TY - JOUR
T1 - Understanding ovarian hypo-response to exogenous gonadotropin in ovarian stimulation and its new proposed marker-the follicle-to-oocyte (FOI) index
AU - Alviggi, Carlo
AU - Conforti, Alessandro
AU - Esteves, Sandro C.
AU - Vallone, Roberta
AU - Venturella, Roberta
AU - Staiano, Sonia
AU - Castaldo, Emanuele
AU - Andersen, Claus Yding
AU - De Placido, Giuseppe
PY - 2018
Y1 - 2018
N2 - Hypo-responsiveness to controlled ovarian stimulation is an undervalued topic in reproductive medicine. This phenomenon manifests as a low follicles output rate (FORT) with a discrepancy between the relatively low number of pre-ovulatory follicles which develop following ovarian stimulation as compared to the number of antral follicles available at the start of stimulation. The pathophysiology mechanisms explaining the ovarian resistance to gonadotropin stimulation are not fully understood, but the fact that both hypo-responders and normal responders share similar phenotypic characteristics suggests a genotype-based mechanism. Indeed, existing evidence supports the association between specific gonadotropin and their receptor polymorphisms and ovarian hypo-response. Apart from genotypic trait, environmental contaminants and oxidative stress might also be involved in the hypo-response pathogenesis. The ratio between the number of oocytes collected at the ovum pick up and the number of antral follicles at the beginning of OS [Follicle to oocyte index (FOI)] is proposed as a novel parameter to assess the hypo-response. Compared with traditional ovarian reserve markers, FOI might reflect most optimally the dynamic nature of follicular growth in response to exogenous gonadotropin. In this review, we contextualize the role of FOI as a parameter to identify this condition, discuss the underlying mechanisms potentially implicated in the pathogenesis of hyporesponse, and appraise possible the treatment strategies to overcome hyper-responsiveness to gonadotropin stimulation.
AB - Hypo-responsiveness to controlled ovarian stimulation is an undervalued topic in reproductive medicine. This phenomenon manifests as a low follicles output rate (FORT) with a discrepancy between the relatively low number of pre-ovulatory follicles which develop following ovarian stimulation as compared to the number of antral follicles available at the start of stimulation. The pathophysiology mechanisms explaining the ovarian resistance to gonadotropin stimulation are not fully understood, but the fact that both hypo-responders and normal responders share similar phenotypic characteristics suggests a genotype-based mechanism. Indeed, existing evidence supports the association between specific gonadotropin and their receptor polymorphisms and ovarian hypo-response. Apart from genotypic trait, environmental contaminants and oxidative stress might also be involved in the hypo-response pathogenesis. The ratio between the number of oocytes collected at the ovum pick up and the number of antral follicles at the beginning of OS [Follicle to oocyte index (FOI)] is proposed as a novel parameter to assess the hypo-response. Compared with traditional ovarian reserve markers, FOI might reflect most optimally the dynamic nature of follicular growth in response to exogenous gonadotropin. In this review, we contextualize the role of FOI as a parameter to identify this condition, discuss the underlying mechanisms potentially implicated in the pathogenesis of hyporesponse, and appraise possible the treatment strategies to overcome hyper-responsiveness to gonadotropin stimulation.
KW - Assisted reproductive technology
KW - Follicle output rate
KW - Follicle to oocyte index
KW - Hypo-response
KW - In vitro fertilization
KW - Ovarian stimulation
KW - Ovulation induction
KW - POSEIDON criteria
U2 - 10.3389/fendo.2018.00589
DO - 10.3389/fendo.2018.00589
M3 - Review
C2 - 30386293
AN - SCOPUS:85055145546
SN - 1664-2392
VL - 9
SP - 1
EP - 7
JO - Frontiers in Endocrinology
JF - Frontiers in Endocrinology
IS - OCT
M1 - 589
ER -