The fern test is used to aid the physician in the diagnosis of ruptured membranes by detecting the presence of amniotic fluid. This fluid, when placed on a glass slide, is allowed to dry.
What does a negative fern test mean?
Negative: No crystallization seen (membranes are not ruptured) Positive: Crystallization seen (membranes are ruptured)
What is fern test in medical terms?
[ fûrn ] n. A test for estrogenic activity in which cervical mucus smears form a fernlike pattern at times when estrogen secretion is elevated, as at the time of ovulation.
What does Ferning mean 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.
Can nurses test ferns?
Fern testing is intended for use by qualified medical and Allied Health Staff (e.g., advanced practice RNs and Physician Assistants) only as an aid to professional diagnosis and treatment. False-positive results: “Ferning” is not specific for amniotic fluid.
What pH is amniotic fluid?
Amniotic fluid normally has a pH of 6.5 or above whereas vaginal pH is 3.5–4.5.
How accurate is fern test?
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.
What causes a false positive fern test?
Well-estrogenized cervical mucus or a fingerprint on the microscope slide may cause a false-positive fern test; false negatives can be due to inadequate amniotic fluid on the swab or heavy contamination with vaginal discharge or blood.
Can a fern test be wrong?
Fern test has also 13-30% false negative and 5-30% false positive results (13, 14). “Several studies have been conducted to find a definite, easy, noninvasive and reliable diagnostic test for PROM in recent years” (18). These studies have mainly focused on biochemical agents with high concentration in amniotic fluid.
When is fern test done?
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’.
How does multiple pregnancy cause Polyhydramnios?
Abstract. Acute polyhydramnios in the second trimester is a typical complication in monozygous twin pregnancies. It is caused by a feto-fetal transfusion with anemia on the donor and polycythemia on the recipient twin. Contrary to the chronic hydramnios, there is no increase in malformations.
What causes Ferning pattern?
The crystallization patterns or ferning pattern are formed as a result of the higher levels of salt content in the dried saliva sample. The same patterns are detected in both saliva and cervical mucus samples.
What is fern phenomenon?
In 1945 Papanicolaou1 discovered the interesting phenomenon that cervical mucus spread on a slide and left to dry crystallized with “arborization,” a fern- or palm leaf-like reaction. He considered this phenomenon chracteristic of the time of ovulation.
How is a fern test performed?
Amniotic fluid contains a high amount of a salt called sodium chloride. If drops of the fluid are spread on a glass slide, allowed to dry, and examined through a microscope, a characteristic palm leaf pattern can be seen. This is why it is sometimes called “arborization” or the fern test.
Where do fern plants grow?
Ecologically, the ferns are most commonly plants of shaded damp forests of both temperate and tropical zones. Some fern species grow equally well on soil and upon rocks; others are confined strictly to rocky habitats, where they occur in fissures and crevices of cliff faces, boulders, and taluses.
