Predicting the FSH threshold dose in women with WHO Group II anovulatory infertility failing to ovulate or conceive on clomiphene citrate.
BACKGROUND The objective of this investigation was to establish independent predictors of follicle-stimulating hormone (FSH) threshold dose in anovulatory women undergoing ovulation induction with FSH preparations.


METHODS
One hundred and fifty-one patients with WHO Group II anovulatory infertility failing to ovulate or conceive on clomiphene citrate underwent ovarian stimulation with FSH-only preparations following a low-dose step-up protocol. The individual FSH threshold dose was defined as the FSH dose when meeting the human chorionic gonadotrophin criteria (one follicle > or =17 mm, or 2-3 follicles > or =15 mm). The influence of demographics, physical characteristics, obstetric and infertility and menstrual cycle history, ovarian ultrasonography, endocrine parameters and type of gonadotrophin preparation on the FSH threshold dose was assessed through multiple regression analysis.


RESULTS
In the univariate analysis, age, body mass index (BMI), failure to ovulate with clomiphene citrate, menstrual cycle history (amenorrhea, oligomenorrhea or anovulatory cycles of 21-35 days), mean ovarian volume, LH/FSH ratio, testosterone and free androgen index were significant (P < 0.05) predictors of FSH threshold dose. In the multivariate analysis, menstrual cycle history, mean ovarian volume and BMI remained significant (P < 0.001).


CONCLUSIONS
The individual FSH threshold dose for ovulation induction in anovulatory women can be predicted based on three variables easily determined in clinical practice: menstrual cycle history, mean ovarian volume and BMI. A FSH dosage nomogram was constructed based on these parameters.
Nyboe Andersen
Anders
A
Fertility Clinic, Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, 2100 Copenhagen, Denmark. anyboea@rh.dk
Balen
Adam
A
Platteau
Peter
P
Devroey
Paul
P
Helmgaard
Lisbeth
L
Arce
Joan-Carles
JC
D000328:Adult; D015992:Body Mass Index; D002996:Clomiphene / Q000627:therapeutic use; D005260:Female; D005300:Fertility Agents, Female / Q000627:therapeutic use; D005640:Follicle Stimulating Hormone / Q000008:administration & dosage*; D005544:Forecasting; D006728:Hormones / Q000008:administration & dosage*; D006801:Humans; D007247:Infertility, Female / Q000188:drug therapy*; D009929:Organ Size; D010053:Ovary / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D010060:Ovulation / Q000187:drug effects; D010062:Ovulation Induction; D012720:Severity of Illness Index; D016896:Treatment Outcome; D014463:Ultrasonography
D005300:Fertility Agents, Female; D006728:Hormones; D002996:Clomiphene; D005640:Follicle Stimulating Hormone