Hello Welcome to healthcaremagic I have gone through your query & appreciate your concern Yes pregnancy is possible through unprotected intercourse. Unprotected sexual intercourse is the normal way by which women get pregnant. Missing your period is normally first symptom of getting pregnant. So you might be pregnant. You should do a urine pregnancy test with a fresh early morning urine sample. You can go for the assessment of the serum beta-hCG titres for an earlier and better confirmation. If positive, you are pregnant and nothing can be done to prevent the pregnancy since it has happened already. As it seems that you doesn t want to continue pregnancy, please consult a gynecologist for proper evaluation, get a trans-vaginal sonogram to locate the sac and the age of the pregnancy and proceed for an induced medical abortion under surveillance. Hope this information helps.