The thyroid is hyper stimulated during pregnancy, resulting in alterations in thyroid hormone concentrations. Thyroid function must be accurately assessed throughout pregnancy for both the commencement of thyroid hormone therapy and the adjustment of thyroid hormone dose in those who are currently taking thyroid hormone. Thyroid insufficiency is linked to poor obstetric outcomes and foetal neurodevelopmental impairments, hence trimester-specific intervals are especially crucial during pregnancy. Thyroid function assays now provide gestational age-specific reference intervals. Knowing what to expect in terms of natural changes in hormone concentrations throughout pregnancy allows for tailored supplementation if needed.
The thyroid gland and its function are significantly affected by pregnancy. In pregnancy, hypothyroidism is described as a rise in TSH levels in the blood. It’s also divided into overt (lower free T4 levels) and subclinical hypothyroidism (normal free T4 levels) based on free T4 levels.
Hypothyroidism affects 1.5 percent to 4% of pregnant women worldwide, according to many studies. Overt hypothyroidism (OH) affected 0.3 to 0.5 percent of them, while the rest had subclinical hypothyroidism (SCH). Various studies in India found that the frequency of maternal hypothyroidism ranged from 1.2 percent to 67.0 percent.
Hypothyroidism is estimated to affect 2% to 3% of pregnant women. OH accounts for 0.3-0.5 percent of them, while SCH accounts for 2-2.5 percent. Untreated OH has been linked to a 60% chance of foetal loss and a 22% chance of gestational hypertension in studies. There has been a strong link established between OH and increased danger to the maternal-fetal unit. SCH women have a 6 percent miscarriage rate compared to 3.6 percent for euthyroid women. Untreated women with SCH have a two-to-threefold greater risk of pregnancy-related problems.
Those over the age of 30, those with a personal or family history of thyroid disease, women having difficulty conceiving, and those with autoimmune diseases should all be screened for thyroid abnormalities during pregnancy, according to the Endocrine Society. Thyroid hormones are critical for foetal brain development and other aspects of foetal growth, thus it’s critical that antenatal care providers recognize thyroid problems and refer patients to expert specialists when clinically appropriate. New data is surfacing in an attempt to shed light on areas of contention and doubt. This review summarizes recent advances in our understanding of the effects of thyroid abnormalities during pregnancy and assisted conception, as well as how to treat them.
