Hi & Welcome. Since there s an increased incidence of human fetal malformations or irreversible damage, Albendazole is contraindicated during pregnancy & for 1 month prior to conception. So, before taking this medication, a negative pregnancy test should be obtained or therapy should be started during the first week of menstruation. Effective contraception is recommended during therapy & for 1 month after the last dose. Since you had unprotected sex during your most fertile period there s a strong possibility of pregnancy. If you become pregnant while taking this drug or used during pregnancy inadvertently, it should be discontinued immediately and consult your gynecologist for periodic checkup including pelvic ultrasound to detect any such malformations in the growing fetus. Iron and folic acid tablets should taken and continued throughout the pregnancy.