Inguinal hernia and hydrocele
Assess groin and scrotal swelling correctly, recognize incarceration, and know which child needs surgery and when.
Step 1 of 10
Objectives
After this course you will be able to
- Explain the common cause of inguinal hernia and hydrocele in children.
- Distinguish a hernia from a hydrocele clinically.
- Recognize an incarcerated hernia and know the first steps.
- Choose the timing of surgery according to age and situation.
- Know when a hydrocele is observed and when it is operated on.
Key message: an inguinal hernia in a child does not resolve on its own and, because of the risk of incarceration, is repaired without much delay after diagnosis. A simple hydrocele, by contrast, resolves on its own in most infants by 1–2 years.
Basics
In numbers
- 1–5%hernia in term infants
- much higherin preterm infants
- ~6:1male to female ratio
- ~60%right-sided
In children, an inguinal hernia is almost always indirect: the processus vaginalis formed during testicular descent fails to close, and bowel, omentum or, in girls, the ovary herniates from the abdominal cavity into this canal.
When the canal is narrow, only fluid passes through and a communicating hydrocele develops. Same anatomic problem, different clinical picture.
Basics
The spectrum: from hernia to hydrocele
| Condition | Processus vaginalis | Clinical picture |
|---|---|---|
| Inguinal hernia | Widely patent | Swelling that appears with crying and goes back when the child is calm |
| Communicating hydrocele | Narrowly patent | Size changes during the day: small in the morning, large in the evening |
| Noncommunicating hydrocele | Closed | Stable size, soft, painless; often resorbs |
| Spermatic cord cyst | Remains open in the middle segment | Small, mobile cyst along the cord above the testicle |
| Abdominoscrotal hydrocele | Sac extending into the abdomen | Very large, the scrotum tenses with abdominal pressure; rare, early surgery |
Diagnosis
Hernia or hydrocele?
- Can you palpate the upper border of the swelling? The upper border of a hydrocele is palpable, while a hernia extends into the inguinal canal.
- Does it reduce? A hernia often goes back with pressure or when the child calms down.
- Does the size change? A hydrocele that changes size during the day is communicating.
- Is the testicle palpable separately? A tense hydrocele can hide the testicle.
- A photo or video taken by the parents is very useful: the hernia may not be visible during the examination.
Do not rely fully on transillumination: in infants a bowel loop can also transilluminate.
The diagnosis is usually clinical. Ultrasound is needed only in doubtful cases, when the testicle is not palpable, or for a new hydrocele in an adolescent.
Diagnosis
Incarcerated hernia
The herniated organ does not return and its blood supply is compromised. The risk is highest in the first year of life, especially in preterm infants.
- Firm, painful, irreducible swelling.
- Inconsolable crying, vomiting, abdominal distension.
- In late stages, redness, bluish discoloration, signs of bowel obstruction.
- An incarcerated hernia can also compromise the blood supply of the testicle.
- Suspected incarceration
- Urgent surgical assessment
- Careful manual reduction with analgesia
- If successful, surgery within 24–72 hours
- If unsuccessful or signs of peritonitis, emergency surgery
Diagnosis
Hernia in girls
- Hernias are less common in girls, and the sac often contains the ovary.
- An irreducible ovary requires prompt surgery because of the risk of torsion and ischemia.
- Rarely, a testicle is found in the hernia sac: this may be complete androgen insensitivity syndrome (46,XY). This possibility should be considered in girls with bilateral hernias.
Treatment
Timing of hernia repair
| Situation | Recommendation |
|---|---|
| Term infant or child, reducible hernia | Elective surgery soon after diagnosis (within a few weeks) |
| After an incarceration episode with manual reduction | Within 24–72 hours, once the edema has subsided |
| Preterm infant in the neonatal intensive care unit | Individual decision; in a randomized trial (HIP), deferring surgery until after discharge was associated with fewer serious adverse events |
| Irreducible ovary in a girl | Prompt surgery |
A truss or belt does not treat a hernia in children and does not prevent incarceration. It is not recommended.
Treatment
Surgical techniques
Open herniotomy: through a small incision in the groin crease, the sac is identified, separated from the spermatic cord and ligated high. Mesh is not used in children.
Laparoscopic technique: the internal inguinal ring is closed from inside the abdomen; the contralateral side is inspected at the same time and can be closed if patent.
Both techniques are safe and results are similar. Routine contralateral exploration is not recommended with the open technique.
Preterm or anemic infants are at risk of postanesthetic apnea. Such infants are monitored after surgery.
Treatment
Management of hydrocele
| Situation | Approach |
|---|---|
| Simple hydrocele of stable size | Observation until 12–24 months |
| Communicating hydrocele (changing size) | Surgery; it can turn into a hernia |
| Hydrocele persisting after 2 years | Surgery |
| Very large, tense, abdominoscrotal hydrocele | Earlier surgery |
| New hydrocele in an adolescent | Ultrasound first: tumor, torsion, inflammation, hydrocele after varicocele surgery |
Unlike in adults, hydrocele surgery in children is performed through an inguinal approach: the patent canal is closed. The fluid is not aspirated with a needle: it reaccumulates and there is a risk of infection.
The pediatrician's role: distinguish a hernia from a hydrocele, refer a child with a hernia without losing time, teach parents the signs of incarceration, and avoid unnecessary early surgery for a simple hydrocele.
Quiz
Quiz: Inguinal hernia and hydrocele
Test yourself: choose one answer.
-
A 3-month-old term boy has a right groin swelling that appears when he cries and goes back when he calms down. What is the most appropriate approach?
A hernia in a child does not resolve on its own, and infants have a high risk of incarceration. Surgery is performed without much delay after diagnosis.
-
An 8-month-old has a soft, painless scrotal swelling of stable size, with a palpable upper border. What should be done?
This is a noncommunicating (simple) hydrocele. Most resorb on their own by 1–2 years.
-
What does a scrotal swelling that is small in the morning and grows in the evening and with crying indicate?
A change in size during the day indicates a patent processus vaginalis. Such a hydrocele requires surgery and can turn into a hernia.
-
A groin swelling has become firm and painful, and the infant is vomiting. What is the first step?
This is an incarcerated hernia. Urgent surgical assessment is needed: if reduction succeeds, surgery within 24–72 hours; if it fails, emergency surgery.
-
During surgery in a girl with bilateral inguinal hernias, a gonad that does not look like an ovary is found in the sac. What should be considered?
A testicle in the hernia sac of a phenotypic girl suggests complete androgen insensitivity syndrome (46,XY). A karyotype and endocrinology consultation are needed.
Course completed
Related articles for parents
Sources
- EAU Guidelines on Paediatric Urology, 2025: Hydrocele.
- HIP Trial Investigators. Early vs late inguinal hernia repair in preterm infants: a randomized clinical trial. JAMA. 2024.
- Olesen CS, Mortensen LQ, Öberg S, Rosenberg J. Risk of incarceration in children with inguinal hernia: a systematic review. Hernia. 2019;23(2):245–254.
This material is intended for medical professionals and is based on current clinical guidelines. Decisions about an individual patient are made by the treating doctor.