Endometrial scratching in luteal phase of a spontaneous menstrual cycle may increase pregnancy rate in women with unexplained infertility.

Inclusion Criteria:

• women aged between 20 and 39 years with at least one year of infertility
• regular menstruation with the length of the cycle between 22-34 days and ovulation confirmed by appropriately timed mid-luteal progesterone
• fertile semen variables
• bilateral tubal patency (demonstrated by laparoscopy or hysterosalpingography).