Nitrazine Test
This test involves putting a drop of fluid obtained from the vagina onto paper strips containing Nitrazine dye. The strips change color depending on the pH of the fluid. The strips will turn blue if the pH is greater than 6.0. A blue strip means it’s more likely the membranes have ruptured.
When is a nitrazine test performed?
All samples remained ferning and nitrazine positive. Therefore optimal analysis of suspected amniotic fluid occurs when specimens are air-dried for 10 minutes. These tests may be reliably performed at gestations of 12 to 41 weeks.
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 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.
How accurate is nitrazine test?
Kishida et al. reported the accuracy of the nitrazine test to be 62% (6). The tests that measure the pH of vaginal fluid are not specific and the interpretation of these tests are not trustworthy when the vaginal fluid is contaminated by blood, semen, urine or infectious discharge (7).
What is positive Amnisure?
The Amnisure ROM test™ is an immunoassay that detects high concentrations of PAMG-1 present in amniotic fluid. PAMG-1 is present in very low concentrations in blood or in cervicovaginal fluid when the membranes are intact.
Who performs a nitrazine test?
Only operators who have completed a defined training program and can demonstrate competence will be able to perform pH Nitrazine testing. Operator competency will be assessed annually by two methods.
Does amniotic fluid dry yellow?
Unlike actual yellow discharge, amniotic fluid is very thin and clear or pale yellow in color — like urine. And it’s usually odorless or slightly sweet-smelling.
How long can you stay pregnant with ruptured membranes?
Fetal membrane rupture has traditionally been regarded as an irreversible process: the mean latency period from membrane rupture to delivery is 12 days at 20–26 weeks of gestation and 4 days at 32–34 weeks of gestation (Parry and Strauss, 1998).
What is a nitrazine paper test used for?
Nitrazine (Phenaphthazine ) paper is used to measure the vaginal pH of expectant mothers. Nitrazine paper is impregnated with an indicator dye Phenaphthazine. The color changes as pH changes, giving a broad range of colors from yellow through blue.
What is thick meconium?
Meconium is a thick, green, tar-like substance that lines your baby’s intestines during pregnancy. Typically this substance is not released in your baby’s bowel movements until after birth. However, sometimes a baby will have a bowel movement prior to birth, excreting the meconium into the amniotic fluid.
What is Ferning amniotic fluid?
The arborization pattern found when a drop of amniotic fluid is allowed to air dry on a microscope slide, known as ferning.
What causes false positive nitrazine test?
Nitrazine paper will turn blue when the pH is above 6.0; however, the presence of contaminating substances (e.g., blood, semen, alkaline antiseptics) also can cause nitrazine paper to turn blue, giving a false-positive result. Bacterial vaginosis can produce a similar result.
How is PPROM diagnosed?
How is PPROM diagnosed?
pH (acid-base) balance testing. The pH balance of amniotic fluid is different from vaginal fluid and urine. Your healthcare provider will put the fluid on a test strip to check the balance.Looking at a sample under a microscope. When amniotic fluid is dry, it has a fern-like pattern.
What pH is amniotic fluid?
Amniotic fluid normally has a pH of 6.5 or above whereas vaginal pH is 3.5–4.5.
Can a nitrazine test be wrong?
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. Fern test has also 13-30% false negative and 5-30% false positive results (13, 14).
Does blood cause false positive Amnisure?
False positive results can be due to the presence of alkaline fluids in the vagina, such as blood, seminal fluid, soap, or some infections. Another confirmatory test is the presence of arborization (ferning).
How can I test amniotic fluid at home?
Place a sanitary pad or panty liner in your underwear and examine the fluid that is on the pad after 30 minutes to an hour. If the fluid is yellow in color, it’s likely urine. If it isn’t, the fluid could be amniotic fluid.
