II. Indications
- Evaluation for Premature Rupture of Membranes
III. Technique
- Obtain fluid for exam (usually after Vaginal Pooling)
- Place sample on glass slide
- Allow sample to air dry for 10 minutes
IV. Interpretation
- Slide shows Ferning pattern under microscopy
V. Efficacy
- Test Sensitivity: 98% when in labor (51% if not in labor)
- Test Specificity: 88% when in labor (70% if not in labor)
VI. Differential Diagnosis
-
False Positive for Ferning
- Cervical Mucus
- Semen
-
False Negative for Ferning
- Slide not allowed to dry 10 minutes
- Swab dry
- Contamination with blood