Hi Doctor, I'm 24 Yrs Old And Have Just Been

Hi doctor, I'm 24 yrs old and have just been prescribed Itraconazole 100mg capsules for a 3 week (2ice a day) course. I was not able to tell my dermatologist at the time, but I am also using birth control pills (Loestrin 20). Do these drugs have any serious interactions? Also, does this combination increase my chances of pregnancy? If yes, how long after I stop the Itraconazole will the Loestrin be fully effective again?
Thank you!