To evaluate the overall performance and oocyte quality of follicular phase stimulation (FPS) vs. luteal phase stimulation (LPS) among patients undergoing double ovarian stimulation (DuoStim). Observational retrospective two-center cohort study including 79 infertile women who underwent a total of 87 DuoStim cycles between January 2017 and May 2019. Besides assessing baseline characteristics in order to determine the patients' clinical profile, we analyzed the FPS and LPS regarding the total dose of gonadotropin received, the duration of stimulation, the number and maturity of oocytes, fertilization and blastocyst formation rates, and the number of blastocysts obtained. The patients' baseline characteristics were compatible with a diminished ovarian reserve and poor reproductive prognosis. While the luteal phase needed longer stimulation (12 days (5-19) vs. 11 (7-16), p < .001) and slightly higher gonadotropin doses (2946 ± 890 IU vs. 2550 ± 970 IU, p < .001), no significant differences were detected in the oocyte maturity, fertilization, and blastocyst formation rates. However, the number of oocytes retrieved (5 (0-16) vs. 4 (0-15), p = .006), mature oocytes (4 (0-15) vs. 3 (0-11), p = .032), and blastocysts obtained (70 vs. 53) were substantially greater after LPS. The DuoStim strategy in poor prognosis patients increases the number of oocytes and blastocysts available. Moreover, the number of oocytes and blastocysts obtained are higher after LPS when compared to FPS. Thus, it should be considered for selected patients in order to not only improve reproductive outcomes but also shorten the time to pregnancy.