Can high thyroid-stimulating hormone (TSH) levels cause fetal arrest?

Elevated levels of thyroid-stimulating hormone (TSH) typically indicate hypothyroidism, a condition clinically referred to as "underactive thyroid." Thyroid hormones are crucial for the development of both the mother and the fetus during pregnancy, as they influence metabolism, growth, and brain development.

If a pregnant woman's TSH levels are excessively high and remain untreated, it may increase the risk of certain pregnancy complications, including preterm birth, low birth weight infants, and fetal neural tube defects. Regarding embryonic or fetal demise, although there is no direct evidence that elevated TSH levels alone are the sole cause of fetal arrest, they may affect normal embryonic development in early pregnancy and increase the risk of adverse pregnancy outcomes.

Therefore, women who are planning to become pregnant or are already pregnant should regularly monitor their thyroid function. If elevated TSH levels are detected, doctors typically recommend initiating thyroid hormone replacement therapy to maintain normal hormone levels.