When a woman thinks of getting pregnant, thoughts of having her thyroid hormone levels checked doesn’t even come to mind. Her thyroid doctor may not even suggest it. In fact, many infertility doctors are unaware of how thyroid function can impact a woman’s ability to conceive. Thyroid hormones directly affect the uterine lining, causing infertility or miscarriages to occur. Unfortunately, obstetricians and gynecologists are the doctors women look to when dealing with fertility issues or pregnancy. Arming more women with accurate information regarding the importance of thyroid function may prove helpful in educating more doctors working in other fields of medicine
According to the Thyroid Federation International over 300 million individuals have a thyroid hormone imbalance, occurring predominantly in women, who are completely unaware they have an imbalance. This is unfortunate as thyroid hormone levels during pregnancy can have very devastating effects on the health of an unborn baby. When thyroid hormone levels are either too high or low, the baby’s psychomotor skills, cognitive function, and brain development can be severely affected.
Thyroid hormone imbalance also affects the mother during her pregnancy. Hair loss, morning sickness, fatigue, or the chance of experiencing depression may be increased when thyroid function is compromised.
How Does Thyroid Dysfunction Cause Infertility?
Women with low thyroid hormone levels (hypothyroidism) are much more likely to have problems getting pregnant or maintaining a pregnancy after conception. The TSH (thyroid stimulating hormone) and TRH (thyrotropin-releasing hormone) are kicked into action when thyroid hormone levels fall too low. TRH is produced by the hypothalamus and stimulates the pituitary gland to release TSH. Infertility occurs because TRH is also responsible for stimulating the pituitary to release prolactin. Prolactin is responsible for promoting lactation but also interferes with the ovulation process. The increased prolactin levels prevent the ovaries from releasing an egg each month, sometimes skipping months before the release of another egg. This inconsistency can make it nearly impossible to get pregnant.
Thyroid hormones are also responsible for the health of the your uterine lining. Overproduction of thyroid hormones increase the body’s metabolism of sex hormones such as estrogen, preventing a healthy uterine lining from developing. A weakened uterine lining interferes with the implantation of a fertilized egg and does not support a nurturing environment for a fetus to grow.
How Does Thyroid Dysfunction Affect the Fetus?
Low thyroid hormone levels prior to becoming pregnant, or developed during pregnancy, can have a profound effect on an unborn baby’s brain development. For the first 12 weeks in utero, the baby relies on the thyroid function of its mother to nurture and promote healthy development. Fetal thyroid development or function does not occur until the third month of pregnancy.
Many studies have shown that low thyroid hormone is responsible for the misplacement of neurons in the developing brain of a fetus. When neurons are misplaced in the brain, IQ is significantly lowered, and cognitive function and psychomotor skills are affected as well.
A woman with overactive thyroid hormone levels can increase the baby’s heart rate in utero. Overactive hormones also increase the level of TSH antibodies produced and transferred to the baby through the placenta. Increased levels of TSH antibodies may cause goiter or bone abnormalities to develop in the fetus, and lower birth weight as well. The result of imbalanced hormones can affect the health of your baby!
What to do Before Becoming Pregnant
Women who are aware they have hypothyroid or hyperthyroid issues should be properly treated and have stabilized thyroid hormone levels before deciding to become pregnant. It will also be very important to check your thyroid hormones frequently during your pregnancy to maintain adequate levels needed for you and your baby’s health.
It is very important for all women to talk to their thyroid doctor and get their hormone levels checked frequently, especially before deciding to become pregnant. Awareness of your thyroid function before and during pregnancy will increase your chances of becoming pregnant, prevent miscarriages from occurring, and most importantly provide your baby with the ability to develop an awesome mind and body!