Introduction
Thyroid hormones regulate nearly every system in the body. They promote growth and development, influence metabolism, and are necessary for the efficient functioning of the central nervous system, cardiovascular system, immunological system, and reproductive system. Thyroid hormones control the release of the primary reproductive hormones estradiol (E2) and progesterone (P4). These hormones are required for the maturation and development of the oocytes, as well as the preparation of the endometrium for embryo implantation and the establishment and maintenance of early pregnancy. Both E2 and P4 levels have been demonstrated to be reduced in hypothyroidism.
Thyroid diseases are linked to reproductive dysfunction, which includes aberrant sexual development, infertility, or anomalies in the reproductive cycle. It is well documented that endometrial muscle layer thickness and its absolute volume are both decreased in rats with induced hypothyroidism. In people, hypothyroidism can interfere with ovulation and the menstrual cycle. Miscarriage, late-pregnancy difficulties, and issues with implantation and fertilization can also result from it.
What Causes Thyroid Dysfunction?
Disorders like hypothyroidism and hyperthyroidism result from the thyroid gland producing these hormones either insufficiently or excessively. Both men and women can experience thyroid issues. However, women are ten times more likely than males to experience thyroid abnormalities. The interaction between thyroid hormones and female reproductive hormones like estrogen and progesterone are responsible for this effect.
The overproduction or underproduction of thyroid hormones is the most common cause of thyroid dysfunction. In addition to these, it may also be brought on by Graves' disease and Hashimoto's disease, two autoimmune conditions that trigger the body's immune system to target the thyroid gland. In the instance of Hashimoto's illness, the affected thyroid gland initially produces too many hormones before ceasing entirely, leading to hypothyroidism.
As opposed to Graves' disease, which results in hyperthyroidism when the thyroid gland releases excessive amounts of thyroid hormones. Pituitary gland issues can occasionally bring on hypothyroidism. Thyroid-stimulating hormone is produced by this gland and instructs the thyroid to function. Temporary thyroid inflammation or drugs that interfere with thyroid function are some other reasons for hypothyroidism.
What Effects Do Thyroid Issues Have on Women?
Thyroid disorders are more prevalent in women than in men. Thyroid issues affect one in every eight women throughout their lifetime. Thyroid problems in women can result in the following way:
1. Menstrual Cycle Issue
The thyroid aids in regulating the menstrual cycle if women have issues with it. Periods may become extremely light, heavy, or erratic due to excess or insufficient thyroid hormone. Amenorrhea, a disorder brought on by thyroid dysfunction, is the cessation of periods for several months or more. Ovaries and other glands could be affected if the body's immune system is the source of thyroid illness. Due to this, early menopause may result (before age 40).
2. Obstacles to Getting Pregnant
Thyroid condition impacts ovulation when it affects the menstrual cycle. This may make it more difficult for a woman to become pregnant.
3. Pregnancy-Related Issues
Health issues for both the mother and the fetus might result from thyroid issues during pregnancy.
How Does Hypothyroidism Affect Endometrial Thickness?
Prostaglandin endoperoxide synthase 2 aids in ovulation, fertilization, implantation, and decidualization are all crucial reproductive processes. Females that lack prostaglandin-endoperoxide synthase 2 are infertile and have aberrant ovulation, fertilization, implantation, and decidualization processes. The main enzyme in prostaglandin production is called prostaglandin endoperoxide synthase 2. In response to acidogenic stimuli, the rat endometrium gradually expresses the prostaglandin-endoperoxide synthase 2 protein.
According to a study, rats with induced hypothyroidism had considerably lower levels of the protein prostaglandin-endoperoxide synthase 2 than rats in the control group. It is speculated that the lower concentration of prostaglandin-endoperoxide synthase 2 in the group's uterus resulted from the fact that induced hypothyroidism in rats reduced the endometrium's absolute thickness.
Prostaglandins play an undeniably crucial role in embryo implantation. Reduced prostaglandin synthesis in the human endometrium has been associated with poor endometrial receptivity during embryo implantation. On the other hand, it is also known that hypothyroidism can lead to issues with implantation and fertilization, miscarriages, and late-pregnancy complications.
What Are the Reproductive Hormones That Are Influenced by Hypothyroidism?
Estradiol (E2) and progesterone (P4), two female reproductive hormones, are highly influenced by thyroid hormone levels. Progesterone and estradiol play critical roles in establishing and maintaining early pregnancy, the maturation and development of oocytes, and the preparation of the endometrium for embryo implantation. Changes in the physiological levels of these hormones brought on by thyroid hormones may contribute to or disrupt reproductive system disorders.
How Do Thyroid Disorders Affect Ovaries?
Ovarian morphology changes to a polycystic state in hypothyroidism. As a result, one of the exclusion criteria when diagnosing polycystic ovarian disorder in any woman is thyroid issues. Increased thyroid stimulating hormone (TSH) and prolactin are caused by an increase in thyrotropin-releasing hormone (TRH) in primary hypothyroidism (TSH). Prolactin inhibits ovulation due to the altered ratio of follicle-stimulating hormone (FSH) and luteinizing hormone and increased dehydroepiandrosterone from the adrenal gland, which contributes to polycystic ovarian morphology.
Due to its negative impact on follicle-stimulating hormone receptors, the elevated thyroid-stimulating hormone also contributes to infertility. It has also been proposed that hypothyroidism causes increased collagen deposition in the ovaries. The length and severity of the underlying primary hypothyroidism also affect the severity of ovarian morphology. Ovarian morphology can be extremely noticeable and even mistaken for ovarian cancer in the most severe circumstances, such as protracted untreated congenital hypothyroidism.
Conclusion
In hypothyroidism, the thyroid gland produces insufficient amounts of crucial hormones. Low thyroid hormone levels can interfere with ovulation (the release of an egg from the ovary), which reduces fertility. Additionally, certain autoimmune or pituitary problems, one of the underlying causes of hypothyroidism, may affect fertility. Inform the doctor right away if women become pregnant and women have hypothyroidism.
Thyroid hormone levels should be closely monitored throughout pregnancy to support healthy fetal development and lower the chance of miscarriage. Depending on the patient's condition, the course of treatment will vary. Typically, thyroid hormone levels are restored with the aid of tablets to treat hypothyroidism and its symptoms. The majority of people will require these medications for the remainder of their lives. To know more about this condition, patients can also consult online.
