subclinical Hypothyroidism

This study aims to evaluate the effect of the treatment with levothyroxine on cardiac function in children with subclinical hypothyroidism.

Thyroid Hormone Replacement After Coronary Artery Bypass Grafting for Patients With Subclinical Hypothyroidism

The goal of this clinical trial is to find out whether levothyroxine reduces complications and improves the prognosis of patients with subclinical hypothyroidism (SCH) undergoing coronary artery bypass grafting (CABG). The main questions this study aims to answer are: • Does levothyroxine reduce major adverse cardiovascular events (MACE), including cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, and new arrhythmias, in SCH patients undergoing CABG? Researchers will compare patients who take levothyroxine with those who do not. Participants will: * Be randomly assigned to either receive levothyroxine or not * Start the medication one day before surgery if assigned to the treatment group. * Have regular follow-up visits to check thyroid function and cardiovascular events for up to five years after surgery.

Levothyroxine Treatment and IVF Outcomes in Women With Subclinical Hypothyroidism: A Target Trial Emulation

Subclinical hypothyroidism (SCH) is defined by elevated thyroid-stimulating hormone (TSH) with normal free thyroxine (fT4) levels. It affects approximately 5-7% of women of reproductive age and may negatively influence outcomes of assisted reproductive technology (ART). During controlled ovarian stimulation, rising estradiol increases thyroxine-binding globulin and thyroid hormone requirements. These physiological changes, combined with increased metabolic demand in early pregnancy, may worsen SCH and contribute to adverse outcomes such as miscarriage, preterm birth, and hypertensive disorders of pregnancy. Although levothyroxine (LT4) is routinely used to treat overt hypothyroidism, evidence for its benefit in SCH, especially among infertile women undergoing In Vitro Fertilization (IVF) or Intra-Cytoplasmic Sperm Injection (ICSI) with frozen embryo transfer (FET), remains inconclusive. Some trials and meta-analyses have shown reductions in miscarriage and neonatal mortality, while others have found no improvement in ART or obstetric outcomes. This study aims to evaluate the effectiveness of levothyroxine therapy on IVF/FET outcomes and subsequent pregnancy results in women with subclinical hypothyroidism and infertility. This retrospective cohort study will emulate the target trial to evaluate whether LT4 treatment, titrated to achieve a pre-transfer TSH \< 2.5 mIU/L, improves implantation, live birth, and obstetric outcomes compared with expectant management.

Impact of Subclinical Hypothyroidism on Liver Enzymes and Lipid Profile

the goal of the randomized controlled observational study is to observe the effect of subclinical hypothyroidism on liver enzymes and lipid profile

Best Treatment for Women With Both (Polycystic Ovary Syndrome) PCOS and Subclinical Hypothyroidism

The goal of this randomized controlled trial is to compare letrozole alone versus letrozole plus levothyroxine for ovulation induction in infertile women with both PCOS and subclinical hypothyroidism. The main questions it aims to answer are: Is letrozole plus levothyroxine superior to letrozole alone in achieving ovulation in these patients? Does combining levothyroxine with letrozole lead to higher pregnancy and live birth rates compared to letrozole alone? Participants will be randomized into two groups: Group 1 will receive letrozole only, starting at 2.5 mg daily from day 3 to 7 of the menstrual cycle. The dose will be increased up to 7.5 mg if no ovulation occurs, for a maximum treatment period of 6 months or until pregnancy is achieved. Group 2 will receive letrozole at the same doses as group 1 plus 25 mcg levothyroxine daily.