The fingerprint, a false-positive fern test.
Microscope slides were prepared to confirm the presence of ferning from a 32-week gestation with possible premature rupture of the membranes. Although no amniotic fluid was seen in the vagina, an atypical ferning pattern was produced and was again reproducible with fingerprints on the glass slide. Guidelines to recognize and avoid this source of error are outlined.
Lodeiro
J G
JG
Department of Obstetrics and Gynecology, State University of New York Health Science Center, Syracuse.
Hsieh
K A
KA
Byers
J H
JH
Feinstein
S J
SJ
D000328:Adult; D000653:Amniotic Fluid / Q000032:analysis; D003878:Dermatoglyphics; D003937:Diagnosis, Differential; D003951:Diagnostic Errors; D005189:False Positive Reactions; D005260:Female; D005322:Premature Rupture of Fetal Membranes / Q000175:diagnosis*; D006801:Humans; D011247:Pregnancy; D012965:Sodium Chloride / Q000032:analysis; D014626:Vaginal Smears / Q000379:methods*
D012965:Sodium Chloride