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Dr. Monica
Dr. Monica, Board Certified Physician
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Experience:  Experienced U.S. Primary Care Physician treating children, adults, pregnant women, and the elderly.
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What the chances of contracting an std from 1 single sex act

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What the chances of contracting an std from 1 single sex act if you are a male and used a condom with vaginal intercourse but not for oral? oral was very short and so was the intercourse. Im freaking out.

Hello and welcome to justanswer!

Do you have any other medical condition ?

What about your partner's sexual health , if you know that ?

Customer: replied 7 years ago.
I dont have any other medical condition. Im not sure about my partners medical history.

Thank you very much for your input.

If one uses latex or polyurethane condom , the chances of HIV transmission is nil because , such a material totally blocks the transmission of viruses.Regarding , oral sex, the person giving the "blow job' i.e. the receiver has more chances of acquiring HIV , especially from the preejaculate (cum) and if she/he has oral sores , cuts in the mouth etc.For the person who is doing the insertive job has minimal HIV transmission from merely saliva but can acquire HIV if she/he has blood in the mouth etc.The same is true if he has cuts , sores on the penis which come in contact with bleeding gums etc.

Other STD's like gonorrhea, chlamydia, and non-gonococcal urethritis (NGU). These usually can be treated easily with antibiotics. You may also get syphilis (which usually can be treated easily with antibiotics (if identified early enough) and herpes which can be cured by using antibiotics.The same is true for HPV .However if dental dams or condoms are used for oral sex , the chances of transmission are negligible.If you feel uncomfortable , can get screened out for STD's during a week's time when when the results might be positive if at all they are there.The sooner the STD's are caught the more the chances they will be treated.

Hope i have answered your question.

Customer: replied 7 years ago.
I understand that its possible, but how possible? What are the chances in percentage that such a transmission could occour. Should i be worried? Is it common for that to take place especially orally? how likely is it if i am a man to contract an std from a woman one act of oral sex? does it happen every time? 50/50 1%? etc......about the hiv, how minimal is minimal?

Thank you very much for your inquiry.

Actually , the estimation of risk of transmission through oral route is relative to anal and vaginal sex.Therefore , it is based upon two types 1.theoretical 2.documented.Theoretical means it is possible and documented means if any event has been recoreded with such an occurrence.Actually the oral cavity and the mucous membrane of the mouth are very resistant to viruses including HIV and HIV cant be transmitted either way to the ACTIVE or Receptive partner unless there is cut, abrasion etc. in the mouth or on the penis.During different studies it is estimated that transmission of HIV on either side is less than 2.8% through oral route.This means that the chances of getting such infection is negligible, though possible through oral route.It is not about the frequency , but rather on the viral load , abrasions and cuts on either side which decides the transmission.For you i will suggest to screen yourself out after 10 days for HIV , to remove your suspicion.Generally women ( receptive ) are more prone to contact HIV than men( active)Good luck.

Hello, I'm sorry but I disagree with the expert's answer. It is incorrect advice to tell a person to get an HIV test within 10 days of exposure. Most people will take 2-8 weeks to develop antibodies against HIV, although some people will take up to 3 months to develop antibodies. The antibodies of HIV are what is tested for in an HIV screening test. For this reason, it is recommended that a person get an HIV test 3 months after the potential exposure.

Customer: replied 7 years ago.
yeah but how likely is it if the sex was protected except for the oral .....could you please give me the same information (in terms of percentage chance) on others std's that can be contracted through recieving oral sex from a woman, as well as sex with a condom?
There are various studies to try to quantify the risk percentage which can be very difficult for various reasons. However, using your example, let's say your partner definitely has HIV. Let's assume that she has a very high viral load (meaning that she has a lot of HIV in her bloodstream, but usually this would mean that she would also be very ill.) Even in that situation, if the condom did not break or fall off, you have less than a 10% chance of contracting HIV from her. This is assuming there was no blood to blood transmission as well.

Now, the more likely scenario is that she doesn't have HIV, but I suppose we cannot assume that. So if she does have HIV, let's assume her viral count is low. This would bring your risk down to closer to 1-5% percent. Obviously, if she does not have HIV, your chances of getting it from her are 0%. Chances of getting other STDs while using a condom are less than 1% in most cases, unless there was significant contact or foreplay without the condom.

You have a less than 5% chance (and likely closer to 1% or less) of contacting something from intercourse while using a condom. The exception would be herpes if she had active lesions on an area that rubbed your unprotected skin.

As far as STDs and oral sex, you have a very slim chance of contracting STDs such as Chlamydia, HPV, or HIV. Gonorrhea and syphilis is a little more common to get from oral sex, but it is usually only if you had sores or open wounds on your penis. From her performing oral sex on you, in most cases considering most STDs, it is likely less than 1% of transmission. Your chances are higher when it comes to Herpes, because if she had active lesions in the oral area, you are at risk of herpes infection, possibly 50% or more IF she had active disease (active lesions), slightly less (5-25%) if she had no active lesions but has herpes).

Hope that helps. Please try not to worry too much as your chances for getting anything are relatively low, even if she had one or more of these STDs.
Customer: replied 7 years ago.
in the beginning of the third paragraph, could you define "very slim"? Also does the same hold true for any chance of pregnancy?
Absolutely, you are correct. Chances of pregnancy are also likely less than 1-2% in your case. Studies have shown that 1-2 women per year will become pregnant even if they used condoms correctly and consistently. So your chances in this one given instance of not getting pregnant are the same or better.

Very slim meaning less than 1% in most cases.
Customer: replied 7 years ago.
you rock! Thanks!!
You are welcome. Thanks for using Just Answer.
Dr. Monica, Board Certified Physician
Category: Medical
Satisfied Customers: 816
Experience: Experienced U.S. Primary Care Physician treating children, adults, pregnant women, and the elderly.
Dr. Monica and 5 other Medical Specialists are ready to help you
Hello- just thought I'd update the answer with some new info. Another expert was kind enough to assist me by providing a link that shows that your chances are actually much much less. I had been referencing other studies that were much less specific. Although I did not read this study directly that is used to come up with this data, the CDC uses it in an article and sites that your chance of getting HIV (without a condom) during one episode of receiving oral sex is less than 1 in 10,000. In other words, you have a .0001% of getting HIV from her giving you oral sex that one time. So it would be extremely rare and almost unheard of. Here is the link in case you are interested:

Hope this just reassures you more! Thanks again.
Customer: replied 7 years ago.

In terms of pregnancy, I know you said a 1-2% chance....Does a spermacidal comdom reduce this? Is age a factor? She is 39. Can a woman be pregnant and still get her period?

Its probably less than a 1% chance based on one sexual encounter, even less likely considering her age, and even less likely if spermicde is involved. And no, unless the "period" was extremely light and not a true period, then she cannot be pregnant and still have a normal flow period.
Dr. Monica, Board Certified Physician
Category: Medical
Satisfied Customers: 816
Experience: Experienced U.S. Primary Care Physician treating children, adults, pregnant women, and the elderly.
Dr. Monica and 5 other Medical Specialists are ready to help you
Customer: replied 7 years ago.

Ok. Please help. I am now in full freakout. I have been closely examining myself recently and I noticed some extremely tiny, almost microscopic bumps just under the head of my penis on one side and a few on the shaft. They feel like the tiniest grain of sand and are almost invisible. The same color of my skin or slightly lighter. Could this be a sign of an STD???? Im ready to jump off a cliff............

Customer: replied 7 years ago.
Also, how long do I need to wait before I can get tested? I need to go ASAP. Ive been doing some research on and it shows much higher rates of infection among african americans. We are both caucasion. Does this play a role? How common are these types of things? I know i was clean prior to this encounter because I always get tested. I read chlamidia and ghonnorea (sp?) can be in a persons throat. How common is that??? Would'nt that person be ill? What is the deal? So frustrating......this is crazy.I cant even sleep. this is the most terrible thing ive ever experienced in my life. How can I be 100% sure that im not infected? Im ready to lose it.
I will try to help.Do you have a specific question?
Hello again...

First of all, try not to worry. I can't tell you how many times I have patients worried about small bumps that they happen to notice after a worrisome exposore or sexual encounter and it turns out to be nothing. Small bumps on the penis like you are describing are often called "milia" and are benign and normal. They do not indicate an STD at all. They can come and go and sometimes people will notice them more after lots of friction or rubbing. It would be extrememly unlikely for these to be the beginning of warts or HPV. However, if they get bigger or start to look like warts, that is a possibility and you should get checked to make sure. Based on what you are describing, however, I think the more likely thing is that these are milia, so they will just stay that way or eventually go away, and it is not a disease or anything transmitted sexually.

You should still wait about 3 months before checking for HIV or Syphilis or Hep B, especially if you had a recent negative exam you don't need one sooner. To get checked for Gonorrhea or Chlamydia you can get checked 1-3 weeks. If you are super worried you can get checked in 1 week, then again 4 weeks later. If you are negative both times, then you don't have those STDs. Pretty uncommon for either of those to be in a person's throat, although the risk is slightly higher for Gonorrhea. It is still extremely unlikely that you got anything from her throat, and the recommendations about getting checked are the same: 1 and 4 weeks.

The fact that you are both caucasian doesn't change the fact that your risk of getting anything is really really low.

Please try not to worry so much! I really really think you are getting too stressed about this. Think about worst case scenario- if you got an STD however unlikely that would have been, then it was probably something common like Chlamydia. I think you have way less than a 1 % chance of getting this, but lets say you did. You may not even get symptoms, but if you test positive then you will get antibiotics (that you take that same day, only once) and then THAT'S IT! You are cured. You need to not have sex for 7 days after the antibiotics. I am not even going to give an example regarding the chances you got HIV because if you got it with only a .0001% risk of getting it, then you should play the lottery because those would be really crazy odds! So please- try to calm yourself down. Remember:

  1. You probably didn't get anything
  2. If you did it is most likely an easily curable STD
  3. But you still probably didn't get anything

Try to do some breathing exercises, stay active to get out all of your worries, and get checked in 1 week, 4 weeks, and again in 3 months (just for the blood tests then).

Let me know if you have questions. Bu try not to worry

Dr. Monica