Can someone become asexual after being sexually active?

This is going to get complicated:

I'm asexual, I've had sex. In fact, it probably won't be the last time I have sex either. I have little interest in it like most people, and I do not experience "sexual attraction". However I person doesn't suddenly stop having an interest in sex when they used to be, and they don't just stop becoming sexually attracted if they used to be, That, would require more of a medical check up and possibly a medical/hormonal issue. If you were sexually attracted and had absolutely no issue with sex before and you've now become uninterested - you would not be asexual, no. That would be a problem that you need to investigate into.

There's multiple types of asexuals, and it's a very very large spectrum. From Demi/Grey-sexuals, to Asexuals who are also aromantic. (Aromantic meaning no romantic attraction.) You have asexuals that just don't experience sexual attraction, but don't really find sex "disgusting", and then you have asexuals that are "sex repulsed". However that has been who they are since childhood, and perhaps even birth. It's thought that sexual attraction does not develop until toward the pre-teen ages, and asexuals are thought to have "skipped" over that part of their sexual development. There's nothing wrong with them, it's not a disease or anything, their brain just doesn't really care for sexual attraction or sex.

Me, I am an asexual who doesn't mind the talk of sex on occasion, I can even make sex jokes. But at times, I can't discuss the act of sex, or handle it in a film. I very very rarely experience sexual attraction at all, and when I do, it's under very very strict and specific circumstances. I will look a male (as I'm a straight female...not all asexuals are) and think "Aww, he's handsome, good for him." and others will be saying "you're hot and yummy! Txt me!" I'll double take and realize "I was supposed to think he was yummy?" *shrug*

Asexuals mostly just don't look at a person and think "Oh my God s/he's hot, let me do him/her right now!" We're more like "Hey, he/she seems nice, I wonder if he/she has a blog full of his/her favorite fandoms." We don't even think of dating for a long long time into the friendship or knowing said person.

So again, can an asexual be an asexual if they've been sexually active? Yes, because being active doesn't mean that they were experiencing sexual attraction or But they won't BECOME asexual after being sexually active. A lesbian can have sex with a male and realize later she's a lesbian...but she has always been a lesbian. She won't BECOME a lesbian just because she "switched" to females. Sexuality is fluid, but it doesn't have a switch to turn it on or off. It just has switches labelled "turn on" or "turn off" Asexuals are "turned off" a lot more than they're on, and most really don't mind it staying in the "off" setting.

No. You can choose to be CELIBATE, which is where one abstains from sex. Asexuals experience no sexual attraction, and have always felt that way. Think of asexuality as the opposite of bisexuality (whereas bi folks are attracted to both men and women, asexuals are attracted to neither). Crude comparison, but you get the idea.

If you experience a sudden loss of interest in sex, then it may be due to stress, depression, or medical issues. Please don't confuse sexual dysfunction with asexuality.

Yes, they can choose to be A-sexual.