Search

Background: Anti-Mullerian hormone (AMH) is a marker of ovarian reserve status and represents a good predictor of ovarian response to ovarian hyperstimulation. The aim of this study was to assess the accuracy of AMH and antral follicle count (AFC) as predictors of an excessive response in IVF/ICSI treatment., Methods: A systematic review and meta-analysis of the existing literature was performed. Studies were included if 2 × 2 tables for the outcome excessive response in IVF patients in relation to AMH/AFC could be constructed. Using a bivariate meta-analytic model, both summary point estimates for sensitivity and specificity were calculated, as well as summary ROC curves. Clinical value was analysed by calculating post-test probabilities of excessive response at optimal cut-off levels, as well as the corresponding abnormal test rates., Results: Nine studies reporting on AMH and five reporting on AFC were found. Summary estimates of sensitivity and specificity for AMH were 82 and 76%, respectively, and 82 and 80%, respectively, for AFC. Comparison of the summary estimates and ROC curves for AMH and AFC showed no statistical difference. Abnormal test rates for AMH and AFC amounted to ∼14 and 16%, respectively, at cut-off levels where test performance is optimal [likelihood ratio for a positive result (LR + ) > 8], with a post-test probability of ± 70%., Conclusions: Both AMH and AFC are accurate predictors of excessive response to ovarian hyperstimulation. Moreover, both tests appear to have clinical value. This opens ways to explore the potential of individualized FSH dose regimens based on ovarian reserve testing.

Background: The antral follicle count (AFC) and anti-Müllerian hormone (AMH) both represent age-related follicular decline quite accurately, although long-term follow-up studies are still lacking. The best ovarian reserve test would need only a single, cycle-independent measurement to be representative., Methods: To compare the inter- and intra-cycle stability of AFC and AMH, we used age-adjusted intra-class correlation coefficients (ICCs). To measure inter-cycle stability across a number of up to four menstrual cycles, we used data, prospectively collected for the purpose of an other study, from 77 regularly cycling, infertile women aged 24-40 years. AMH and AFC values were measured on cycle day 3. To study intra-cycle variability, we used data from a prospective cohort study of 44 regularly cycling volunteers, aged 25-46 years and measured AMH and assessed the AFC (2-10 mm) every 1-3 cycle days., Results: Between menstrual cycles, AFC and AMH varied between 0 and 25 follicles (median 10), and 0.3 and 27.1 ng/ml (median 4.64). The difference in age-adjusted ICC between AMH [ICC, 0.89 (95% CI, 0.84-0.94)] and AFC [ICC, 0.71 (95% CI, 0.63-0.77)] was 0.18 (95% CI, 0.12-0.27). For the intra-cycle variation, 0-43 antral follicles (median 7) were counted per volunteer. The difference in age-adjusted ICC between AMH [ICC, 0.87 (95% CI, 0.82-0.91)] and AFC [ICC, 0.69 (95% CI, 0.46-0.82)] was 0.18 (95% CI, 0.034-0.42)., Conclusions: Serum AMH demonstrated less individual intra- and inter-cycle variation than AFCs and may therefore be considered a more reliable and robust means of assessing ovarian reserve in subfertile women.

Background: Recombinant DNA technologies have been used to develop longer-acting therapeutic proteins. One approach is to introduce sequences containing additional glycosylation sites. Using this technique, a new chimeric gene has been developed containing the coding sequences of the FSH beta-subunit and the C-terminal peptide of the hCG beta-subunit, which bears four O-linked oligosaccharide binding sites. Co-expression of the alpha-subunit and the chimeric FSH beta-subunit produces a new recombinant molecule, named corifollitropin alfa, with a prolonged elimination half-life and enhanced in vivo bioactivity compared with wild-type FSH., Methods: Medline searches by subject and additional searching by hand., Results: Initial studies in pituitary suppressed female volunteers confirmed the extended half-life of the compound. Phase II studies have shown that corifollitropin alfa is able to induce and sustain multi-follicular growth for an entire week in women undergoing ovarian stimulation using GnRH antagonist co-treatment for IVF. Corifollitropin alfa regimens have been developed with dosages of 100 and 150 microg, for patients with body weight 60 kg, respectively., Conclusions: Corifollitropin alfa is the first long-acting hybrid molecule with sustained follicle-stimulating activity developed for the induction of multi-follicular growth along with GnRH antagonist co-treatment for IVF. This new treatment option may be simpler and more convenient for patients compared with conventional long protocols of daily FSH injections in combination with GnRH agonist co-treatment. The safety and efficacy of such regimens is currently being evaluated in large comparative phase III clinical trials. The development of corifollitropin alfa is the first step towards a new generation of recombinant gonadotrophins.

For women aged 41-43 years old, success rates in IVF are generally poor. This study aimed to assess cumulative live birth rate related to treatment costs over a maximum of three IVF cycles in selected women who were considered to still have adequate ovarian reserve. Fifty-five patients (38% of the total cohort, n = 144) were excluded from IVF treatment based on low antral follicle count (<5 follicles) and/or elevated basal FSH (>15 IU/l). Of those admitted, 66 (74%) actually started and completed a total of 125 IVF/intracytoplasmic sperm injection cycles. Treatment resulted in 10 live births (8% per cycle). Kaplan-Meier survival analysis revealed a realistic cumulative live birth rate after three cycles of 17%. The direct medical costs per live birth were calculated to be approximately 44,000 euro. These results show that selection towards favourable ovarian reserve status in the female age group 41-43 years yielded disappointing results in terms of cumulative live birth rates after IVF. In view of the costs raised per live birth, improvement of selection parameters for treatment in this age group is warranted.

In a first feasibility study, the efficacy and safety of a single dose of recombinant long-acting FSH (FSH-CTP) were investigated in in vitro fertilization (IVF) patients undergoing controlled ovarian stimulation with a flexible GnRH antagonist protocol. Eligible subjects were randomized to receive a single dose of 120 micro g (n = 25), 180 microg (n = 24), or 240 microg (n = 25) corifollitropin alfa (FSH-CTP) or to start daily fixed doses of 150 IU recombinant FSH (rFSH) (n = 24, reference). Subjects who received a single dose of FSH-CTP continued 1 wk after injection (treatment d 8) with fixed daily doses of 150 IU rFSH (Puregon/Follistim) until the day of triggering final oocyte maturation. The terminal half-life of FSH-CTP was, on average, 65 h and dose independent. Cycle cancellation before human chorionic gonadotropin (hCG) administration occurred in only three subjects treated with FSH-CTP. The median duration of stimulation was 10.0 d in each FSH-CTP group and 9.0 d in the daily rFSH group. The total number of follicles at least 11 mm at stimulation d 8 and at the day of hCG administration tended to increase with dose of FSH-CTP, although a significant dose-response relationship was revealed only for the number of follicles at least 15 mm on the day of hCG (P = 0.03). Serum estradiol levels and inhibin-B levels were not significantly different between the four groups on d 8 and on the day of hCG. In total, 12 subjects (17.6%) in the FSH-CTP groups and two subjects (8.3%) in the rFSH group experienced a premature LH rise (defined as LH >or= 10 IU/liter) before the start of the GnRH antagonist (P value not significant between groups). This relatively high incidence of women demonstrating an early LH rise in the FSH-CTP groups may be related to the higher initial rises of serum estradiol and the use of a flexible GnRH antagonist protocol. The mean number of oocytes recovered per started cycle was higher in FSH-CTP-treated subjects compared with rFSH-treated subjects (significant at P = 0.03 for the 240- microg FSH-CTP group), but no difference could be noted between the number of good quality embryos (range of means, 3.8-4.8 per attempt), and equal numbers of embryos were available for embryo transfer. In summary, FSH-CTP appeared to be a potent inducer of multiple follicular growth; additional research will be needed to select the optimal FSH-CTP dose and treatment time interval.

Background: The purpose of this study was to compare the predictive capacity of several markers of reproductive age in normal women., Methods: Healthy female volunteers (n = 162) aged 25-46 years with proven, normal fertility and regular menstrual cycles were recruited. In this selected group, chronological age was assumed to approximate reproductive age and, therefore, was taken as the proxy-variable for reproductive age. The number of antral follicles with 2-10 mm diameter, total ovarian volume, total follicular volume, mean follicular volume, and volume of either the smallest or largest ovary were estimated by transvaginal sonography of the ovaries. Serum levels of early follicular FSH, estradiol and inhibin B, as well as the response of estradiol and inhibin B to exogenous GnRH agonist administration (GAST), were also evaluated., Results: Regression analysis revealed that the antral follicle number showed the highest correlation with age (r = -0.68, P = 0.001), and explained 46% of its variance. All other variables, except inhibin B, were moderately correlated with age. Responses of estradiol and inhibin B to the GnRH agonist were moderately correlated with age, but highly correlated with the number of antral follicles., Conclusions: It is concluded that the number of antral follicles has the closest association with chronological age in normal women with proven fertility. As stimulated estradiol and inhibin B clearly reflect the size of the antral follicle cohort, the GAST may be considered the second best single test to predict reproductive age.

The great majority of human oocytes is destined to undergo atresia. Only follicles able to respond to stimulation by follicle-stimulating hormone (FSH) will enter the final stage of development and ovulate. While the role of FSH in early follicle development is unclear, late follicular development is FSH-dependent. FSH levels increase during the luteo-follicular transition and give rise to continued growth of a cohort of follicles. In the normo-ovulatory cycle, one follicle achieves a diameter of >8 mm and produces high concentrations of estradiol. In response to negative feedback from rising estradiol and inhibin levels, FSH levels fall in the late follicle phase. The dominant follicle has increased sensitivity to the falling FSH levels and continues growing. Follicles that initiate the latter stages of development after FSH levels begin to fall undergo atresia. The duration of this FSH window during which FSH levels are above the threshold required to stimulate ongoing development determines the number of follicles that can develop to the pre-ovulatory stage. Recognition of this concept has resulted in new approaches in ovulation induction treatment and ovarian hyperstimulation therapy for in vitro fertilization (IVF).

This prospective, randomized trial in normo-ovulatory women was designed to test whether administration of low-dose exogenous FSH initiated during the early, mid to late follicular phase can induce multiple dominant follicle development. Forty normal weight women (age 19-35 years, cycle length 25-32 days) participated. A fixed dose (75 IU/day) of recombinant FSH was started on either cycle day 3 (n = 13), 5 (n = 13) or 7 (n = 14) until the induction of ovulation with human chorionic gonadotrophin. Frequent transvaginal ultrasound scans and blood sampling were performed. Multifollicular growth occurred in all groups (overall in 60%), although day 7 starters showed less multifollicular growth. Age, cycle length and initial FSH and inhibin B concentrations were similar between subjects with single or multiple follicle development. However, for all women the lower the body mass index (BMI), the more follicles emerged (r = -0.44, P = 0.007). If multifollicular growth occurred, the length of the luteal phase was reduced (P = 0.002) and midluteal serum concentrations of LH (P = 0.03) and FSH (P = 0.004) were decreased and oestradiol (P = 0.002) and inhibin A (P = 0.01) were increased. In conclusion, interference with decremental serum FSH concentrations by administration of low dose FSH starting on cycle day 3, 5 or as late as day 7, is capable of disrupting single dominant follicle selection. The role of BMI in determining ovarian response suggests that differences in pharmacokinetics of exogenous FSH are involved. Multifollicular growth per se has a distinct effect on luteal phase characteristics. These observations may be relevant for the design of mild ovarian stimulation protocols.

Objective: To investigate relations between dose of GnRH antagonist and follicular phase characteristics., Design: Randomized controlled multicenter trial., Setting: Tertiary referral fertility centers., Patient(s): Three hundred and twenty-nine IVF patients., Intervention(s): Ovarian stimulation for IVF with recombinant FSH starting on cycle day 2. From cycle day 7 onwards, cotreatment was provided with 0.0625, 0.125, 0.25, 0.5, 1.0, or 2.0 mg/d GnRH antagonist., Main Outcome Measure(s): Number of follicles, total follicular surface area, gonadotropin, and serum steroid concentrations., Result(s): In 311 patients, similar follicular growth was observed in all treatment groups. FSH levels increased during the follicular phase. Late follicular phase LH, androstenedione (AD), and E(2) levels showed a GnRH antagonist dose-related decrease (P<0.05). Late follicular phase E(2) levels correlated with total follicular surface area, AD, LH, and FSH (all P<0.001). Increasing GnRH antagonist doses exhibited additional suppressive action on E(2) levels., Conclusion(s): Follicular growth was unaffected by the dose of GnRH antagonist. A rise in follicular phase FSH serum concentrations during the follicular phase, largely related to exogenous FSH, enabled ongoing follicular growth in all treatment groups. The effect of GnRH antagonist on late follicular phase E(2) levels could not be exclusively attributed to suppression of LH.

Current ovarian stimulation regimens for IVF are complex and not without risk. Increasing our knowledge of the physiology of follicle development and dominant follicle selection may enable the design of less complex, safer and cheaper ovarian stimulation regimens for IVF. Decremental serum FSH concentrations during the follicular phase of the menstrual cycle are required for single dominant follicle selection. Only the most mature follicle will continue its development due to increased sensitivity for stimulation by FSH. FSH stimulation becomes insufficient for less mature follicles and remaining cohort follicles will therefore go into atresia. The number of days during which FSH is above the threshold for stimulation of follicle development is limited, resulting in a narrow FSH window. More medium sized and large pre-ovulatory follicles and increased oestradiol output can be induced by the administration of small doses of exogenous FSH during the mid- to late follicular phase, preventing the physiological decrease in FSH stimulation. Intervention with decremental serum FSH concentrations in combination with gonadotrophin-releasing hormone (GnRH) antagonists to prevent a premature rise in serum LH may induce ongoing growth of multiple follicles sufficient for IVF. The benefits and risks of these minimal hyperstimulation protocols require further evaluation.

The pool of primordial follicles present in the female ovary reaches its maximum number around 20 weeks of gestational age and then decreases in a logarithmic fashion throughout life until complete depletion occurs around the age of the menopause. Reproductive life is initiated when less than 10% (0.5 million) of primordial follicles are left. The entire growth trajectory of the follicle takes at least 3 months. Follicle growth up to the antral stage occurs during fetal life and infancy. While the role of gonadotropins in early follicular development remains controversial, the last 2 weeks of development are FSH dependent. The intercycle rise in FSH and decreasing levels thereafter are crucial for recruitment of a cohort of healthy, early antral follicles and subsequent single dominant selection. Following puberty, anovulation may persist for years and this may presage the development of adult anovulatory infertility. The menopause is preceded by a period of reduced fertility. The development of reliable and sensitive markers for ovarian ageing will be the challenge of the near future., (Copyright 2000 S. Karger AG, Basel)

An understanding of the factors which determine initiation of follicle growth, recruitment and dominant follicle selection may increase our understanding of the underlying process of ovarian aging. In this article, these aspects of the normal menstrual cycle are reviewed. The morphological and endocrinological development in the early follicle is described from the primordial follicle stage. The degree of follicle-stimulating hormone (FSH) dependency is discussed, as is the relationship of estradiol (E2) production to follicle diameter. The principles governing mono-follicular selection are outlined, and the FSH 'threshold' and 'window' concepts are highlighted. Maximum FSH levels in the early follicular phase are shown to be variable between individuals. The relevance of this and the means by which individual sensitivity to FSH may be altered at the ovary in the context of ovarian aging are discussed.

According to the threshold concept, FSH concentrations need to surpass a distinct level to stimulate ovarian follicle growth. The window concept stresses the significance of a limited duration of elevated FSH levels above the threshold for single dominant follicle selection. The aim of this study was to investigate effects on follicle growth of increased FSH levels, differing in duration and magnitude of elevation, during the follicular phase. Twenty-three normo-ovulatory (cycle length, 26-31 days), young (age, 20-31 yr) women volunteered for this study. In all subjects a series of daily transvaginal sonography scans of the ovaries and blood sampling [for FSH and estradiol (E2) determinations] were performed during two consecutive cycles. The first study cycle (control cycle) started 10 days after urinary assessment of the LH surge in the preceding cycle (DayLH) and was concluded on the day of ovulation assessed by transvaginal sonography scans. The second series of daily monitoring (intervention cycle) started 10 days after DayLH in the control cycle. After randomization, subjects received either 375 IU urinary FSH, s.c., as a single injection on Day(LH+14) (group A; n = 11) or 75 IU daily from Day(LH+19) until Day(LH+23) (group B; n = 12). In group A, FSH levels increased on the day after injection to a median concentration of 10.1 IU/L, which was 1.9 times higher (P < 0.01) than levels on matching days during the control cycle. Concentrations returned to basal levels 3 days after injection. In group B, a moderate elevation of FSH concentrations (15% increase; P < 0.05) was observed compared to levels during the control cycle. In group A, E2 concentrations increased (P = 0.03) 1 day after FSH injection and returned to baseline levels within 2 days. In group B, E2 levels started to increase after the first injection of FSH and remained significantly higher (P < 0.01) during the following 5 days compared to those on matching days in the control cycle. Compared to matching days in the control cycle an increased number of follicles 8-10 mm in size was found in group A (P < 0.01) during the period from Day(LH+14) until Day(LH+19), without an increase in follicles 10 mm or larger thereafter. In contrast, in group B, the numbers of both 8- to 10-mm and 10-mm or larger follicles were higher during the period from Day(LH+19) until Day(LH+24) in group B (P = 0.02 and P < 0.01, respectively). Results from the present study suggest that a brief, but distinct, elevation of FSH levels above the threshold in the early follicular phase does not affect dominant follicle development, although the number of small antral follicles did increase. In contrast, a moderate, but continued, elevation of FSH levels during the mid to late follicular phase (effectively preventing decremental FSH concentrations) does interfere with single dominant follicle selection and induces ongoing growth of multiple follicles. These findings substantiate the FSH window concept and support the idea of enhanced sensitivity of more mature follicles for stimulation by FSH. These results may provide the basis for further investigation regarding ovulation induction treatment regimens with reduced complication rates due to overstimulation.

Both luteinizing hormone (LH) and follicle-stimulating hormone (FSH) are required for follicle development and oestrogen production. Moreover, under normal conditions a close association between dominant follicle size and serum and intrafollicular oestradiol levels is observed. With the recent availability of human recombinant FSH (recFSH), it was possible for the first time to study effects of FSH alone, in the complete absence of endogenous or exogenous LH, on ovarian function. Recent studies applying recFSH in hypogonadotrophic women have shown convincingly that normal growth of follicles up to the preovulatory stage occurs despite extremely low oestradiol levels, in keeping with previous observations using exogenous gonadotrophins in women incapable of synthesizing oestradiol due to steroid enzyme abnormalities. Insufficient data are presently available in humans to conclude whether or not oocyte quality is compromised under these circumstances. It should, however, be realized that sufficient oestradiol levels are required for fertilization in vivo. Therefore LH, or human chorionic gonadotrophin (HCG), should be added to stimulation protocols in hypogonadotrophic individuals. These observations may also be relevant for monitoring of ovarian response during recFSH therapy, especially when combined with gonadotrophin-releasing hormone agonists for ovarian hyperstimulation for in-vitro fertilization.

Objective: The mechanism of dominant follicle selection remains obscure. We have investigated the association between follicle diameter and follicular steroid levels in individual human ovarian follicles throughout the menstrual cycle., Design: Fluid from ovarian follicles (n = 326) was obtained in vivo during surgery from 55 regularly cycling women with proven fertility. Follicles were divided into dominant (diameter >9 mm, n = 45) and non-dominant (diameter < or = 9 mm, n = 281) based on ultrasound measurements., Measurements: Fluid was assayed for oestradiol (E2), androstenedione (AD), and progesterone (P)., Results: Median P and E2 levels were significantly lower (P < 0.0001) and AD levels significantly higher (P = 0.03) in non-dominant as compared to dominant follicles. In non-dominant follicles AD (r = 0.14, P = 0.02), but not P and E2, levels were correlated to follicular diameter, and significant changes in steroid concentrations across the menstrual cycle were absent. In dominant follicles, diameter was positively correlated with P and E2 (P < 0.001) levels, and inversely correlated with AD concentrations (P = 0.01)., Conclusions: Results indicate that (1) intrafollicular oestradiol concentrations rise only in follicles exceeding 9 mm in diameter and correlate with the diameter of these dominant follicles, suggesting that significant increase in aromatase enzyme activity occurs only in the dominant follicle (2) a cycle-independent accumulation of androstenedione with size occurs in non-dominant follicles, and (3) progesterone production occurs in the largest dominant follicles only, suggesting a limited, if any, role for progesterone during follicle development.

Objective: To study the relationship between decreasing serum FSH levels in the follicular phase of the normal menstrual cycle and follicle development by means of transvaginal sonography and E2 production., Design: Daily blood samples were taken and transvaginal sonography was performed every other day in 16 normal regularly cycling female volunteers., Main Outcome Measure: Serum levels of FSH, LH, E2, and P and follicle diameter by transvaginal sonography., Results: A distinct variability in individual maximal early follicular phase FSH plasma levels was observed (range 4.4 to 11.2 mIU/mL [conversion factor to SI unit, 1.000]). Differences in maximum FSH levels did not correlate with other endocrine or sonographic follicular phase characteristics. The follicular phase FSH decrease (from median 6.6 to 2.9 mIU/mL [conversion factor to SI unit, 1.000]) took place between cycle day 5 and 13 and was linear (0.5 +/- 0.05 mIU/mL per day; mean +/- SD). A significant correlation was found between serum FSH decrease and E2 increase. The day of sonographic appearance of a dominant follicle (median cycle day 8) did correlate with the first rise of the E2 plasma concentration., Conclusions: The present study suggests that even in women exhibiting normal ovarian function a 2.5-fold difference in FSH threshold concentrations for follicle recruitment does occur. Moreover, the magnitude of decrease in serum FSH concentrations during the follicular phase affects dominant follicle E2 production. The sonographic appearance of the dominant follicle is associated with a rise in serum E2 levels.

Improved knowledge with regard to ovarian abnormalities in PCOS should help to classify patients suffering from this heterogeneous syndrome and may help to improve treatment outcome. Based on various observations, as previously discussed, it seems reasonable to assume that follicle development progresses to a size of 6-8 mm without an associated increase in estrogen biosynthesis. This is the size where dominant follicle selection takes place under normal conditions where follicle growth is arrested in polycystic ovaries. It may be hypothesized that under normal conditions FSH action is enhanced locally (for instance by changes in the IGF system) in the dominant follicle, whereas in polycystic ovaries this intraovarian upregulation is disrupted. Normal early antral follicle development is also confirmed by morphology studies. The classical concept of disturbed induction of the aromatase enzyme in PCOS should be questioned, since recent observations indicate that follicles may grow without a concomitant increased in intraovarian estrogens.

The aim of this study was to investigate the late follicular phase of seven gonadotrophin-treated patients with polycystic ovary syndrome (PCOS) exhibiting monofollicular growth and to compare developmental characteristics with the dominant follicle in seven regularly cycling control women. Daily serum follicle-stimulating hormone (FSH) levels in patients with PCOS decreased more rapidly compared to controls (-0.3 +/- 0.2 IU/day in controls versus -0.7 +/- 0.4 IU/day in PCOS; p < 0.02). No statistically significant differences were seen in daily increase (30% in controls and PCOS) and mean peak levels (825 +/- 94 pmol/l in controls versus 937 +/- 231 pmol/l in PCOS) of oestradiol (E2) serum levels when comparing both groups. Mean daily growth of the dominant follicle (1.7 +/- 0.4 mm in controls versus 1.9 +/- 0.6 mm in PCOS) was not significantly different. It is concluded from the present study that in patients with PCOS treated with gonadotrophin plus adjuvant gonadotrophin-releasing hormone agonist, development of a single follicle can occur using a decreasing dose regimen resulting in decreasing serum FSH levels. In addition, growth and oestrogen production by the dominant follicle in PCOS is not significantly different from follicle growth under normal conditions.

To evaluate the importance of luteinizing hormone (LH) for normal estrogen production and subsequent development of ovarian follicles, a woman with isolated gonadotropin deficiency (LH; 0.37 IU/L, FSH 1.2 IU/L) was monitored during recombinant human follicle-stimulating hormone (hFSHrec) administration with respect to ovarian follicular growth and steroid production. During the first week (75 IU/day hFSHrec im) a significant rise in serum FSH (4.9 IU/L) was observed in the absence of changes in serum estradiol (E2) concentrations (36-76 pmol/L). During the following five days 150 IU/day hFSHrec was administered resulting in a further increase of serum FSH levels (maximum 8.5 IU/L). Development of multiple follicles--maximum diameter 22 mm as observed by transvaginal sonography--emerged together with a minor rise in E2 levels (from 76 to 236 pmol/L) and with a minimal increase in endometrial thickness (below 6 mm). Six days following the last injection of hFSHrec, aspiration of 3 follicles (13, 15 and 18 mm) was performed and low intrafollicular androstenedione (AD) (less than 675 nmol/L) and E2 (less than 9400 pmol/L) concentrations as compared to normal follicles were found. These first data on hFSHrec administration in the human suggest that; a) FSH alone can induce growth of preovulatory follicles, b) follicle growth does occur in the presence of subnormal E2 levels, c) LH is needed for adequate AD biosynthesis as substrate for aromatase activity. This indicates that growth and steroidogenic granulosa cell activity may be differentially regulated.

Data presented in this study indicate that ovulation can be induced in patients with PCOS using a GnRH analogue combined with hMG in a decreasing dose regimen. Based on the observed decline in functional, medium sized follicles in the late follicular phase, it may be speculated that the risk of ovarian hyperstimulation during gonadotropin induction of ovulation in patients with PCOS can be reduced.

Transvaginal ultrasound examinations were performed in seven normally cycling women to characterize growth of nondominant follicles in both ovaries. Mean follicle number showed little variation throughout the menstrual cycle with no differences between dominant and nondominant ovaries. Up to 11 follicles (greater than or equal to 2 mm) were observed in any one ovary. From observations of the first appearance of the dominant follicle (mean size 9.9 +/- 3.0 [SD] mm), selection was assumed to take place on cycle day 6.3 +/- 2.3. The diameter of nondominant follicles always remained less than 11 mm. Growth of small follicles was established in both dominant and nondominant ovaries up to the time of selection. The late follicular and luteal phases were characterized by a decrease in mean growth slopes of nondominant follicles in the dominant ovary only. These observations may provide in vivo evidence for the concept of intraovarian paracrine mechanisms and may have implications for the sonographic diagnosis of anovulation and monitoring of ovulation induction.