Evaluation of semen detection in vaginal secretions: comparison of four methods.
OBJECTIVE
To determine the best method to detect semen in human vaginal secretions.


METHODS
Vaginal secretions from 302 pregnant women at mean 11.8 weeks' gestation were analyzed. Semen detection was assessed with: (i) measurement of total prostate-specific antigen (PSA), (ii) acid phosphatase activity, (iii) microscopic measurement of spermatozoa on Gram stain, and (iv) self-reported sexual intercourse in the past 2 days. Sensitivity and specificity were calculated for each technique in comparison with PSA levels.


RESULTS
A total of 119 (39.4%) women had a detectable PSA. Compared with measurable PSA, the sensitivity and specificity for other methods were: acid phosphatase (26.9%, 98.4%), Gram stain (36.1%, 98.4%), and self-report of intercourse in the past 48 hr (41.9%, 88.8%).


CONCLUSIONS
Compared with PSA levels, commonly used assays for recent semen exposure are inaccurate. This inaccuracy may affect the results of studies, which measure vaginal immune factors like cytokines or retrieve DNA from vaginal specimens.
Culhane
Jennifer Flatow
JF
Department of Obstetrics and Gynecology, Drexel University College of Medicine, Philadelphia, PA, USA.
Nyirjesy
Paul
P
McCollum
Kelly
K
Casabellata
Giorgia
G
Di Santolo
Manuela
M
Cauci
Sabina
S
D000135:Acid Phosphatase / Q000032:analysis*; D000328:Adult; D001826:Body Fluids; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods*; D008297:Male; D017430:Prostate-Specific Antigen / Q000032:analysis*; D012661:Semen; D012680:Sensitivity and Specificity; D011795:Surveys and Questionnaires; D014621:Vagina / Q000378:metabolism*
D000135:Acid Phosphatase; D017430:Prostate-Specific Antigen