Why are tetracyclines contraindicated in pregnancy?

Why are tetracyclines contraindicated in pregnancy?

• A. They can impair fetal bone growth and cause tooth discoloration
• B. Neural tube defects
• C. They induce heavy sedation
• D. They cause renal failure in mother

Answer: (A)

Tetracyclines cross the placenta and become incorporated into calcifying fetal tissues by binding calcium. In developing teeth and bones, this leads to permanent tooth discoloration and can affect enamel formation, with potential effects on fetal bone growth. Because these changes are lasting and occur during critical periods of tooth and bone development, tetracyclines are avoided during pregnancy. The other options don’t reflect the well-established fetal risks of this drug class in pregnancy—neural tube defects, heavy sedation, or maternal renal failure aren’t the primary concerns associated with tetracycline use.

Tetracyclines cross the placenta and become incorporated into calcifying fetal tissues by binding calcium. In developing teeth and bones, this leads to permanent tooth discoloration and can affect enamel formation, with potential effects on fetal bone growth. Because these changes are lasting and occur during critical periods of tooth and bone development, tetracyclines are avoided during pregnancy. The other options don’t reflect the well-established fetal risks of this drug class in pregnancy—neural tube defects, heavy sedation, or maternal renal failure aren’t the primary concerns associated with tetracycline use.