Studies Evaluate Thyroid Treatment During Pregnancy

ByABC News
September 25, 2009, 5:23 PM

Sept. 26 -- FRIDAY, Sept. 25 (HealthDay News) -- Thyroid problems in pregnant women can cause serious consequences in both mothers and children, says an expert familiar with ongoing research into treatments.

An update on clinical trials was to be presented Friday at the annual meeting of the American Thyroid Association, in Palm Beach, Fla.

"Detection and management of thyroid dysfunction during pregnancy is important for many reasons," Dr. Alex Stagnaro-Green, senior associate dean at the Touro University College of Medicine in New Jersey, said in a news release from the association. "For pregnant women with hypothyroidism, there is an increased risk for miscarriage, an increased preterm delivery, an increased risk for decreased IQ and visual motor defects for their offspring."

Stagnaro-Green said that researchers at the U.S. National Institute of Child Health and Human Development are conducting a randomized trial of thyroid drug therapy for pregnant women with hypothyroidism (insufficient production of thyroid hormone) or hypothyroxinemia (abnormally low concentrations of the hormone thyroxine in the blood).

The main goal of the study is to determine if thyroxine treatment in pregnant women is associated with improved intellectual function in their children at age 5. The researchers also want to find out whether thyroxine treatment affects fetal growth, preterm birth or preeclampsia.

"Newborn follow-ups are scheduled at 12, 24 and 36 months and at ages 4 and 5 years," Stagnaro-Green said.

A similar trial being carried out in Britain and Italy -- the Controlled Antenatal Thyroid Screening Study -- is investigating the effect of thyroid treatment on children's intellectual function at age 3.

About one in eight women will develop a thyroid disorder at some point in her life, according to the American Thyroid Association. Women are five to eight times more likely than men to have thyroid problems. Pregnant women with undiagnosed or inadequately treated hypothyroidism are at increased risk for miscarriage and preterm delivery, and their children face a greater risk for severe developmental problems.