In order for there to be any risk of pregnancy, you need both sperm and an egg. You didn’t mention if you’re on birth control or not. If you’re on the birth control pill, patch, shot, or vaginal ring and are using it as directed by your doctor, then you likely wouldn’t even be ovulating. That’s how most hormonal birth control pill works – pretty interesting, eh? Other effective methods of birth control include the IUD and implant. If you’re not using birth control, however, then you may indeed have an egg available for fertilization in which case we start wondering whether sperm were available.
Readers who have been through a quality sex education course may know that sperm are made in the testes. They mature in the epididymis (which are spiraly parts above the testes) and, when a man ejaculates, the sperm join the rest of the seminal fluids to form and make their way out of the body. Sperm first have to travel through the vas deferens and then they mix with fluid from the prostate gland, Cowper’s glands (which make pre-ejaculatory fluids, or pre-cum), and seminal vesicles and leave the body as semen.
It Takes a Fluid
If “this guy” you were with was aroused and erect but didn’t have ay fluids coming from his penis, then although he has sperm inside his body, it sounds like they stayed inside his body – or at least they did until he got home and masturbated or you two moved on to other kinds of sex. So even if you are not on birth control (and there was an egg), if there was no sperm getting near your vaginal opening, then there’s no chance of pregnancy. Plus, you both had on underwear! Sperm aren’t getting through his boxers and your thong, anyway.
Look Into Birth Control
If you’re not ready to become pregnant, but are likely to find yourself being sexual in penis-vagina ways again soon, please consider talking with a doctor or nurse about birth control. There are so many great options available to you that are effective and affordable – and possibly even free. And if you’re concerned about sexually transmitted infections (STI) then consider using condoms and/or steering clear of even dry humping until you know more about a partner’s STI status. STIs that are transmitted through genital skin contact (like HPV genital warts and herpes) can pass from one person to another this way.
To learn a great deal more about sex (pregnancy risk, STIs, but also things like pleasure and orgasm), check out sex Q&A books like Sex Made Easy or Sexpertise, each written by faculty who teach human sexuality classes.