Which statement best describes pubertal gynecomastia?

• A. It is rare during puberty
• B. It is common during puberty and due to estrogen androgen imbalance
• C. It always resolves within days
• D. It is caused by infection

Answer: (B)

Pubertal gynecomastia happens because hormonal changes in adolescence can create a temporary imbalance between estrogen and androgen effects on breast tissue. Estrogen stimulates breast tissue growth, and during puberty there’s a period where this effect can be relatively stronger or not yet fully countered by androgen action. The result is benign enlargement of glandular tissue under the nipple that is typically bilateral and self-limited.

This pattern—common occurrence during puberty, driven by a transient estrogen–androgen balance shift, and usually resolving as hormones stabilize—best describes what happens. It’s not caused by infection, and it’s not something that typically resolves in days. If the enlargement were persistent beyond a couple of years, or if a mass were unilateral, hard, or accompanied by other concerning signs, further evaluation would be warranted.