Levothyroxine for women with mild (subclinical) hypothyroidism having IVF/ICSI and frozen embryo transfer
Effectiveness of Levothyroxine Treatment on In Vitro Fertilization and Pregnancy Outcome in Women With Subclinical Hypothyroidism and Infertility: A Target Trial Emulation
This project will try giving low‑dose levothyroxine to women with subclinical hypothyroidism undergoing IVF/ICSI with frozen embryo transfer to see if it improves pregnancy outcomes.
Quick facts
| Study type | Observational |
|---|---|
| Enrollment | 900 (estimated) |
| Ages | 18 Years to 45 Years |
| Sex | Female |
| Sponsor | Mỹ Đức Hospital Academic / other |
| Locations | 2 sites (Ho Chi Minh City, Ho Chi Minh and 1 other locations) |
| Trial ID | NCT07257250 on ClinicalTrials.gov |
What this trial studies
The analysis emulates a randomized target trial using routinely collected records from My Duc Hospital and My Duc Phu Nhuan Hospital in Ho Chi Minh City between 2019 and 2024. Eligible women are 18–45 years old with subclinical hypothyroidism (TSH 4.2–<10 mIU/L and normal FT4) who underwent IVF/ICSI followed by frozen embryo transfer. The exposed group received levothyroxine 25–50 µg/day started before planned FET and titrated every 2–4 weeks to reach TSH <2.5 mIU/L, while the unexposed group was managed expectantly; timing and lab targets are used to emulate random assignment. Outcomes of interest include implantation, miscarriage, preterm birth, hypertensive disorders, and live birth, with statistical methods to account for confounding by indication.
Who should consider this trial
Good fit: Women aged 18–45 with subclinical hypothyroidism (TSH 4.2–<10 mIU/L and FT4 within the normal range) who are undergoing IVF or ICSI followed by frozen embryo transfer and receiving care at the participating My Duc centers.
Not a fit: Patients with overt hypothyroidism (TSH ≥10 mIU/L or low FT4), those already on levothyroxine or other thyroid‑active drugs within the prior month, or those whose infertility is unrelated to thyroid status may not derive additional benefit from this approach.
Why it matters
Potential benefit: If successful, this approach could reduce miscarriage and improve live birth rates for women with subclinical hypothyroidism undergoing IVF/ICSI with frozen embryo transfer.
How similar studies have performed: Previous randomized trials and meta‑analyses have reported mixed results—some showing reductions in miscarriage or neonatal mortality with levothyroxine in mild thyroid dysfunction, but overall evidence remains inconclusive for improving IVF outcomes.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Women aged 18-45 years. * Diagnosed with subclinical hypothyroidism (TSH 4.2-\<10 mIU/L with FT4 0.92-1.68 ng/dL). * Undergoing in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) followed by frozen embryo transfer (FET). Exclusion Criteria: * Overt hypothyroidism (TSH ≥10 mIU/L and FT4 ≤0.92 ng/dL). * Current or recent (within 1 month) use of drugs affecting thyroid function (levothyroxine, amiodarone, methimazole, propylthiouracil).
Where this trial is running
Ho Chi Minh City, Ho Chi Minh and 1 other locations
- My Duc Hospital — Ho Chi Minh City, Ho Chi Minh, Vietnam (Recruiting)
- My Duc Hospital — Ho Chi Minh City, Ho Chi Minh, Vietnam (Completed)
Study contacts
- Study coordinator: Hoanh Kieu Tran, Doctor
- Email: trankieuhoanh@myduchospital.vn
- Phone: +84 982 741 425
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.