Observational Study to Develop Dosing Chart

Inclusion Criteria: * Female aged of 19 to 39 years * Mean menstrual cycle in 25 to 35 days * Patients to whom Follitrope PFS will be administered in those scheduled to undergo the IVF-ET according to the GnRH agonist or antagonist protocol * In the past continuous IVF cycle failure less than 2 times Exclusion Criteria: * Patients having a history of ovarian, breast, uterus, hyperthalamus, or pituitary tumor * Abnormal uterine bleeding of undetermined origin * Prior hypersensitivity to a component of recombinant FSH * Ovarian cyst or enlargement of undetermined origin * Clinically significant endocrine abnormalities * Patients having polycystic ovary syndrome (PCOS) history * Poor Ovarian responder (Bologna criteria) * Patients who received Clomiphene citrate, Letrozole (Pemara), or Gonadotropin within 30 days prior to enrollment in this study