The “Bag of Worms” Diagnosis: When a Teen Varicocele Needs Surgery and When It Doesn’t

Jacob was 15 when his mom brought him in to see me. A team physician had flagged something on his pre-season sports physical and used a phrase that understandably rattled both of them: it feels like a bag of worms. Jacob had no pain and hadn’t noticed anything himself. His mom had spent the previous week reading about it online and arrived convinced her son needed surgery, and soon.

I’m Dr. Justin Houman, a board-certified urologist and fellowship-trained specialist in Male Reproductive Medicine and Surgery — a subspecialty completed at UCLA and held by fewer than 2% of urologists nationwide. I’m an Assistant Clinical Professor of Urology at Cedars-Sinai and practice at Tower Urology in Los Angeles, where microsurgical varicocelectomy is among the procedures I perform most often. I mention it because the question Jacob’s mom was really asking — does my son need an operation? — deserves an answer from someone who does these every week, not a search result at midnight.

Here’s what I told her, and what I tell every parent who lands in my office after a physical: a varicocele in a teenager is common, usually not an emergency, and the right answer is very often to watch closely rather than operate. The skill is knowing which teenagers fall on which side of that line.

Why Teenage Boys Get Varicoceles in the First Place

A varicocele is a cluster of dilated veins in the scrotum — part of a network called the pampiniform plexus that drains blood from the testicle. When the tiny one-way valves in those veins fail, blood pools and the veins stretch, much like varicose veins in the leg. The result is that soft, ropey, bag-of-worms feeling, most often on the left.

The left-sided pattern isn’t random — it’s plumbing. The left testicular vein drains upward into the left kidney vein at a sharp angle and against gravity, making that side far more prone to backup. This is why a varicocele appearing only on the right, or one that doesn’t soften when a boy lies down, gets my full attention: rarely, it can signal something higher up in the abdomen pressing on those veins.

Varicoceles typically show up around puberty and are found in roughly 15% of adolescent boys, about the same rate seen in adult men — one of the most common findings in all of adolescent urology. Most of these boys feel completely fine, which is why so many are discovered by accident on a routine exam, the way Jacob’s was.

The Symptoms Most Teens Never Mention

The honest answer is that most teenage varicoceles cause no symptoms at all. When they do, the complaints I hear most often at my Los Angeles practice:

• Dull Scrotal Ache: A heavy or aching feeling, usually on the left side.
• Activity-Related Discomfort: Pain that worsens after long periods of standing, exercise, or a hot day.
• Relief When Lying Down: Discomfort that eases once he’s off his feet.
• Visible Veins: A cluster of veins that can be seen or easily felt through the skin.
• Size Difference: One testicle that looks or feels smaller than the other.

That last point matters most, and it’s the one a teenager is least likely to notice or bring up. A size difference between the two testicles is often the single most important clue in what happens next.

When Watching Is the Right Medical Call

For the majority of boys like Jacob, watchful waiting isn’t just acceptable — it’s the correct decision. If both testicles are growing symmetrically, he has no bothersome pain, and the rest of the exam is reassuring, there’s usually no reason to rush to the operating room. The varicocele itself isn’t dangerous, and operating on a testicle that’s developing normally exposes a healthy boy to surgical risk for no clear benefit.

Watching means active monitoring, though — not ignoring it. In my practice that’s a physical exam and a scrotal ultrasound (a painless imaging test that measures each testicle) every 6 to 12 months. We’re tracking one thing above all: are both testicles keeping pace as he grows? As long as they are, we stay the course, and many of these boys never need anything beyond reassurance and follow-up.

The Red Flags That Move Me Toward Repair

There are specific situations where I shift from watching to recommending treatment. I treat, or strongly consider treating, when I see any of the following:

• Growth Arrest or Hypotrophy: The testicle on the varicocele side is meaningfully smaller than the other, commonly a difference of about 20% or more on ultrasound that persists over time.
• Persistent Pain: Discomfort that interferes with daily life, sports, or sleep and doesn’t settle with conservative measures.
• Grade 3 Varicocele: A large varicocele easily visible through the skin.
• Bilateral Involvement: Varicoceles present on both sides.
• Abnormal Semen Analysis: In an older adolescent physically mature enough to provide one.

Growth matters so much because of fertility. In adolescents, a testicle falling behind in size is the earliest warning that the varicocele may be affecting how it works long term, and varicoceles are the most common correctable cause of male infertility. Treating the right teenager at the right time is about protecting his fertility decades before he thinks about starting a family. Every case is different, though, and not every boy with a varicocele is a surgical candidate — that’s the point of the evaluation.

Does Your Teenager Need a Semen Analysis?

This is a fair question from parents, and the answer depends on age and maturity. In younger adolescents, we rely on testicular size and growth instead. In older teens fully through puberty (Tanner stage 5), a semen analysis gives direct, objective information about testicular function and becomes one of the most useful tools we have. It’s simple and non-invasive, and when appropriate, it takes much of the guesswork out of the watch-versus-treat conversation.

How I Repair a Varicocele When It’s Warranted

When repair is the right call, my preferred approach is a microsurgical subinguinal varicocelectomy. Using an operating microscope, I tie off the affected veins through a small incision while carefully preserving the artery, lymphatic channels, and nerves. That magnification allows the precision, and the technique carries the highest success rates and the lowest rates of complication and recurrence compared with older methods. It’s an outpatient procedure, and most teenagers are back at school within days and back to full sports in a few weeks.

One of the most encouraging things I get to tell families is what often follows: in many adolescents whose affected testicle had fallen behind, we see catch-up growth once the varicocele is repaired. That’s exactly the outcome we’re trying to protect when we choose to treat.

What Happened With Jacob

Jacob’s exam and ultrasound were reassuring: a grade 2 varicocele on the left, no pain, and both testicles the same size and growing normally. He didn’t need surgery. He needed a plan. We scheduled a repeat exam and ultrasound in six months, I explained exactly what we were watching for, and I told him to come back sooner if he developed pain or noticed a change.

Over the next year and a half, everything stayed stable and symmetric. He never needed an operation, and his mom — who had walked in braced for surgery — left each visit reassured. That’s a good outcome too, and it only happens when a varicocele is watched properly rather than ignored or rushed into the OR.

What I Tell Every Parent Sitting Across From Me

First, take a breath. A varicocele is common, almost never an emergency, and finding one on a sports physical is not a crisis. Second, it isn’t something to simply forget about either. The value of a specialist evaluation is sorting the boys who can safely be watched from the smaller group who genuinely benefit from repair — then following the watchers closely enough to catch any change early. Third, the goal is nearly always the same: protect the growth and future function of that testicle so his fertility is preserved for a decision he won’t make for years.

The wrong moves are the two extremes. Operating on every varicocele exposes healthy boys to unnecessary surgery; dismissing it entirely risks missing the boy whose testicle is quietly falling behind. Be informed, not alarmed.

Talk With Dr. Houman About Your Son’s Varicocele

If your son has a varicocele, the most important step is an evaluation by a specialist who treats these every day and can tell you honestly which side of the treat-or-watch line he falls on. I care for families throughout Los Angeles, including Beverly Hills, West Hollywood, Santa Monica, and Culver City, and the first step is always a careful exam, the right imaging, and a straight conversation about what the findings mean for his future.

To schedule with Dr. Justin Houman, contact Tower Urology at 8635 W 3rd St, Suite 1W, Los Angeles, CA 90048, or call (310) 854-9898.