How does the use of tetracycline during pregnancy affect the fetus?

The use of tetracycline during pregnancy is known to have significant implications for fetal development, particularly concerning dental and bone health. Tetracycline can lead to permanent discoloration of the teeth in the developing fetus. This is due to the affinity of tetracycline for calcium ions, which are abundant in developing teeth. When the drug is taken during critical periods of tooth development, it can become incorporated into the tooth structure, resulting in a yellow, gray, or brown discoloration.

Additionally, tetracycline affects bone development because it can also bind to calcium in bones. This can lead to inhibition of bone growth and development, potentially resulting in skeletal abnormalities. Given these serious risks, the use of tetracycline during pregnancy is typically contraindicated, especially in its second and third trimesters.

Other options do not reflect the known effects of tetracycline. While there are various factors associated with pregnancy that can lead to complications, the specific risks of heart defects or premature birth are not directly associated with tetracycline use. The well-documented risk of tooth discoloration and impaired bone development stands out as the primary concern for any pregnant patient considering this medication.