Prostaglandin E1 can be inserted in a pellet (suppository) form into the urethra to attain erections. This technique also is not popular because of occasional side effects of pain in the penis and sometimes in the testicles, mild urethral bleeding, dizziness, and vaginal itching in the sex partner. Men also need to remain standing after inserting the pellet in order to increase blood flow to the penis, and it may take 15-30 minutes to attain an erection. Prostaglandin can cause uterine contractions and should not be used by men having intercourse with pregnant women unless condoms or other barrier devices are used.