Thyroid is a butterfly shaped endocrine gland located in the neck which is responsible for secreting thyroid hormone in the blood.
The normal function of thyroid gland (production of T3 and T4 hormones in correct amount by thyroid) is maintained by hypothalamus and pituitary glands located in the brain. The role of hypothalamus is to secrete Thyrotrophin Releasing Hormone (TRH) which signals the pituitary gland to secrete Thyroid Stimulating Hormone (TSH).
When T3 and T4 levels are low in the blood, the pituitary gland releases more TSH to signal the thyroid gland to produce more thyroid hormones (T3 and T4). If T3 and T4 levels are high, the pituitary gland releases lesser TSH, this signals thyroid gland to reduce the production of T3 and T4 hormones.
When thyroid gland produces inadequate hormones, that condition is called Hypothyroidism (an underactive thyroid). When the thyroid gland produces too much hormones, then that condition is called Hyperthyroidism (an overactive thyroid).
Thyroid hormones have significant role in reproduction and pregnancy. According to studies, thyroid dysfunction affects 10 times more to women than men. This dysfunction normally occurs during women reproductive age.
Thyroid dysfunction can affect fertility in various ways resulting in:-
- Anovulatory cycles (not releasing an egg from ovary)
- Luteal Phase Problems (included Difficulty getting pregnant, repeat early miscarriage, short menstrual cycles, and premenstrual spotting etc)
- High prolactin Level
- Other sex hormonal imbalance
- Increased chances of miscarriage
- Poor foetal growth.
- Premature birth and stillbirth
A women with a history of recurrent abortion/ irregular menstrual cycle/ family history of thyroid problem / unable to conceive from last 6 months should contact infertility expert. After the physical examination & going through medical history of patient, infertility expert recommends thyroid screening. This can be done by T3, T4, TSH, and thyroid autoimmune test in the blood. Once the underlying thyroid dysfunction is detected, infertility expert prescribes medications to correct the thyroid hormones level in the blood. This restores the fertility.