Prostatic acid phosphatase and sperm in the post-coital vagina

Area of Science:

• Forensic Science
• Biochemistry
• Gynecology

Background:

• Sperm and prostatic acid phosphatase in vaginal fluid are crucial forensic evidence in sexual assault cases.
• Establishing normal and abnormal ranges for vaginal acid phosphatase is vital for emergency departments.
• Comparing the sensitivity of acid phosphatase and sperm detection for recent coitus is necessary.

Purpose of the Study:

• To define normal and abnormal ranges for post-coital vaginal acid phosphatase.
• To compare the sensitivity of acid phosphatase versus sperm identification in determining recent intercourse.

Main Methods:

• Analysis of vaginal swabs from 90 patients for acid phosphatase activity using the Sigma p-nitrophenyl phosphate technique.
• Storage of swabs in bovine albumin preservative broth.
• Performance of Pap smears for sperm identification.

Main Results:

• Acid phosphatase values >50 Sigma units/cc correlated significantly with intercourse within 24 hours (P < .005).
• Values between 20-50 Sigma units/cc correlated significantly with intercourse within 48 hours (P < .005).
• Sperm identification was less sensitive and correlated poorly with time since intercourse compared to acid phosphatase.

Conclusions:

• Elevated vaginal acid phosphatase levels are a reliable indicator of recent sexual activity.
• Acid phosphatase testing demonstrates higher sensitivity than sperm detection for establishing recent coitus.
• This study provides valuable reference ranges for acid phosphatase in forensic and clinical settings.