Under and overtreatment with thyroid hormone replacement during pregnancy

Area of Science:

• Endocrinology
• Reproductive Medicine
• Maternal-Fetal Medicine

Background:

• Thyroid hormone replacement therapy is common in pregnant women.
• Both undertreatment and overtreatment of maternal thyroid hormone can lead to adverse maternofetal and offspring outcomes.
• Existing research on the effects of thyroid hormone imbalance during pregnancy shows inconsistent results.

Purpose of the Study:

• To review recent evidence on the effects of maternal thyroid hormone undertreatment and overtreatment during pregnancy.
• To discuss potential improvements in current clinical practices for thyroid hormone replacement therapy in pregnant individuals.

Main Methods:

• Literature review of recent studies on thyroid hormone replacement therapy in pregnancy.
• Analysis of data concerning maternofetal and offspring outcomes related to thyroid hormone levels.
• Evaluation of current adherence and counseling practices for levothyroxine use during pregnancy.

Main Results:

• Undertreatment of hypothyroidism in pregnant women is more prevalent than overtreatment.
• Associations between adverse maternal, neonatal, and offspring outcomes exist for both overt and subclinical hypothyroidism.
• Subclinical hyperthyroidism in pregnancy is associated with fewer adverse outcomes.
• Levothyroxine adherence and provider counseling during pregnancy are suboptimal.

Conclusions:

• Undertreatment of maternal hypothyroidism poses a greater risk for adverse maternofetal and offspring effects compared to overtreatment.
• Frequent thyroid function monitoring is essential during pregnancy to prevent under- or overtreatment when thyroid hormone replacement therapy is indicated.
• Effective clinician-patient communication is imperative to enhance medication adherence and optimize therapeutic outcomes.