Pelvic Exam Findings in Suspected PPROM
During a pelvic exam for suspected PPROM, you are primarily looking for pooling of amniotic fluid in the posterior vaginal fornix, purulent or discolored cervical discharge indicating infection, and assessing cervical dilation—while avoiding digital cervical examination to minimize infection risk. 1
Primary Diagnostic Findings
Perform a sterile speculum examination (never digital cervical exam initially) to identify:
- Pooling of clear or blood-tinged fluid in the posterior vaginal fornix during speculum examination, which is the most direct visual confirmation of membrane rupture 2, 3, 4
- Fluid leakage from the cervical os, particularly when asking the patient to Valsalva or cough during the examination 2, 3
- Nitrazine-positive fluid (pH >6.0, turns blue) collected from the pooled fluid, though this can have false positives from blood, semen, or bacterial vaginosis 2, 4
- Ferning pattern when vaginal fluid is placed on a slide and air-dried under microscopy, representing crystallized amniotic fluid salts 2, 3, 4
Critical Signs of Infection to Assess
Evaluate for signs of intraamniotic infection, which occurs in 38% of expectant management cases and may present without fever, especially at earlier gestational ages 1:
- Purulent or malodorous cervical discharge indicating ascending infection 5, 1
- Uterine tenderness on abdominal palpation during or after the speculum exam 5, 1
- Maternal tachycardia (>100 bpm) as an early sign of infection 5, 1
- Maternal fever ≥38°C, though absence of fever should NOT delay diagnosis of infection as clinical symptoms may be subtle initially 5, 1
What NOT to Do
- Avoid digital cervical examination unless the patient is in active labor or delivery is imminent, as this increases infection risk and shortens latency period 6, 3
- Do not delay assessment for infection based on absence of fever alone, as infection can progress rapidly with median time to death of only 18 hours in severe cases 1, 7
Additional Assessment During Speculum Exam
- Assess for vaginal bleeding suggesting placental abruption, which occurs more frequently with PPROM and requires immediate delivery consideration 1, 6
- Visualize the cervix for dilation and effacement without digital examination 3
- Collect vaginal and rectal swabs for Group B Streptococcus culture during the same speculum exam 3
Equivocal Cases
When clinical findings are unclear (no visible pooling, negative nitrazine/ferning):
- Consider biochemical tests such as placental alpha macroglobulin-1 (AmniSure) or IGFBP-1/AFP tests, which have higher sensitivity and specificity than traditional bedside tests 2, 3
- Ultrasound assessment of amniotic fluid volume can support the diagnosis but should not be used alone, as oligohydramnios has multiple causes 3, 8