Facts About Semen Detection ] [ FAQ Semen and Sperm ] [ FAQ Underwear ] [ Types of Samples ]

Frequently Asked Questions About Semen Detection

There is semen on my wife’s panties and it’s not mine, how do I test it?

FAQ on Semen, Sperm, and Vaginal Discharge     FAQ on PSA vs. AP     Infidelity DNA Test

Having tested hundreds of non clothing items for semen such as shower drains, wood chips, carpet, condoms, pizza, hair, spit in baggies and cups, finger wiping on tissues, floors, combs and brushes, food wrappers, feminine pads and tampons, band aids, fistulas from medical procedures, bed linens, bed posts, wash cloths and towels, tooth brushes, just to name a few, these items account for a fraction of the number of tests performed on underwear.  All items above account for less than 2% of  the items we test.

Ninety-eight percent (98%) of our serology tests were performed
on panties, feminine pads and male underwear

SSDI is the most experienced private serology test lab for infidelity testing.  We remain on the forefront of technology by developing new products and processes.  Having developed the first non-presumptive semen detection kit in 2002 to our current validation of a specific sperm protein marker to specify the presence of sperm in a sample (even when badly degraded), you are guaranteed the most accurate and conclusive testing available.

Do any of our competitors offer any type of superior serology or DNA test?

Absolutely not – We guarantee you the most accurate, sensitive, and expedited test. No other lab offers the combination of testing procedures which are included at no additional cost. Semen, Sperm, Saliva testing is included on every sample.  Our proprietary process was developed over several years and is unique and all-encompassing.  Panties and feminine pads that test positive for semen include the time frame of copulation.  Male underwear tests include pre-cum or ejaculation occurrence and specific DNA recommendations and blood detection is included on every pair of male underwear or when otherwise warranted. Sperm protein testing is included on positive samples where sperm is expected to be present but could not be found by microscopic inspection (due to degraded sperm usually caused by age or method of storage). DNA testing is available by PowerPlex, YPLEX,  or mtDNA direct sequencing.  Extractions include DNA IQ, Puregene, Differential Lysis, and MtDNA gel extractions, to name a few.  DNA uses and capabilities can be further investigated at this link.

I think my spouse is cheating on me.  What do I do?

See this link for signs of infidelity.  Abstain from having intercourse with him/her for 5-7 days. Order a laboratory semen/sperm/saliva detection and mail in her panties or his underwear to:

110 East Broward Blvd Suite 1700
Fort Lauderdale, Florida 33301

My husband is accusing me of having an extramarital affair affair.  What do I do?

See this link for how we can help you. Order a laboratory semen/sperm/saliva detection and mail in your panties or feminine pad to:

110 East Broward Blvd Suite 1700
Fort Lauderdale, Florida 33301

How do I package the item?

Most panties will fit in a #10 envelope. Most male underwear will fit in a 6×9 envelope or a paper bag. Let cloth samples dry at room temperature before sending. Mark each envelope or bag the following (when available):

Description of item
Date worn
Date obtained

If you are sending in your wife’s panties, specify if you are a potential contributor and any useful information such as when was the last time you had ejaculated in her, and if you have had a vasectomy. If you are sending in your husband’s underwear, specify if you are a potential contributor (from intercourse or handling of the stains) and any useful information, such as if he has had a vasectomy. Do not place any paperwork in the same envelope or bag holding the article. Due to cross-contamination issues, the paperwork will not get read until the test is underway. Detail your thoughts and information.  We have tested many articles where the spouse admits later that the article was licked to try to determine the content of the stains.  We need this information. Many items contain evidence of home semen tests.  Provide the name of this test on your envelope or bag.

How do I know if I need a                          legal or non-legal test?

Most customers order non-legal testing.  There are no special handling requirements and you can still provide your family, attorney, or judge with the results.  We have done hundreds of non-legal cases for Private Investigators and Attorney’s. Individuals needing a legal test, normally Attorneys representing a client, Private Investigators on surveillance, Forensic Companies, Police, and Government Laboratories,  in anticipation of submission of the evidence in a court of law (normally criminal requiring expert witness testimony).  These evidence submission requirements are necessary for your case to be treated as legal:

A general chain of custody or the transfer of the chain of custody.
An exhibit submission form authorizing the test and return of evidence (PDF with form fields).

How old of a sample can you test?

The sample can be any                   age.  There is data supporting 30 year old samples testing positive for semen. Place any sample in a brown paper bag or paper envelope. Mark the sample envelope with the date the item was worn or the date the sample was obtained if not worn (when possible). Store cloth samples at room temperature until testing is required. Positive test results will include this date (when provided) and the results on panties and feminine pads will specify when the intercourse most likely took place.

I purchased a laboratory test from a different company and am not satisfied with the results. What can I do?

We will review any semen detection report for free and provide suggestions.  Email your report to Info@Semen-Detection.com.  Make sure you do more than just an AP home test which is meaningless alone. It is also very important not to do DNA testing alone.  You need to have documented proof that the tested item contains semen, sperm, saliva, or blood.

Why are you the only private lab offering saliva detections as part of your semen detection?

Only government crime labs have the capability and experience to perform this test (besides SSDI).  We integrated the infidelity saliva test as part of our semen detection in 2007. We have many cases where the suspect is caught by positive saliva results when the semen detection test was negative.  See our testing report section for details on the outcome of many tests including negative semen detections where human saliva is detected and proven by a DNA analysis to be from a male (not the husband). We are the only private company including saliva detections as part of every semen detection test.

I ran a home Prostate Specific Antigen (PSA) test and got positive results. Are these results the best outcome?

We recommend that you do not let the outcome of any home semen detection test result in a life changing situation (such as a divorce).  If you confront your spouse before you have 100% conclusive results you will jeopardize your relationship. Low confidence on a home test?  Have four different tests run by experienced professionals for only $245.00 that includes the most reliable and sensitive PSA test, an acid phosphatase test which indicates how much of the stain is semen, a microscopic inspection for sperm, and a human saliva detection test. Select this link for one of the follow-up tests which provide DNA profiling.  Please review actual test reports which can assist in your decision.

I ran a home Acid Phosphatase (AP) test (purple or blue dye test) and got positive results. Are these results the best outcome?

Confirm that it is semen with a home PSA kit or our laboratory test. AP tests are presumptive and a false positive or negative can occur.  Three percent of all AP tests produce a false positive as demonstrated by our statistics. If it is remotely possible that the questionable stain is from your semen, perform a DNA confirmation test. Home AP tests are often mislabeled as accurate and reliable.  See our frequently asked questions section about the difference between our tests and AP scams.  The reason we classify an Acid Phosphatase (AP) test as a scam is because the significant majority of internet websites do not identify an AP kit as presumptive.  Some websites even classify a home AP kit as 100% accurate.  Every website selling AP kits should tell you that you can receive false positive and negative results.  Here is our home AP kit page as an example.

I ran a home AP test and got negative results. Are these results the best outcome?

False negatives are common with home AP kits.  AP is detected only up to 72 hours after intercourse.  Thirty-five percent of our lab AP tests produce a false negative as demonstrated by our validation study and statistics. If you have not had intercourse for 7 days or more, you should consider our laboratory testwhich will provide 100% accurate and conclusive results and is the most sensitive semen detection available.

I was told that a black (UV) light could be use to detect a semen stain. Is that true?

A black light can be helpful in locating biological stains for testing. No expert can look at a random set of stains and tell you which one is semen. We use an expensive selectable multi-band UV forensic lamp to fluoresce each article before the extraction is accomplished so that we obtain sampling from every stain.  Then we follow that with another unit that provides an exact 450 nm wavelength, combined with special orange glasses, which makes invisible semen stains visible. The $10 black lights sold on the internet are better than nothing…but not much.  If you are getting one free with your home kit, expect the cost to the supplier to be between $2.50 and $5.00.

I purchased a SSDI laboratory test with positive results or I am 100% positive I have semen/sperm from another lab or PSA home test. How do I identify the male contributor when the sample (such as tissue or garment) I have consists of semen/sperm only and was not contaminated by the female presence (such as vaginal discharge from panties or a feminine pad)?

You would order a PowerPlex DNA extraction from semen/sperm or the complete PowerPlex sperm determination.

How do I identify the male contributor when the sample (such as panties or feminine pad) consists of semen/sperm and probable contamination from a female but I am only trying to identify the male contributor?

You would order a YPLEX DNA extraction from semen/sperm or the complete YPLEX sperm determination.

How do I identify the male and female contributor when the male contributor is not vasectomized or I am not sure if he has a vasectomy (panties, feminine pad, oral sex stain, or a condom)?

You would order a differential lysis which will provide a separate PowerPlex profile on the male and female if the male is present by sperm cells and the female is present by epithelia  or buccal cells.  A differential lysis consists of 2 separate tests. It is possible that there is heavy contamination by the male presence (such as buccal cells from oral sex) and the extractions produce a combined profile consisting of more than one contributor. It is possible that the sperm cells have lysed (dissolution or destruction) and both the male and female fractions of the extraction may be similar or identical. Even when the profiles are mixed the results can be helpful in proving that a specific contributor is included or excluded from the stain.

How do I identify the male and female contributor when the male contributor is vasectomized  (panties, feminine pad, oral sex stain, or a condom)?

You would order a PowerPlex profile from a semen stain.  You will most likely obtain a mixed profile of more than one contributor. Even when the profiles are mixed the results can be helpful in proving that a specific contributor is included or excluded from the stain.

Why didn’t my DNA extraction produce a male profile when I was 100% positive that semen was present?

DNA is found in sperm, not semen. If an individual is vasectomized or azoospermic (producing no sperm), DNA will only be available from the epithelia cells shed during ejaculation. The success rate of DNA extraction of a vasectomized or azoospermic individual is greatly reduced but still possible.  The most sensitive extraction and profiling is by YPLEX. The sample was badly degraded which is normally caused by bacteria attacking the cells which inhibit the binding of the primers during the PCR amplification process.  Storing a moist sample in a Ziploc bag is the number one cause of this type of failure.  If you see mold or mildew on a sample you should expect it not to work. It is possible that the adulterer is vasectomized and you may want to consider other methods of catching the cheaters by hiring an infidelity Private Investigator.

What will my test results look like?

Please see the actual test examples section of our website.

How do I order?

Order online or by phone at 888-875-7574

What if the questions I have sound stupid or I’m not sure what to ask?

There is no such thing as a stupid question when you are needing assistance.  We are here to get the answers you need to move forward with your life. We do receive questions that are funny but you will receive a respectful reply.

How is your Home PSA Test Performed?


  • Cut the article in the area containing the suspected semen samples using the cutting tool.  The suspected substance can also be scraped from the article.

  • Place in the provided micro-tube and cover the cuttings and/or substance with the dissolution material.


  • Swab the stained area with the provided swabs and chemicals and place in the micro-tubes

Completion of test for destructive or non-destructive method

  • Add provided chemical to the micro-tube and mix.

  • Apply sample to PSA test cartridge.

  • Read results in 10 minutes or less.

If you have any further questions, please contact us or call us at 888-875-7574.