A hernia occurs when an organ or fatty tissue pushes through a weak spot in the surrounding muscle or connective tissue, often creating a visible bulge in the abdominal wall or groin area. For individuals planning a pregnancy while having a known hernia, the decision of whether to undergo surgical repair beforehand involves careful consideration of risks and benefits. The physiological changes of pregnancy can significantly affect a pre-existing hernia, potentially increasing discomfort or leading to serious complications.
How Pregnancy Affects Existing Hernias
Pregnancy creates an environment that naturally strains the abdominal wall, which can easily exacerbate a pre-existing hernia. The most significant factor is the massive increase in intra-abdominal pressure caused by the growing uterus and developing fetus. This pressure pushes against the weakened point in the muscle or fascia, often causing the hernia to enlarge and become more noticeable or symptomatic.
Hormonal changes also play a role in weakening the abdominal structure. The hormone relaxin is released during pregnancy to soften and widen the cervix and relax pelvic ligaments. It also causes a general laxity in connective tissues, including the fascia around the hernia defect. This tissue softening can make the hernia defect less stable and more prone to protrusion. The most common hernias affected by these changes are umbilical (near the navel) and inguinal (in the groin).
The enlargement and pressure increase the potential for the hernia contents to become trapped, a complication known as incarceration. An incarcerated hernia cannot be easily pushed back into the abdomen and often causes increased pain and discomfort. While many hernias remain stable throughout pregnancy, the risk of incarceration and the more dangerous strangulation—where blood supply to the trapped tissue is cut off—is the primary concern.
Factors Guiding the Timing of Repair
The timing of surgical repair is determined by the hernia’s size, location, and symptom severity. For small, asymptomatic hernias, postponing the repair until after childbirth is often the preferred strategy, as this avoids the risks associated with surgery during pregnancy. However, if a hernia is causing pain, is rapidly increasing in size, or is highly symptomatic, an elective repair should be considered before conception.
Elective pre-pregnancy repair offers the advantage of eliminating the risk of hernia-related complications during pregnancy itself. It also allows surgeons to use a synthetic mesh to reinforce the repair, which is the standard technique for reducing recurrence. This repair should ideally be performed at least 6 to 12 months before conception to allow for complete healing and stabilization of the abdominal wall. While mesh repair is often recommended due to the high recurrence rate of simple suture repairs, some evidence suggests mesh may restrict abdominal wall flexibility and cause pain in a subsequent pregnancy.
Urgent or emergency surgical repair is mandatory if the hernia shows signs of acute complications, regardless of pregnancy status. Signs of incarceration or strangulation—such as sudden, severe pain, an inability to push the bulge back, or signs of bowel obstruction—mean that surgery must be performed immediately to prevent tissue death. If the hernia remains small and asymptomatic throughout the pregnancy, the recommendation is to defer definitive repair until 3 to 6 months postpartum. Repairing the hernia at the time of a planned Cesarean section is possible for some umbilical hernias, but this approach may be associated with a higher risk of recurrence compared to a repair performed months later.
Non-Surgical Management and Emergency Signs
When surgery is deferred, non-surgical management focuses on reducing pressure on the hernia site and managing discomfort throughout the pregnancy. Avoiding activities that involve heavy lifting or straining minimizes stress on the abdominal wall defect. For women with umbilical hernias, a supportive maternity belt or abdominal binder may be recommended to provide external support and relieve pressure.
Managing weight gain within the recommended range for pregnancy also helps limit increased intra-abdominal pressure. Gentle manipulation of the hernia, such as pushing the bulge back in while lying down, can sometimes relieve symptoms, but this should only be done if the hernia is reducible and with a doctor’s guidance.
It is imperative for women managing a hernia during pregnancy to be aware of the specific signs that signal an immediate medical emergency, indicating incarceration or strangulation. Urgent intervention is required if the following symptoms occur:
- Sudden onset of severe pain at the hernia site, especially if accompanied by nausea or vomiting.
- Inability to push the hernia bulge back in.
- A noticeable change in the skin over the hernia, such as redness or darkening.
- Fever or an increased heart rate, which suggests the trapped tissue is losing its blood supply.