Our objective was to evaluate the ability of a pad containing an immunoassay for alpha-fetoprotein (AFP) to detect amniotic fluid (AF) leakage to serve as a rapid and simple one-step bedside test.
A prospective cohort study. Pads containing a qualitative immunoassay for AFP (detection threshold of 20 ng/mL) were used. The study group was pads worn by 200 pregnant women with confirmed rupture of membranes. Three controls were evaluated: 1) Pads worn by 70 pregnant women with intact membranes who had no vaginal bleeding; 2) Additional pads instilled with urine specimens obtained from the 270 women described above (200 cases and the 70 women in group 1); 3) Pads instilled with semen collected from 40 men seen in an infertility clinic.
All 200 pads that absorbed AF had positive results. Among the pads from the 70 women with intact membranes, only 36 absorbed a sufficient amount of normal vaginal discharge to activate the colorimetric reaction, and they all had negative results. The colorimetric reaction was either not activated or failed to complete in the remaining 34 pads. All 270 pads that absorbed urine, and all 40 pads with semen, had negative results.
A qualitative immunoassay for AFP, embedded in a pad, appears to be a reliable bedside test for distinguishing amniotic fluid leakage from normal vaginal discharge, urine, or semen. This assay, based on the same principle as a home urine pregnancy test, has the potential to be a rapid and simple one-step bedside or home test for ROM.
Maimonides Medical Center, Brooklyn, NY
Financial Disclosure: The authors did not report any potential conflicts of interest.