LIGHT Trial: Levothyroxine for Gestational Hypothyroidism in Recurrent Pregnancy Loss

Women's Hospital School Of Medicine Zhejiang University

Status and phase: Not yet enrolling; Phase 3

Conditions: Abortion, Habitual

Treatments: Drug: Levothyroxin; Drug: Placebo

Study type: Interventional

Funder types: Other

Identifiers

NCT06999278

IRB-20250069-R

Details and patient eligibility

About

The goal of this randomized, double-blind, placebo-controlled clinical trial is to evaluate whether levothyroxine supplement improves pregnancy outcomes in women with recurrent pregnancy loss (RPL) and isolated maternal hypothyroidism (IMH).

The main questions it aims to answer are:

Does levothyroxine increase the live birth rate after 24 weeks of gestation? Does levothyroxine improve secondary outcomes such as ongoing pregnancy rates, reduce the incidence of pregnancy loss, or influence maternal and neonatal complications?

Researchers will:

Compare the levothyroxine treatment group (50 µg/day) to the placebo group to assess the impact of the intervention on live birth rates and other pregnancy outcomes.

Participants will:

Be randomly assigned to receive either levothyroxine or a placebo. Take the assigned treatment daily starting from enrollment until the end of pregnancy.

Undergo routine follow-up visits to monitor pregnancy progress and outcomes. This trial seeks to determine whether routine levothyroxine supplementation can improve pregnancy outcomes for women with RPL and IMH.

Full description

Investigators will perform a multi-center, randomized, placebo, double-blind clinical trial of levothyroxine (LT4) in patients aged between 18 years and 40 yearls who are diagnosed with isolated hypothyroxemia (defined as lower FT4 level with normal TSH) and have a previous history of recurrent miscarriages (defined as two or more pregnancy loss). Investigators will assess the effects of standard dose of 50ug/d levothyroxine therapy from the day after randomization to the day of delivery on the pregnancy outcomes, including live birth, neonatal complications, and adverse pregnancy outcomes, etc.

Enrollment: 200 estimated patients

Sex: Female

Ages: 18 to 40 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• women with singleton pregnancy
• women with a history of recurrent pregnancy loss (defined as two or more pregnancy loss before 20wks)
• women diagnosed with isolated maternal hypothyroidism (defined as isolated lower level of FT4 with normal TSH levels) in the current pregnancy before 20wks

Exclusion criteria

• patients with known thyroid disorders
• patients with antiphospholipid syndrome or other autoimmune conditions
• patients with contraindications to levothyroxine (e.g., acute cardiac arrest, acute pancreatitis, acute myocarditis)
• patients attending other ongoing clinical trials or unwilling to participate.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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200 participants in 2 patient groups, including a placebo group

Arm LT4

Experimental group

Description:

The intervention will consist of standard treatment with levothyroxine tablets (50ug/day). The treatment will start from the next day after randomization and end at the day of delivery.

Treatment:

Drug: Levothyroxin

Arm Placebo

Placebo Comparator group

Description:

The intervention will consist of standard treatment with levothyroxine placebo daily. The treatment will start from the next day after randomization and end at the day of delivery.

Treatment:

Drug: Placebo