Objective: To study whether the unexpected poor ovarian responders optimization of uterine receptivity with a flexible controlled ovarian hyper stimulation protocol based on the Biophysical Profile of the Uterus, has an impact on their reproductive performance. Design: Observational Prospective study. Setting(s): i) General hospital-IVF and Infertility Centre; ii) University hospital. Patient(s): 44 normogonadotrophic young women (26 - 38 yrs) with previous “unexpected” poor ovarian response underwent IVF/ICSI treatment on a protocol based on the Biophysical Profile of their uterus (Group A). The same patients were used as controls in a preceded IVF cycle on the conventional stimulation protocol. Intervention(s): None. Main outcome measure(s): Pregnancy, miscarriage and home take baby rates, amount and duration of gonadotropins required, number and quality of embryos resulted, Biophysical Profile of the Uterus score. Result(s). Treatment in Group A in comparison to Group B resulted in significantly larger number of eggs retrieved per patient, and improved fertilization rates and higher number of embryos/ET (p = 0.011, 0.010 and 0.034 respectively). Group A also demonstrated a trend for higher rates of clinical pregnancy (29.5% v.s. 15.9%), viable stage pregnancies ≥ 24 weeks (33.3% v.s. 20%) and home take babies (26.6% v.s. 16%). The amount of gonadotropins used per patient (IU) was similar in the two groups (p = 0.264). Cancellation, implantation and miscarriage rates as well as embryos quality, although superior in the treatment Group A, showed no significant difference. The number of pregnancies achieved in Group A, were directly related with the score in the Biophysical Profile of the Uterus 12 point scale. Conclusion(s): Unexpected Poor Ovarian Responders on the flexible IVF/ICSI protocol (Group A), adjusting the management according to the Biophysical Profile of their uterus (duration of stimulation, day of HCG and day of embryo transfer), had a significantly better performance in comparison to the Group B managed on the conventional protocol in this difficult to manage and so far, rather understudied population.