{Reference Type}: Case Reports {Title}: Unexpected repeat immature oocyte response after IVF stimulation: a case report. {Author}: Mishra V;Chirumamilla L; {Journal}: Gynecol Endocrinol {Volume}: 34 {Issue}: 2 {Year}: Feb 2018 {Factor}: 2.277 {DOI}: 10.1080/09513590.2017.1369514 {Abstract}: The purpose of ovarian stimulation in IVF is to recover mature oocytes at metaphase II stage which are capable of fertilization either when mixed with sperm or after ICSI. However, there have been instances when even after controlled ovarian stimulation (COS) and correct administration of human chorionic gonadotrophin (hCG) trigger for final oocyte maturation, the oocytes were found to be arrested at germinal vesicle (GV) or metaphase I (MI) stage. Similar dilemma is faced in cases of empty follicle syndrome (either genuine or due to inadequate response), however, in this condition, there is no retrieval of oocytes despite presence of mature looking follicles. We present an interesting case where despite presence of normally growing follicles and documentation of correct response to trigger and rise in estradiol levels, two subsequent IVF cycles; one triggered with recombinant hCG and second with GnRH agonist, hCG failed to yield mature oocytes. Both cycles yielded expected number of oocytes but all at immature MI stage even after dual trigger.