To Investigate the Cumulative Live Birth Rates Using GnRH Antagonist or Agonist Protocol for COS in ART Treatment

Inclusion Criteria:

• Infertile women planning to undergo IVF/ICSI cycle using conventional GnRH agonistlong protocol or GnRH antagonist protocol

• Age ≤ 38 years old

• Basal AFC 8~20

• Basal FSH≤10 IU/L

• Basal E 2 <200pmol/L

• Normal uterus and at least one side of the normal ovary

• Informed consent form signed

• Willing to follow the study protocol, and able to complete this study

Exclusion Criteria:

• Previous IVF/ICSI cycles >2

• Severe hydro-salpinx (Ultrasound shows hydro salpinx﹥2cm)

• Severe endometriosis (Grade III - IV)

• Polycystic ovarian syndrome (PCOS)

• History of recurrent miscarriages (>2 times of miscarriages)

• Plan to undergo ovarian stimulation for preimplantation genetic diagnosis orpreimplantation genetic screening, oocyte donation, and social or medical freezing ofoocytes

• Any major systemic disease that as per Investigator's discretion precludes subject forparticipation in the study

• With pregnancy contraindications

• Alcoholism, drug abuse, drug addiction or patients with uncured sexually transmitteddisease

• According to the judgment of the Investigator, any medical condition or anyconcomitant surgery/medications that would interfere with evaluation of studymedications

• Simultaneous participation in another clinical study

• Plan to use urinary gonadotrophin during COS treatment