Many women with postpartum thyroiditis experience hypothyroidism

A study conducted in southern Italy has found that most women who experience postpartum thyroiditis (PPT) go through a period of hypothyroidism.

The research, which appears in the Journal of Clinical Endocrinology and Metabolism, suggests that up to 82 percent of women with PPT will experience low levels of thyroid hormones for at least a few weeks after childbirth.

Overall, the study's authors found that 4 percent of women suffered from PPT in the first year after childbirth, although the team noted that the area from which participants were recruited is noted for mild but widespread iodine deficiency.

The American Thyroid Association (ATA) estimates that between 5 and 10 percent of U.S. women will experience PPT at least once. While the causes of the condition are unknown, the symptoms are relatively easy to detect.

In the hyperthyroid stage, which typically comes first, new mothers may notice a rapid heartbeat, unexplained weight loss, anxiety, exhaustion and sensitivity to heat, according to the Mayo Clinic.

Experts say that in the hypothyroid stage, women may experience weight gain, hoarseness, a puffy face, fatigue, constipation and sensitivity to cold.

This stage is more common and usually develops between four and eight months after delivery, typically lasting up to a year, according to the ATA.

In the Italian study, 54 percent of women had chronic hypothyroidism during the 12 months following childbirth. Researchers did not determine how many of these cases remained beyond the first year.

Among American patients, the ATA estimates that 20 percent of cases of hypothyroidism caused by PPT become permanent, often necessitating thyroid hormone replacement therapy.

The organization notes that beyond pregnancy, those who have a family history of the disorder, dramatic changes in health, thyroid cancer, irradiation of the head and neck or thyroid surgery have an increased risk of hypothyroidism.