I Found a Lump on My Baby Boy's Testicle
The short answer
A lump or swelling in a baby's scrotum is most commonly a hydrocele (fluid collection) or inguinal hernia, both of which are benign and common. However, any new, firm, painless testicular mass should be evaluated by your pediatrician to rule out rare conditions including testicular tumors. Hydroceles transilluminate (glow when a light is shone through them), while solid masses do not. Most testicular masses in babies are benign, but prompt evaluation is important.
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By Age
What to expect by age
Hydroceles are very common in newborns - a painless, smooth swelling around the testicle that may change size. Most communicating hydroceles resolve by 12 months. Your pediatrician checks the testicles at every well visit. An inguinal hernia (bulge that increases with crying) needs surgical evaluation.
If a hydrocele has not changed by 12 months, surgical repair may be discussed. Any new hard lump in the testicle (not the surrounding fluid) should be evaluated urgently with ultrasound. Testicular torsion (twisted testicle) causes sudden severe pain and scrotal swelling and is a surgical emergency.
Testicular tumors, while rare, most commonly occur in the first 2 years of life. The most common type (yolk sac tumor) typically presents as a painless, firm testicular mass. Ultrasound can quickly distinguish between fluid (hydrocele) and solid mass (possible tumor).
Continue monitoring testicular size and symmetry at well visits. Undescended testicles that were not corrected by 12 months carry a slightly higher risk of testicular tumors. Any new firm, painless testicular mass should be evaluated promptly.
Testicular tumors remain rare but can occur. Teach your child to tell you if anything feels different or hurts. Any new testicular swelling or mass should be evaluated by your pediatrician.
What Should You Do?
When to take action
- A soft, painless scrotal swelling that transilluminates (hydrocele)
- Both testicles are similar in size and smoothly oval
- A hydrocele that fluctuates in size during the day
- You notice a firm lump on or within the testicle
- One testicle seems significantly larger than the other
- A hydrocele has not resolved by 12 months of age
- Sudden severe scrotal pain and swelling (possible testicular torsion - surgical emergency, go to ER immediately)
- A hard, rapidly growing testicular mass
Sources
Related Resources
Trust your instincts. If something feels wrong, reach out to your pediatrician.
Worrying about your baby means you care. That is a good thing.
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