Thyroid disorders typically cause an abnormal increase or decrease in the amount of hormone produced by the thyroid gland. An increase in hormones is called hyperthyroidism. A decrease is called hypothyroidism.
Women are far more likely than men to develop certain thyroid disorders. The University of Maryland Medical Center notes that Hashimoto’s thyroiditis, the form of hypothyroidism most frequently reported in the United States, is up to 20 times more common in women than in men. Grave's disease, the most common hyperthyroid condition, occurs seven times more frequently in women than it does in men.
Menstrual Changes
Thyroid hormones are responsible for regulating metabolism, the rate at which the body burns energy. Increased levels of thyroid hormone boost metabolism. Hyperthyroid patients often report that their menstrual periods decrease in frequency and that bleeding is lighter.
Women who have hypothyroid disorders experience a slowing down of metabolism, with symptoms developing slowly. Over several years menstrual flow may increase, and excessive menstrual bleeding is a common symptom in women with hypothyroidism, according to the National Women’s Health Information Center.
Brittle Bones
Postmenopausal women with hyperthyroidism are at especially high risk for osteoporosis. Brittle bones can be one of the first signs of hyperthyroid disease. Dr. Daniel Drucker of the endocrinology division at the University of Toronto states that patients with abnormally high thyroid hormone levels have a significantly increased risk of fractures.
Infertility
Thyroid disorders can impair a woman’s ability to get pregnant. Mayo Clinic.com explains that thyroid levels influence fertility, and low levels of thyroid hormone decrease the likelihood of ovulation.
Pregnancy Complications
Abnormal levels of thyroid hormone can cause problems during pregnancy. Increased hormones have been associated with complications in unborn children such as accelerated heart rates, lower birth weights, premature births and stillbirths. Mothers with hyperthyroidism may suffer from preeclampsia.
Decreased thyroid hormone levels in pregnancy can also result in preeclampsia, as well as anemia and abnormal bleeding after birth. Brain development problems may occur in babies of mothers with hypothyroidism.
Postpartum Complications
Between 5 percent and 10 percent of women in the U.S. experience changes in their metabolism following pregnancy because of thyroid inflammation, according to the National Women’s Health Information Center. The symptoms of this inflammation, called postpartum thyroiditis, begin one to four months after giving birth. During this phase the patient may experience increased heart rate, irritability and weight loss because of hyperthyroidism, according to the American Thyroid Association.
As the thyroid gland becomes exhausted by overuse, thyroid hormone production can decrease, causing levels to dip to hypothyroid levels. During this phase of postpartum thyroiditis, which occurs four to eight months after delivery, fatigue, weight gain and constipation may occur.
