To analyse the impact on cycle outcome of LH supplementation in ovarian stimulation controlled with a GnRH antagonist in two ages groups: patients upto 35 years old, and patients aged between 36 and 39 years old.

All patients received an oral contraceptive pill with 0.030 mg of ethinyl-estradiol and 3.0 mg of drospirenone the cycle prior to ovarian stimulation. On the second day of menstruation, patients started ovarian stimulation as follows:

Patients < 36: 225 IU/day of recombinant FSH (FSH alone group) or 150 IU of rFSH and 75 IU of rLH/day (FSH+LH group) for 5 days. On day 6, a 0.25 mg/day dose of the GnRH antagonist Cetrorelix is added until the day of rCG administration.

Patients 36-39: Initial dose of 300 IU of rFSH /day (FSH alone group)) or 225 IU of rFSH and 75 IU of rLH/day (FSH + LH group) for 5 days. On day 6, a 0.25 mg/day dose of the GnRH antagonist Cetrorelix is added until the day of rCG administration.

A maximum of 3 embryos were transferred on day 3 of embryo development.

Inclusion Criteria:

• 1st-2nd IVF cycle.
• Age until 39 years old
• BMI: 18-29.9.
• Basal FSH < 12 IU/L

Exclusion Criteria:

• LH:FSH > 2 (PCO)
• Low response background (< 5 oocytes)
• Endometrioma
• Recurrent pregnancy loss
• Any preimplantational genetic diagnosis indication
• Any systemic, metabolic or endocrinological disorder.