Struggling to get pregnant? When was the last time you had your thyroid gland checked?
“More and more infertility clinics are screening women who are having difficulty getting pregnant for thyroid dysfunction,” notes Dr. Bradley Van Voorhis, president of the Society for Reproductive Endocrinology & Infertility (SREI).
The thyroid gland, located in the neck, produces hormones that help regulate metabolism and energy. Too much or too little of these hormones can affect ovarian function.
If you’re experiencing irregular periods or you are concerned you’re not ovulating, you should ask your doctor to check your thyroid-stimulating hormone, or TSH, levels. That will indicate if your thyroid is functioning correctly. Women with a history of thyroid problems—their own or in their family—most likely have already been screened for thyroid function.
If your blood work does indicate the presence of a thyroid disorder, that doesn’t mean you can’t get pregnant, though it may take longer. “Many women still get pregnant with thyroid disorder,” Van Voorhis says. Some doctors will advise that you hold off on trying to conceive until your hormone levels are healthy, but that may only take a few months.
Once pregnant, it’s important to be vigilant in controlling your thyroid function. There is evidence that women who have hypothyroidism, or an underactive thyroid, have a slightly increased risk of miscarriage. There’s also an association with preterm delivery and hypothyroidism, which is the most common type of thyroid disorder.
A study recently published in the Journal of Clinical Endocrinology & Metabolism found that 15 percent of 500,000 pregnant women tested in a study had an underactive thyroid—a number significantly higher than some previous estimates. In the past, it was also believed that low thyroid levels in pregnant women could affect their children’s intelligence. But a recent study in the New England Journal of Medicine suggests that treating the mother with synthetic hormone during pregnancy doesn’t seem to increase cognitive function in her child by age three.
It’s safe for women to take the synthetic thyroid hormone treatment for hypothyroidism during pregnancy, but they typically have to increase their dosage. A woman’s obstetrician will monitor her TSH each trimester to make sure the supplement is adequate. After delivery, the doctor will probably decrease the amount of thyroid hormone again.