Sharp Diaphragmatic Pain in Early Pregnancy
While sharp diaphragmatic pain in early pregnancy can represent benign musculoskeletal or gastrointestinal causes, you must urgently exclude life-threatening diaphragmatic hernia, which can present with nonspecific symptoms and lead to catastrophic maternal-fetal outcomes if missed. 1
Immediate Clinical Assessment
Obtain a focused history specifically asking about:
- History of trauma (even remote) or previous abdominal/thoracic surgery 2
- Associated dyspnea, chest pain, or respiratory distress 2, 1
- Severe or progressive epigastric pain with distension 3
- Intractable vomiting (hyperemesis can cause diaphragmatic tear) 3
- Sudden onset with "popping" sensation in abdomen 4
- Collapse or near-syncope episodes 1
Physical examination must document:
- Vital signs including oxygen saturation (hypotension and tachycardia may be masked by pregnancy's physiologic changes) 4
- Respiratory rate and work of breathing 2
- Peritoneal signs (guarding, rigidity, rebound tenderness) 5, 6
- Auscultation for bowel sounds in chest 7
Critical Differential Diagnosis
Diaphragmatic hernia (DH) is the most dangerous diagnosis to exclude because:
- It presents with nonspecific symptoms easily confused with common pregnancy complaints 1
- Presentation less than 3 days carries significant risk of strangulation 1
- Maternal and fetal mortality increase dramatically with delayed diagnosis 1, 7
- 50% of cases are initially misdiagnosed 1
Other serious causes include:
- Ruptured ectopic pregnancy (if truly early pregnancy with positive β-hCG) 5
- Appendicitis (most common non-obstetric surgical emergency in pregnancy) 5, 6
- Splenic or hepatic injury if any trauma history 5
Diagnostic Algorithm
For pregnant patients with suspected diaphragmatic pathology, ultrasonography is the first-line imaging study 2. However, recognize that:
- Chest X-ray has low sensitivity (2-60% for left-sided, 17-33% for right-sided DH) 2
- Normal imaging does NOT exclude diaphragmatic hernia 2
If ultrasound is non-diagnostic and clinical suspicion remains high, proceed to MRI 2. The 2023 World Society of Emergency Surgery guidelines specifically recommend this sequence in pregnant patients with suspected non-traumatic DH 2.
Do not delay imaging due to radiation concerns - maternal and fetal outcomes worsen significantly with delayed diagnosis 6, 1.
Management Strategy
If diaphragmatic hernia is confirmed or strongly suspected with any of the following, immediate surgical consultation is mandatory:
- Evidence of organ strangulation (severe pain, hemodynamic instability, peritoneal signs) 1, 7
- Respiratory compromise 1, 7
- Cardiovascular collapse 1
Strangulated diaphragmatic hernia requires emergency operative repair regardless of gestational age 1, 7. The consensus from systematic review shows that hernias with strangulation mandate immediate surgery, with delivery based on obstetric indications rather than routine cesarean 1, 7.
For asymptomatic or minimally symptomatic hernias detected incidentally:
- Consider elective repair in second trimester 7
- Close monitoring if conservative management chosen 7
- Vaginal delivery only under closely monitored conditions if hernia present at term 7
Critical Pitfalls to Avoid
Never attribute severe or progressive diaphragmatic pain to "normal pregnancy changes" without excluding serious pathology 6. The physiologic changes of pregnancy (increased intra-abdominal pressure, elevated diaphragm, altered anatomy) can both mask and exacerbate diaphragmatic pathology 8, 1.
Do not dismiss intractable vomiting with severe epigastric pain as simple hyperemesis gravidarum - this combination can indicate diaphragmatic tear from forceful vomiting 3.
Clinical judgment must supersede negative imaging when suspicion is high, as diaphragmatic hernias are frequently missed on initial imaging 2, 1.
When to Reassure
If comprehensive evaluation (including appropriate imaging) excludes structural pathology and the patient has:
- Mild, intermittent pain without red flags
- Normal vital signs and oxygen saturation
- No respiratory symptoms
- Normal imaging
Then musculoskeletal pain from ligamentous stretching or costochondritis becomes more likely. However, maintain low threshold for re-evaluation if symptoms progress 8.