What is a nitrazine pH test?
Nitrazine (Phenaphthazine) paper is used to measure the vaginal pH of expectant mothers to determine if the amniotic membrane has ruptured. The pH is used to determine if the fluid present represents amniotic fluid or vaginal fluid.
What does nitrazine positive mean?
Nitrazine Test A blue strip means it’s more likely the membranes have ruptured. This test, however, can produce false positives. If blood gets in the sample or if there is an infection present, the pH of the vaginal fluid may be higher than normal.
What is a nitrazine paper test used for?
Nitrazine (phenapthazine) paper is used to measure vaginal pH in two settings. 1. Assessment of membrane rupture in pregnant women as described in the Procedure for Premature Rupture of membranes (PROM) as found in the OB GYN Policy and Procedure Manual.
What is nitrazine and fern test?
Most studies investigating the usefulness of ferning and nitrazine methods for detecting the presence of amniotic fluid following ruptured amniotic membranes have employed samples from vaginal pooling. Reported accuracies are 84 to 100% for the ferning test and 87 to 97% for the nitrazine test.
What color is Nitrazine paper?
4. The color of undeveloped Nitrazine paper may vary from light yellow to an olive green color.
What is the pH of the amniotic fluid?
Amniotic fluid normally has a pH of 6.5 or above whereas vaginal pH is 3.5–4.5.
What is pH of amniotic fluid?
What color should Nitrazine paper turn with amniotic fluid?
Compare the color, which the moistened paper turns, to the standard color chart on the package of Nitrazine. Because amniotic fluid is neutral (pH 7.0) or slightly alkaline (pH 7.25), it will change the yellow color of Nitrazine Paper.
What Ferning means?
[ fûr′nĭng ] n. The formation of a fernlike pattern in a specimen of crystallized cervical mucus secreted at midcycle.
How do you test Nitrazine paper?
Procedure:
- Add one drop of buffer to Nitrazine test paper.
- Compare color to the paper dispenser’s pH scale. The pH must be within 0.5 of the designated pH to be acceptable.
- Document all results on the Control Sheet. If controls are out of range do not report any patient results until corrective action has been taken:
What pH is amniotic fluid?
What is Ferning in pregnancy?
The American College of Obstetricians and Gynecologists says that ferning is a confirmatory test for ruptured membranes, to be used along with pooling in the vaginal vault, and that premature membrane rupture is confirmed by fluid passing from the cervical canal.
What colour is amniotic fluid?
Normal amniotic fluid is clear or tinted yellow. Fluid that looks green or brown usually means that the baby has passed the first bowel movement (meconium) while in the womb.
How do you use Nitrazine paper for amniotic fluid?
Bring the strip of Nitrazine paper into contact with the specimen, either by dipping the paper into the pool of suspected amniotic fluid or by touching the paper to the exam speculum.
What is a positive fern test?
The proteins and saline content of amniotic fluid crystallize on a slide when dry yielding the appearance of ferns. A positive test shows the presence of fern-like patterns characteristic of amniotic fluid crystals.
What causes Ferning?
When high levels of estrogen are present, such as just before ovulation (or during pregnancy), the cervical mucus forms fern-like patterns due to crystallization of sodium chloride on mucus fibers. This pattern is known as arborization or ‘ferning’.
What color does Nitrazine paper turn with amniotic fluid?
Because amniotic fluid is neutral (pH 7.0) or slightly alkaline (pH 7.25), it will change the yellow color of Nitrazine Paper. The pH values of blood, vaginal mucus, and certain secretions form vaginal infections are also Page 5 Procedures 5 Sterile Speculum Exam Policy and Procedure (con’t) alkaline.
How accurate is nitrazine paper?
The diagnosis of rupture of the membranes by traditional methods of nitrazine paper determination and fern crystallization has been reported to be 93-98% accurate. Although the presence of contaminants in amniotic fluid has been reported to reduce this accuracy, the literature is conflicting concerning these effects.
What is PROM in pregnancy?
Premature rupture of membranes (PROM) is a rupture (breaking open) of the membranes (amniotic sac) before labor begins. If PROM occurs before 37 weeks of pregnancy, it is called preterm premature rupture of membranes (PPROM).
What is the difference between NST and CST?
The NST (with or without amniotic fluid assessment) has become the preferred antepartum test of fetal oxygenation status because the CST, which usually requires stimulation of uterine contractions, is more time-consuming, more invasive, and more limited by contraindications than the NST.
What is reactive NST?
A NST is considered reassuring if the fetal heart rate increases at least 15 beats per minute over the baseline (between 120 and 160 beats per minute), lasting at least 15 seconds, within a 20-minute timeframe. This is called a “reactive NST.”
What can cause false positive nitrazine?
However, a nitrazine test can give a false positive result if the sample is contaminated with blood, semen or antiseptics, or if the patient has vaginitis or cervicitis.
Does blood affect nitrazine?
Nitrazine test may also lead to false positive or negative results due to probable contamination by alkaline urine, semen, blood, meconium, vaginitis, cervicitis and using antibiotics.