Derks–Smeets IAP, et al. – This article was written with the objective to figure out if BRCA1/2 mutation carriers produce fewer mature oocytes after ovarian stimulation for in vitro fertilization (IVF) with preimplantation genetic diagnosis (PGD), in comparison to a PGD control group. Ovarian response to stimulation expressed as the number of mature oocytes was decreased in BRCA1 but not in BRCA2 mutation carriers. Although oocyte yield was in correspondence with a normal response in all subgroups, this finding points to a possible negative impact of the BRCA1 gene on ovarian reserve. an save.