Objective: To compare the clinical outcomes of follicular versus luteal phase ovarian stimulation in women with poor ovarian response (Bologna criteria) undergoing IVF.
Methods: This retrospective study investigated 446 patients submitted to 507 cycles in three groups. First, the two larger cohorts were examined: 154 patients treated with luteal phase ovarian stimulation (Group Lu); and 231 patients administered follicular phase ovarian stimulation (Group Fo). Then the clinical outcomes of 61 patients submitted to double ovarian stimulation were analyzed. Clinical outcomes included number of retrieved oocytes, fertilization rate, cleavage rate, top-quality embryo rate, clinical pregnancy rate (CPR), and live birth rate (LBR).
Results: Longer stimulation, higher dosages of HMG, and higher MII oocyte rates were achieved in Group Lu (p<0.001). There were no significant differences in CPR and LBR between the two groups offered frozen-thawed embryo transfer (28.4% vs. 33.0%, p=0.484; 22.9% vs. 25.5%, p=0.666). In the double ovarian stimulation group, the number of oocytes retrieved in the luteal phase stimulation protocol was higher (p=0.035), although luteal phase stimulation yielded a lower rate of MII oocytes (p=0.031). CPR and LBR were not statistically different (13.8% vs. 21.4%, p=0.525; 10.3% vs. 14.3%, p=0.706).
Conclusion: Luteal phase ovarian stimulation may be a promising protocol to treat women with POR, particularly for patients unable to yield enough viable embryos through follicular phase ovarian stimulation or other protocols.
Keywords: IVF-ET; Poor ovarian response; live birth rate; ovarian stimulation.