Table 1 Available randomized trials regarding the use of letrozole during the follicular phase in IVF/ICSI cycles
Pituitary downregulation protocol/groups | Ovarian stimulation | Patients (N) | Clinical pregnancy rate (%) | Implantation rate (%) | Fertilization rate (%) | No oocytes (mean) | Total FSH dose (mean) | |
|---|---|---|---|---|---|---|---|---|
Normoresponders | ||||||||
Verpoest 2006 [9] | Antagonist | rFSH+letrozole | 10 | 50 | 31.25 | 63.3 | 13.8 | 1575 |
Antagonist | rFSH | 10 | 20 | 12.5 | 77.4 | 9.6 | 1650 | |
Poor responders | ||||||||
Goswami 2004 [10] | - | rFSH+letrozole | 13 | 23 | NA | NA | 1.6 | 150 |
Agonist | rFSH | 25 | 24 | NA | NA | 2.1 | 2865 | |
Garcia-Velasco 2005 [4] | Antagonist | rFSH+ HMG+ letrozole | 71 | 22.4 | 25 | 68.2 | 6.1 | 3627 |
Antagonist | rFSH+ HMG | 76 | 15.2 | 9.4 | 63.3 | 4.3 | 3804 | |
Ozmen 2009 [11] | Antagonist | rFSH+letrozole | 35 | 28.6 | NA | 92.4 | 4.9 | 2980 |
Antagonist | rFSH | 35 | 17.1 | NA | 97.2 | 4.8 | 3850 | |
Davar 2010 [12] | Antagonist | rFSH/HMG + letrozole | 45 | 4.4 | 3.8 | 67.3 | 2.8 | 3158 |
Agonist | rFSH or HMG | 49 | 12.3 | 7.7 | 70.7 | 4.4 | 3458 |