Pills are accused of many things, but can birth control measures cause thyroid problems? Endocrinologist Alexandra Mikhael, MD, said: “Whenever someone has a thyroid problem and takes birth control pills, their healthcare provider should monitor their thyroid levels.” Dr. Mikhael explained the connection between birth control pills and the thyroid.
What is the thyroid gland? The thyroid is a butterfly-shaped gland at the bottom of the neck. His compelling job description includes secreted hormones that control metabolism-T4 (thyroxine) and T3 (triiodothyronine). Metabolism refers to the energy produced and used by the body.
The pituitary gland is the thyroid’s partner in crime-it secretes a hormone called TSH (thyroid-stimulating hormone), which tells the thyroid to start making thyroid hormones. T4 is the main hormone secreted by the thyroid gland. The thyroid hormone circulating in our body binds to plasma proteins in the blood and is called:
• Thyroxine binding globulin (TBG).
• Thyroxine (TTR).
Thyroid hormones require blood proteins to spread through your body. So far, TBG has been a major participant in this process. Dr. Mikhael said that there is a good balance between free and bound thyroid hormone levels in our blood. It is the effect of “free” or “unbound” T4 and T3 on our body’s production of thyroid hormones.
Does birth control affect the thyroid? The short answer is: yes. Depending on the type of birth control, the way you start using birth control pills is different. How does birth control affect the thyroid? Contraceptives (oral contraceptives) containing estrogen or estrogen and progesterone can change the delicate balance of free and bound thyroid hormones in the body.
The estrogen in birth control pills increases the amount of thyroid-binding protein that can bind to thyroid hormone. What does this mean to you? If you have more thyroid hormones bound to protein, there will be less free T4 in the body that can do its job.
Therefore, if you are on birth control and need drugs to treat hypothyroidism, you may need higher doses of thyroid drugs to achieve normal thyroid levels. However, if you stop taking estrogen-containing drugs, you may need to use lower doses of thyroid drugs. Dr. Mikhael said that if you have underlying thyroid disease, starting birth control will affect your thyroid. She added that about two weeks after starting oral contraceptives, TBG began to increase.
Thyroid hormone levels reach a stable state within four to eight weeks. In women with hypothyroidism and pregnant women receiving thyroid hormone therapy, the dose of thyroid hormone needs to be increased to maintain normal TSH levels. “Anyone who starts taking birth control pills, whether it is levothyroxine (synthetic T4) or iodothyronine sodium (synthetic T3), should be monitored six to eight weeks after the oral contraceptive starts.”
Dr. Mikhael said that other forms of hormonal birth control (such as skin plaques) do not have the same problems-studies have not shown any link with the increase in thyroid binding protein. “Mainly oral estrogen, with or without progesterone will cause these effects.” Will birth control pills affect thyroid test results? Even if you do not have thyroid disease, birth control measures can affect thyroid test results. E.g:
Medroxyprogesterone Acetate Depot (DMPA): DMPA is a contraceptive method where you only need to take progesterone. Studies have shown that DMPA increases free T4 levels higher than copper intrauterine devices (intrauterine devices). Dr. Mikhael said: “But we don’t know whether this has clinically significant effects.” • Oral micronized progesterone: Studies have shown that this drug can reduce thyroid-stimulating hormone and increase free T4 content. However, it has no effect on the free T3 level.
Dr. Mikhael pointed out: “Many studies have shown that oral contraceptives have a greater impact on thyroid testing than other forms of birth control, but they are usually milder.” “But there is no evidence that contraceptive methods can trigger if you have no underlying thyroid problems. Or cause thyroid problems.” Does thyroid health affect the effectiveness of contraception? Dr. Mikhael said that some data suggest that abnormal thyroid function may affect the effectiveness of birth control-whether you are doing regular adjustments or preventing pregnancy.
“This is why you should talk to your provider before starting the medication. If you have any reason to suspect thyroid disease, please resolve and treat it.”