II. Indications
- Evaluation for Premature Rupture of Membranes
III. Mechanism
- Nitrazine Paper relies on Prussian blue reaction
- Requires alkaline paper to cause reaction
IV. Technique
- Obtain fluid for exam (usually after Vaginal Pooling)
- Place Nitrazine Paper in fluid
- Paper turns bright blue in alkaline fluid
V. Interpretation: Nitrazine Paper
- Normal Vaginal pH 4.5-6.0
- Paper does not change color
- Ruptured Vaginal pH 7.1-7.3
- Suggests PROM (paper blue)
VI. Causes: False Positive Nitrazine positive (pH >7)
- Blood
- Semen
- Antiseptic solutions
- Urine with increased pH (alkaline urine)
- Vaginal infection or Cervicitis (e.g. Bacterial Vaginosis)
VII. Efficacy
- Test Sensitivity: 90-97%
- Test Specificity: 70% (as low as 16% in some studies)