What is a common obstetric risk associated with untreated hypothyroidism?

Untreated hypothyroidism during pregnancy is associated with several risks, and one of the most significant is preterm birth. Hypothyroidism can lead to metabolic and hormonal imbalances that affect the pregnancy. It can result in complications such as poor fetal growth, which may contribute to the decision for early delivery to prevent further risks to both the mother and the fetus. Additionally, untreated hypothyroidism can lead to higher rates of maternal and fetal complications, increasing the likelihood of preterm labor or the need for a preterm delivery.

While the other options present potential concerns during pregnancy, they are not as directly linked to untreated hypothyroidism as preterm birth. For example, gestational diabetes is primarily related to glucose metabolism and may not have a direct association with thyroid function. Similarly, placenta previa involves the placement of the placenta and is not a consequence of thyroid status, and hyperemesis gravidarum is characterized by severe nausea and vomiting in pregnancy, typically related to hormonal changes rather than thyroid hormone levels. Thus, preterm birth stands out as the most relevant obstetric risk associated with untreated hypothyroidism.