Introduction
The interactions between the fetoplacental unit and the maternal endocrine system lead to the significant hormonal changes needed during pregnancy. These significant modifications are essential for a healthy pregnancy, birth, and breastfeeding. Pregnancy affects almost all endocrine axes. Hence, it is important to take caution when interpreting the results of biochemical tests designed to measure endocrine function. Additional monitoring may be necessary during the prenatal and postnatal periods since changes during pregnancy might also affect the clinical course of endocrine disorders (such as prolactinomas).
Which Are the Common Endocrine Diseases Which Occur During Pregnancy?
Below are some common diseases:
Pituitary Disease
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Prolactinomas: The most frequent pituitary tumors observed in women of childbearing age are prolactinomas. Due to its ability to prevent the production of pulsatile gonadotropin-releasing hormone from the brain, hyperprolactinemia is a major cause of infertility in women. An increased chance of pregnancy can result after dopamine agonist therapy due to the quick recovery of fertility. Prolactin levels are rarely helpful in diagnosing or treating prolactinoma because they rise in the blood during a healthy pregnancy. The pituitary enlarges during a typical pregnancy, much as a prolactinoma may enlarge.
The risk is highest in the third trimester and is more common for macroprolactinomas (>10 mm in size) than for microprolactinomas (10 mm). If the prolactinoma has been detected and treated before conception, the risk of tumor growth is decreased. Every trimester should include visual field testing, and pituitary imaging is necessary if tumor growth is suspected based on the symptoms described or changes in the visual fields. Dopamine receptor antagonists should not be used during the first trimester of pregnancy.
However, they may be continued in patients with macroprolactinomas who risk their tumors becoming symptomatic. These medications can be restarted and continued by lactating moms if there is verifiable evidence of tumor enlargement without harming the newborn; however, they can obstruct breastfeeding. Because there is a potential risk of fetal or maternal cardiac valve fibrosis, the British Medicine and Healthcare Products Regulatory Authority has recommended that pregnancy be ruled out before ergot derivatives (cabergoline and bromocriptine) are used. However, there are currently no studies that back up this recommendation.
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Acromegaly: Acromegaly patients seldom become pregnant because the majority have curative surgery. Those who do not frequently struggle with infertility due to hyperprolactinemia from pituitary stalk compression. The diagnosis of acromegaly may not be confirmed until after the birth when levels of placental growth hormone rapidly decline because most diagnostic assays cannot differentiate between pituitary and placental growth hormone. Additionally, normal pregnancy has higher quantities of insulin-like growth factor.
Acromegaly can raise the chance of developing gestational diabetes and perinatal hypertension. Pregnancy can bring on the earliest signs of the associated heart disorders, such as cardiomyopathy and coronary artery disease. Pregnancy frequently results in a break in medical care. Due to the lack of conclusive safety data around their usage, dopamine receptor antagonists are often terminated early in pregnancy, and somatostatin analogs are withheld.
The course of the disorder is typically unaffected by an interruption during pregnancy. However, this should be determined on a case-by-case basis. There have been a few reports of tumor growth and one case of pituitary apoplexy. Still, only a small percentage of women with acromegaly have had this disease worsen during pregnancy. Therefore, pregnant women with acromegaly should follow the same guidelines for prolactinomas regarding tumor sizing and surveillance.
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Pituitary Insufficiency: Pituitary insufficiency can be brought on by lesions such as adenomas, infarctions, or lymphocytic hypophysitis, as well as previous pituitary surgery or radiotherapy. As the gonadotrophin stimulation to ovulation may not be present, it may result in subfertility, necessitating ovulation-induction medications. The outcome for either the mother or the fetus is unaffected by this disease if enough hormone replacement has been obtained before conception. It may be linked to miscarriage and stillbirth if the problem is not properly detected or treated.
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Lymphocytic Hypophysitis: In late pregnancy and after delivery, lymphocytic hypophysitis is more common. Adrenocorticotropic hormone (ACTH) deficit can result from lymphocytic hypophysitis, as opposed to pituitary insufficiency from most other causes. Because pregnancy affects the hormone levels used to detect pituitary insufficiency, diagnosis in the acute context is difficult.
Assessment of the thyroid and corticoadrenal axis is all that can be done to diagnose because luteinizing hormone (LH) and follicle-stimulating hormone (FSH) are inhibited. The extended half-life of thyroxine (T4) may initially cause thyroid function to appear normal, making repeated testing crucial. Cortisol and ACTH levels are used to measure the corticoadrenal axis. An ACTH stimulation test cannot be used to diagnose acute pituitary insufficiency since the adrenal response to ACTH will stay normal in this condition.
Thyroid Disease:
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Normal Changes in Pregnancy: Thyroid function test findings during pregnancy differ from those in the general population. Molar pregnancies, multiple pregnancies, or hyperemesis gravidarum are examples of conditions linked with higher levels of human chorionic gonadotropin (HCG), which can lead to biochemical abnormalities that would normally signal thyrotoxicosis.
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Hypothyroidism: Up to 1 percent of pregnant women have hypothyroidism, most of whom were diagnosed and received treatment before conception. Lethargy, weight gain, and constipation are just a few of the typical clinical symptoms of hypothyroidism that are present in a healthy pregnancy. Cold intolerance, bradycardia, and delayed tendon reflex relaxation are more particular characteristics. Therefore, elevated thyroid-stimulating hormone (TSH) and low free thyroxine (fT4) concentrations are used to diagnose. Due to ovulation suppression, untreated hypothyroidism can cause amenorrhea and infertility. Following conception, it is linked to a higher incidence of miscarriage, anemia, pre-eclampsia, and low birth weight babies. A severe maternal iodine shortage can harm the developing fetus and cause newborn hypothyroidism with poor cognitive and physical growth.
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Hyperthyroidism: Approximately 1 in 500 pregnancies are complicated by hyperthyroidism. If a pre-existing condition is not appropriately managed, infertility may result. Miscarriage, premature labor, and fetal development limitations linked to uncontrolled disease are less common if proper therapy is started along with the normalization of thyroid function. Due to certain immunosuppression that occurs during pregnancy, autoimmune thyrotoxicosis may improve, but there is a chance that it will worsen after birth. When hyperthyroidism is newly discovered during pregnancy, anti-thyroid medication must be started immediately. If necessary, beta blockers can also be utilized. Radio-iodine is not advised during pregnancy since it may result in fetal hypothyroidism, and surgery is rarely performed.
Conclusion
Endocrine disorders during pregnancy must be researched and treated with a multidisciplinary approach. It can be difficult to decide on the timing and suitability of surgery during pregnancy or on empirical treatment without a confirmed diagnosis. The evidence used to make judgments is not as substantial as it is for the non-pregnant population due to the lack of numerous comparable cases or trials of specific treatments during pregnancy. Therefore, it's critical to tailor treatment to the unique requirements of each patient and the issue at hand.
