***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: OBJECTIVE To assess whether ovarian volume of World Health Organization II anovulatory patients in the early follicular phase predicts the response to ovulation induction with gonadotropins . DESIGN Retrospective data analysis of two prospect i ve , r and omized , multicenter studies . SETTING Clinical development unit of biotechnology company . PATIENT(S ) Four hundred sixty-five World Health Organization II anovulatory patients undergoing ovulation induction .  MAIN OUTCOME MEASURE(S ) Ovarian response to stimulation , ovulation ( mid-luteal serum progesterone > 30 nmol/L ) , cancellation rate , pregnancy rate , and incidence of the ovarian hyperstimulation syndrome ( OHSS ) according to baseline ovarian volume ( day 2 - 5 ) before stimulation . RESULT ( S ) Mean ovarian volume was 11.55 + /- 6.0 cm(3 ) ( range , 0.8 - 49.3 cm(3 ) ) . Small ovarian volume was associated with lower rates of cycle cancellation owing to risk for OHSS ( 3 vs. 29 patients [ 2.8 % vs. 9 % ] ) . Patients with small ovarian volume ( < 7.25 cm(3 ) ) required fewer ampules of FSH ( 1373 IU vs. 1629 IU ) and shorter duration of stimulation ( 16 vs. 18.1 days ) and had higher ovulation rate than did patients with mid-range and larger ovarian volume ( 84.3 % vs. 69.1 % and 68.8 % , respectively ) . The clinical pregnancy rate per cycle of hCG administration was similar in the three groups ( 25.8 % , 28.1 % , and 27.5 % ) . CONCLUSIONS World Health Organization II anovulatory women with medium-sized or large ovaries who are undergoing low-dose gonadotropin stimulation for ovulation induction may have higher risk for OHSS than do women with small ovaries . Women with small ovaries who meet criteria for administration of hCG respond better to ovulation induction and have a similar likelihood of conceiving compared with women with larger ovaries We previously tested a combined regimen based on the administration of gonadotropin in the early follicular phase followed by pulsatile gonadotropin-releasing hormone ( GnRH ) until complete follicular maturation in patients suffering from polycystic ovarian disease . Despite good clinical results , a high rate of premature luteinization was observed with this approach . We therefore evaluated in this study whether starting pulsatile GnRH therapy before gonadotropin administration might reduce premature luteinization .  Eight women underwent induction of ovulation with both combined therapy and pure exogenous follicle-stimulating hormone alone using a crossover scheme . No premature luteinization and a single follicular growth were recorded with the modified combined regimen . Clinical results ( 8/8 versus 3/7 ovulatory cycles ; 3/8 versus 1/7 pregnancies ) favor the combined approach over gonadotropin alone A low dose step-up and step-down regimen for induction of ovulation using urinary FSH was compared in a prospect i ve r and omized fashion in 37 normogonadotropic clomiphene-resistant oligo- or amenorrheic infertile women . The objectives was to assess potential differences in duration of treatment , ovarian stimulation ( serum FSH levels ) , and response [ serum estradiol ( E2 ) levels and number and size of follicles ] . Monitoring  ( blood sampling and transvaginal sonography )  took place on the day of initiation of treatment , the first day of ovarian response as assessed by ultrasound ( i.e. the first day a follicle > or = 10 mm could be recognized ) , the day of hCG administration to induce ovulation , and 3 days thereafter . The median duration of treatment in the low dose step-up group was 18 ( range , 7 - 41 ) days compared to 9 ( range , 4 - 16 ) days in the step-down group ( P = 0.003 ) , and the total numbers of ampules administered were 20 ( range , 7 - 69 ) and 14 ( range , 7 - 33 ) , respectively ( P = NS ) . Serum FSH levels from the first day of sonographic ovarian response until the administration of hCG were constant ( median increase , 2%/day ) in patients receiving the low dose step-up protocol , but showed a decrease ( median , 5%/day ) in step-down cycles ( P < 0.001 ) . Monofollicular growth , defined as not more than one follicle 16 mm or larger on the day of hCG administration , was observed in 56 % of low dose step-up and 88 % of step-down cycles ( P = 0.04 ) . The percentage of patients with normal range periovulatory E2 serum levels ( 500 - 1500 pmol/L ) was 33 % in the low dose step-up group vs. 71 % in the step-down group ( P = 0.03 ) . We conclude that a step-down protocol for gonadotropin induction of ovulation exhibits a more physiological , late follicular phase FSH serum profile than a low dose step-up protocol . This results in a shorter duration of treatment , a greater number of monofollicular cycles , and more cycles with periovulatory E2 levels within the normal range in the step-down protocol BACKGROUND This study revisited the ultrasonographic diagnostic criteria of polycystic ovary syndrome ( PCOS ) and studied the relationship between the major hormonal and metabolic features of PCOS and the follicle number per ovary ( FNPO ) . METHODS This prospect i ve study included 214 women with PCOS compared with 112 women with normal ovaries . Main clinical , biological and ultrasonographic markers of PCOS were assessed during the early follicular phase . RESULTS The mean FNPO of follicles 2 - 5 mm in size was significantly higher in polycystic ovaries than in controls , while it was similar within the 6 - 9 mm range . Setting the threshold at 12 for the 2 - 9 mm FNPO offered the best compromise between specificity ( 99 % ) and sensitivity ( 75 % ) . Within the 2 - 5 mm follicular range , we found significant positive relationships between the FNPO and and rogens . The FNPO within the 6 - 9 mm range was significantly and negatively related to body mass index and fasting insulin serum level . CONCLUSIONS We propose to modify the definition of polycystic ovaries by adding the presence of > or = 12 follicles measuring 2 - 9 mm in diameter ( mean of both ovaries ) . Also , our findings strengthen the hypothesis that the intra-ovarian hyper and rogenism promotes excessive early follicular growth and that further progression can not proceed normally because of hyperinsulinism and /or other metabolic influence linked to obesity In order to determine which factors influence the large variations in sensitivity to gonadotrophins  witnessed in women with polycystic ovary syndrome ( PCOS ) , a prospect i ve study was conducted of the correlation between basal clinical and endocrinological features and gonadotrophin requirements of 20 women with clomiphene-resistant PCOS undergoing ovulation induction . Baseline evaluation of  serum concentrations of luteinizing hormone ( LH ) , follicle stimulating hormone ( FSH ) , testosterone , fasting insulin , insulin-like growth factor-1 ( IGF-1 ) , IGF binding protein-1 ( IGFBP-1 ) and sex hormone-binding globulin ( SHBG ) were performed before administering gonadotrophin-releasing hormone agonist ( GnRHa ) . Two weeks later , human menopausal gonadotrophin ( HMG ) was given in a st and ard individualized protocol according to ovarian response , until human chorionic gonadotrophin ( HCG ) was given . Serum concentrations of insulin , IGF-1 , and IGFBP-1 were unaffected by GnRHa . The BMI correlated positively with insulin and inversely with IGFBP-1 serum concentrations and insulin and IGFBP-1 were inversely correlated . The amount of HMG required correlated positively with BMI and insulin concentrations and inversely with IGFBP-1 in the whole group and these correlations were maintained in the sub-group of lean women . No correlation was observed between HMG requirements and IGF-1 or other hormones . Women with hyperinsulinaemia and low IGFBP-1 concentrations required significantly more HMG . Multiple regression analysis revealed that insulin concentration is the most significant determinant of HMG requirement even when dissociated from BMI . We concluded that requirements of HMG in PCOS is not merely determined by obesity but by a cardinal role of insulin concentrations which , when high , induce , hypothetically , a hyper and rogenic intrafollicular milieu In 20 patients with clinical ly , sonographically and endocrinologically proven polycystic ovary syndrome , ovulation induction with low doses of follicle stimulating hormone ( FSH ) was attempted by administration for 27 menstrual cycles . One ampule FSH was administered from day 3 onwards . If the ovarian response was inadequate after days 10 - 12 , the daily FSH dose was increased by half an ampule until ovulation induction . Of the cycles , 55.5 % were monofollicular , whereas 4 cycles had to be cancelled due to a multifollicular response or failure of ovarian stimulation . On average , 14.4 ampules was used , and human chorionic gonadotropin was given on day 16 . Seven pregnancies were established , with all of them ongoing at this writing . One twin pregnancy and one triplet pregnancy occurred . Even in polycystic ovary syndrome patients , low-dose administration of FSH allows safe stimulation , with a low incidence of ovarian hyperstimulation , a high pregnancy rate and an acceptably low risk of multiple pregnancies OBJECTIVE To compare the efficacy and safety of urinary FSH and recombinant FSH for ovulation induction in patients with clomiphene citrate-resistant , normogonadotropic , chronic anovulation . DESIGN Prospect i ve , r and omized trial . SETTING University-based infertility clinic . PATIENT(S ) Fifty-one women . INTERVENTION(S ) Subjects were r and omized to receive either urinary FSH ( 35 patients , 64 cycles ) or recombinant FSH ( 16 patients , 32 cycles ) . A maximum of three cycles using the low-dose step-up protocol with the same gonadotropin were undertaken . MAIN OUTCOME MEASURE(S ) Cumulative ovulation and pregnancy rates after three cycles , total gonadotropin dose , duration of stimulation , and single follicle development rate . RESULT ( S ) Cumulative ovulation rates were 89.3 % and 93.1 % for the urinary FSH and recombinant FSH groups , respectively . The threshold and total doses of FSH and the duration of stimulation were similar between the two groups . Significantly more single follicle development was noted in the recombinant FSH group . The respective clinical pregnancy rates per noncanceled cycles in the urinary FSH and recombinant FSH groups were 23.2 % and 27.6 % . There were three sets of twins in the urinary FSH group . No case of ovarian hyperstimulation syndrome was encountered . CONCLUSION ( S ) Urinary FSH and recombinant FSH are both efficient and safe for inducing ovulation with the low-dose step-up protocol Abstract Purpose : Our goal was to investigate the safety , effectiveness , and feasibility for the practicing physician of stepwise and low-dose administration of FSH in WHO group II anovulatory infertile women . Methods : Infertile female patients ( n=234 ) suffering from WHO group II anovulation , and who failed to became pregnant with clomiphene citrate  , were included in a multicenter , prospect i ve , clinical study of treatment with a protocol of chronic low-dose and small incremental rises with urinary purified or highly purified FSH . Follicular development was monitored with ultrasonographic scans . Results : The 234 patients received a total of 534 cycles of treatment , for a mean number of 2.3 treated cycles per patient . hCG was withheld in 65 ( 12.2 % ) cyles because of no response and in 28 ( 5.2 % ) cycles because of hyperresponse . Of the remaining 441 cycles , 419 ( 95 % ) were ovulatory , and in 198 ( 47.3 % ) of these cycles a single dominant follicle developed . There were 93 pregnancies ( 39.7 % per patient ) , for a cycle fecundity rate of 17.4 % . Cumulative conception rate after two treated cycles was 33.5 % . There were 14 ( 15 % ) pairs of twins and 10 ( 10.8 % ) spontaneous miscarriages . The prevalence of complications was low with no cases of severe OHSS . Basal LH/FSH ratio was significantly higher in the pregnant group of patients than in nonpregnant women . Conclusions : Stepwise and chronic low-dose administration of FSH is a safe and effective method for treatment of WHO group II anovulatory infertility , mainly in those patients having high LH/FSH ratios Treatment with low-dose follicle-stimulating hormone ( FSH ) is associated with a high rate of ovulation in anovulatory women with polycystic ovarian syndrome ( PCOS ) , but it is not clear whether the 
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Finally , pooled analysis did not find a significant association between testosterone and pregnancy rate .
In conclusion , the best available evidence , though limited , suggests that the most clinical ly useful predictors of gonadotrophin ovulation induction outcome in normogonadotrophic women are obesity and insulin resistance