If you or a close relative have ever had an over- or underactive thyroid you should tell your obstetrician so you can be sure your thyroid function is checked before, during, and after pregnancy. Abnormal thyroid levels before pregnancy can make it more difficult to conceive. Your baby relies in part on your supplying thyroid hormone, especially before your baby's thyroid begins to develop at about the tenth week of pregnancy.
If you have ever had the form of hyperthyroidism known as Graves' disease, your obstetrician should test your blood for thyroid stimulating immunoglobulins (TSI's), thyroid antibodies which caused your thyroid to become overactive and could have the same effect on your baby during pregnancy if your antibody levels are still increased. This could be your situation even though you feel completely well, even if you are taking thyroid hormone tablets once a day to treat an underactive thyroid.
There is another reason for re-testing your thyroid by means of a TSH test as pregnancy progresses. During pregnancy a mother's thyroid function gradually increases. If your thyroid is underactive, it cannot make more hormone during pregnancy. Therefore, your obstetrician will use TSH tests to tell whether your thyroid hormone dose needs to be increased as pregnancy progresses.
The birth of a baby is a joyous occasion. However, in the postpartum period you will experience many changes in your life. These may include physical problems of fatigue, anemia, pain (from an episiotomy or cesarean section) and breast soreness. Fatigue is especially common because of late night feedings and the continuous responsibilities of a new baby. The "blues" of postpartum depression are common.
These complications usually occur soon after the baby is born, and by the third month after delivery most women are feeling well again. Unfortunately, that is not always the case, and some women do not enjoy a rapid return to good health. For many of these mothers, the cause may be a change in thyroid function after delivery.
During pregnancy your immune system is suppressed as a protection for your baby. After delivery there is a marked rise in immune activity and sometimes a worsening of immune conditions such as rheumatoid arthritis and thyroid disease. Although thyroid dysfunction may occur anytime after pregnancy, it is most common about two to three months after delivery. By that time, your visits to your obstetrician may have ended if you had an uneventful pregnancy and delivery. Therefore you may be more likely to visit your family physician or even the baby's pediatrician. Don't hesitate to discuss your thyroid condition with these caregivers.
If your thyroid levels rise (hyperthyroidism) your whole system may feel speeded up. Your heart may race and you may feel nervous with shaking hands, increased sweating, insomnia, and anxiety. If your thyroid levels fall you could feel sluggish, tired, run down, depressed, and experience muscle cramps and constipation. In either instance your thyroid gland in the front of your neck may enlarge slightly and may feel mildly tender though extreme pain is uncommon.
Anyone with the symptoms of an overactive or underactive thyroid or postpartum depression should have a TSH test to tell whether thyroid levels are normal. Thyroid hormone levels do not need to be checked unless the TSH is high (indicating hypothyroidism) or low (indicating hyperthyroidism).
Since the symptoms of a change in thyroid function may be so mild as to be missed or mistaken for other health problems, your doctor may also choose to check your TSH level about two to four months after delivery if you or a close relative have ever had a thyroid problem. You may also have a TSH test after pregnancy if your doctor suspects that you are at increased risk for thyroid dysfunction. This could be your situation if you or close relatives have other disorders or physical traits suggesting an increased risk for thyroid problems. These include juvenile (Type I) diabetes, rheumatoid arthritis, pernicious anemia due to a lack of vitamin B12, colitis, and prematurely gray hair. There is even new research which suggests that if you or a close relative are either left-handed or ambidextrous you may have an increased risk for thyroid dysfunction and other immune problems.
If your close relatives have these thyroid or related conditions, your doctor may order a TSH test to be sure your thyroid is normal even if you feel well. This is because mild changes in thyroid function often don't appear to cause symptoms, but once treated you may find yourself healthier as symptoms you thought were due to other problems disappear. If you are found to have a thyroid problem, it's likely that you will recover and be able to stop treatment in a few months. However, not all patients get completely well. About one-third of the women who experience changes in thyroid function after pregnancy never fully recover and need thyroid treatment lifelong.
If you have experienced a change in thyroid function in one pregnancy it is likely that your thyroid levels will change after subsequent pregnancies as well. In fact, your obstetrician is likely to order a TSH test to check your thyroid before and during your pregnancy, and after delivery too.
Here the news is good. Most babies have completely normal thyroid function even if a mother has a thyroid problem during the pregnancy or after delivery.
There is more good news. Every baby in the United States, Canada, and most developed countries is checked at birth to be sure thyroid function is normal. This is because babies with a thyroid problem may look normal for two to three months and a delay in treatment of a baby born without a thyroid or with a poorly-functioning thyroid gland may have long-term effects on the baby's health and mental function. Be happy that your baby gets a check automatically. Above all, don't hesitate to talk with your obstetrician about your thyroid, especially if you or one of your relatives has a thyroid or related immune disorder.
The Thyroid Foundation of America relies on individuals like you to help us raise the funds we need to help others with thyroid problems.