Oocyte matched follicular fluid anti-Müllerian hormone is an excellent predictor of live birth after fresh single embryo transfer.

STUDY QUESTION: What is the relationship between the anti-Müllerian hormone (AMH), gonadotropin and androgen concentrations within a single follicle and live birth after ICSI and a transfer of an embryo developed from the matched oocyte? SUMMARY ANSWER: Among the analysed markers on the day of oocyte retrieval, AMH concentration in follicular fluid (FF) is a predictor of live birth after single embryo transfer (SET). WHAT IS KNOWN ALREADY: High serum concentrations of AMH and low FSH concentrations have been associated with a high chance of pregnancy after ART. Whether there are differences in the hormonal milieu for individual follicles and whether this impacts the laboratory and clinical outcomes for the individual oocyte developing within that follicle are unknown. STUDY DESIGN, SIZE, DURATION: This prospective cohort study included 322 individual FF samples from 199 infertile women scheduled for ICSI/SET over an 18-month period. Of these women, 76 provided a single FF sample, while 123 women contributed two FF samples taken from two different follicles. PARTICIPANTS/MATERIALS, SETTING, METHODS: The first follicle aspirated in each ovary on the day of oocyte retrieval had the FF aspirated; the individual cumulus-oocyte complex (COC) was tracked, and the associated FF was stored at -80°C. FF AMH, FSH, LH, testosterone (T) and androstenedione (A2) levels were measured by mass spectrometry (androgens) and immunoassays. The laboratory and clinical outcomes for each individual oocyte were related to their unique follicle hormone concentrations. MAIN RESULTS AND THE ROLE OF CHANCE: Of the 322 oocytes with paired FF samples, 70 (21.7%) oocytes did not fertilise. From the remaining 252 2PN embryos, 88 (34.9%) were transferred as single embryos on Day 3; of the remaining 164, 78 developed into blastocysts, and 18 single blastocyst transfers were performed. Thus, a total of 106 transferred embryos had matching FF samples. An analysis of these individual FF concentrations revealed that AMH concentrations were higher in follicles in which the oocyte developed into a top quality (TQ) blastocyst (6.33 ± 5.52 ng/ml) and whose transfer led to live birth (7.49 ± 5.03 ng/ml) than those in which there was a failure of fertilisation (3.34 ± 2.21 ng/ml). In contrast, follicular FSH concentrations were the lower for oocytes that resulted in a TQ blastocyst (5.36 ± 2.20 mIU/ml) and live birth (5.60 ± 1.41 mIU/ml) than for oocytes that failed to fertilise (9.06 ± 3.36 mIU/ml). FF AMH was the only studied marker that increased the chance of live birth (odds ratio: 1.93 [95% CI: 1.40-2.67], P < 0.001). The receiver operating characteristic analysis showed that FF AMH levels predicted live birth with a very high sensitivity (91.2%), specificity (91.7%) and an excellent AUC value of 0.954, whereas serum AMH level only had a fair (AUC = 0.711) significance as a predictor for live birth after ICSI/SET. The predictive capabilities of the interfollicular markers were not limited to the TQ embryos or blastocysts; they applied to all SET cycles. LIMITATIONS, REASONS FOR CAUTION: Whether an altered intrafollicular hormonal environment reflects the developmental capacity of the oocyte or defines cannot be determined from this cross-sectional analysis. Inclusion of 21 subjects with polycystic ovary syndrome (PCOS) may have biased the findings due to a unique intrafollicular milieu associated with PCOS. WIDER IMPLICATIONS OF THE FINDINGS: Our results suggest that highly competent human oocytes have an FF composition of AMH, FSH, T and A2 that is close to that in a natural cycle. Also, the relationships between intrafollicular AMH, gonadotropin and androgen levels in the same follicle support the hypothesis that FF AMH concentration may reflect granulosa cell proliferation during gonadotropin-stimulated follicle growth. Finally, the serum AMH concentration is markedly lower than the FF AMH concentration, with a moderate correlation between serum and FF AMH, implying ovarian follicle autonomy with regards to its secretory products. STUDY FUNDING/COMPETING INTEREST(S): The National Science Centre of Poland supported this work (grant number: N N407 217 040). The authors declare that there is no conflict of interest regarding the publication of this article.

Medical management of endometriosis: emerging evidence linking inflammation to disease pathophysiology.

Progesterone action normally mediates the balance between anti-inflammatory and proinflammatory processes throughout the female reproductive tract. However, in women with endometriosis, endometrial progesterone resistance, characterized by alterations in progesterone responsive gene and protein expression, is now considered a central element in disease pathophysiology. Recent studies additionally suggest that the peritoneal microenvironment of endometriosis patients exhibits altered physiological characteristics that may further promote inflammation-driven disease development and progression. Within this review, we summarize our current understanding of the pathogenesis of endometriosis with an emphasis on the role that inflammation plays in generating not only the progesterone-resistant eutopic endometrium but also a peritoneal microenvironment that may contribute significantly to disease establishment. Viewing endometriosis from the emerging perspective that a progesterone resistant endometrium and an immunologically compromised peritoneal microenvironment are biologically linked risk factors for disease development provides a novel mechanistic framework to identify new therapeutic targets for appropriate medical management.

Naltrexone treatment in clomiphene resistant women with polycystic ovary syndrome.

BACKGROUND: Endogenous opiates may affect various aspects of reproductive and metabolic function in patients with polycystic ovary syndrome (PCOS). This study evaluated long-term inhibition of the opioid system using naltrexone in clomiphene citrate (CC)-resistant women with PCOS. METHODS: A group of 30 infertile females with PCOS were evaluated; all subjects were obese, hyperandrogenic and hyperinsulinemic; 16 patients were amenorrhic and 14 were oligomenorrhic. All subjects received natrexone (50 mg p.o. daily) for 6 months. Patients who did not ovulate after 12 weeks of naltrexone monotherapy, also received CC (starting at 50 mg/day for 5 days and, for non-responders, increasing it up to 150 mg/day). RESULTS: Of the 30 women, 3 ovulated during naltrexone monotherapy and 19 of the remaining 27 ovulated during naltrexone + CC therapy. There were no conceptions during naltrexone monotherapy, but 9 of 27 women (33.3%) conceived during naltrexone + CC; there was one missed abortion at 9 weeks, one preterm delivery at 34 weeks and seven term live births. Naltrexone therapy was also followed by significant reductions in BMI, fasting serum insulin, luteinizing hormone (LH), LH/follicle-stimulating hormone ratio and testosterone. CONCLUSIONS: In this preliminary trial, naltrexone improved endocrine and metabolic function in women with CC-resistant PCOS. Furthermore, naltrexone restored CC sensitivity in the majority of subjects, resulting in a significant number of pregnancies.

The effect of a pure antiandrogen receptor blocker, flutamide, on the lipid profile in the polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is one of the most common endocrinopathies affecting women of reproductive age; it is associated with hyperandrogenism, hyperinsulinemia, and dyslipidemia. This study was designed to assess the long term effects of a pure androgen receptor blocker, flutamide, on the lipid profile in women with PCOS and to examine the possible mechanisms by which androgens may exert their influence. Seventeen women with PCOS (10 obese and 7 lean) were studied. All subjects received a 12-week course of oral flutamide (500 mg/day). The baseline and posttreatment evaluations included lipid profile, androgen levels, insulin sensitivity, and serum catecholamine determinations. The primary outcome was the change in the ratio of low density lipoproteins (LDL) to high density lipoproteins (HDL). Treatment with flutamide was associated with a significant decrease in the LDL/HDL ratio by 23% (P = 0.005), in total cholesterol by 18% (P < 0.0001), in LDL by 13% (P = 0.002), and in triglycerides by 23% (P = 0.002). Flutamide treatment was also associated with a trend toward an increase in HDL (by 14%; P = 0.14). The effects on lipid profile were found regardless of obesity and were not associated with a change in weight. Furthermore, actions of flutamide on lipid metabolism were not associated with significant changes in circulating adrenaline or noradrenaline, glucose metabolism, or insulin sensitivity. This report has demonstrated for the first time that treatment with the pure antiandrogen, flutamide, may improve the lipid profile and that this effect may be due to direct inhibition of androgenic actions.

Effects of transforming growth factors-alpha and -beta on proliferation and apoptosis of rat theca-interstitial cells.

Ovarian development, follicular growth and atresia require mechanisms regulating proliferation and death of ovarian cells including theca-interstitial (T-I) cells. Transforming growth factors-alpha and -beta (TGF-alpha and TGF-beta) are well recognized local modulators of T-I function. This study was performed to evaluate the effects of TGF-alpha and TGF-beta on ovarian T-I cell proliferation, differentiation and apoptosis. T-I cells from immature Sprague-Dawley rats were purified and incubated in chemically defined media. Proliferation was assessed by [3H]thymidine incorporation assay and by cell counting. Steroidogenically active cells were identified histochemically by detection of 3beta-hydroxysteroid dehydrogenase (3beta-HSD) activity. DNA was extracted and apoptosis was identified by detection of internucleosomal DNA cleavage producing the characteristic 'ladder pattern' of low-molecular weight (LMW) DNA following agarose gel electrophoresis. Quantification of apoptosis was carried out with the aid of 3'-end labeling of DNA fragments with [32P]-dideoxy-ATP. TGF-alpha and TGF-beta stimulated [3H]thymidine incorporation by 2.2- to 3.1-fold and 1.7- to 3.4-fold respectively (P<0.005). A combination of TGF-alpha and TGF-beta produced a synergistic increase in DNA synthesis by 6.7-fold (at 1 ng/ml of each TGF-alpha and TGF-beta; P<0.001) and tenfold (at 10 ng/ml of each TGF-alpha and TGF-beta; P<0.001). Cell counting revealed that TGF-alpha increased the total number of cells 2.8-fold and TGF-beta 2.8-fold. The combination of TGF-alpha and TGF-beta increased the total cell count 3.2-fold, compared with control (P<0.05). The percentage of the steroidogenically active cells was 37+/-9% (mean+/-s.e.m. ) in the control cultures, 50+/-5% in the presence of TGF-alpha, 42+/-8% in the presence of TGF-beta, and 47+/-13% in the presence of both TGF-alpha and TGF-beta. TGF-alpha decreased apoptosis by 63+/-14% (P=0.02) while TGF-beta had no statistically significant effect. TGF-alpha in combination with TGF-beta produced the greatest inhibition of apoptosis by 73+/-8% (P=0.01). These findings demonstrate that TGF-alpha and -beta stimulate proliferation of both steroidogenically active and inactive T-I cells. Furthermore, TGF-alpha alone and in combination with TGF-beta protects T-I cells from apoptotic death. These effects of TGFs may be important in physiologic maintenance of ovarian mesenchymal growth and homeostasis as well as in pathophysiologic conditions associated with excessive growth of the T-I compartment, such as polycystic ovary syndrome.

Direct effects of clomiphene citrate on the steroidogenic capability of human granulosa cells.

The effects of clomiphene citrate (CC), 17 beta-estradiol (E2), and human chorionic gonadotropin (hCG) on the accumulation of progesterone (P) and 20 alpha-hydroxy-4-pregnen-3-one (20 alpha-OHP) in cultured human granulosa cells (GC) were examined. In addition, the metabolism of [4-14C]pregnenolone and accumulation of [4-14C]P in response to CC and E2 were determined. The authors conclude the following: (1) the dose-dependent inhibition of P and 20 alpha-OHP production by CC in GC was not reproduced by E2, (2) hCG abolished these effects of CC, (3) these inhibitory actions of CC were not associated with altered 3 beta-hydroxysteroid dehydrogenase activity nor P catabolism indicating that, (4) these actions by CC on the GC occur at some step(s) during steroidogenesis preceding the formation of pregnenolone. These findings may explain, at least in part, the luteal deficiency experienced by women treated with CC, and they also provide a rationale for the use of hCG supplementation during ovulation induction with CC.

Metformin therapy decreases hyperandrogenism and hyperinsulinemia in women with polycystic ovary syndrome.

OBJECTIVE: To evaluate the effects of 12 weeks of metformin therapy on hormonal and clinical indices in polycystic ovary syndrome (PCOS). DESIGN: Prospective study. SETTING: University hospital. PATIENT(S): Thirty-nine women with PCOS and fasting hyperinsulinemia. INTERVENTION(S): Twelve weeks of therapy with oral metformin (500 mg three times per day). MAIN OUTCOME MEASURE(S): Levels of insulin, T, DHEAS, insulin-like growth factor-I (IGF-I), gonadotropins, and sex hormone-binding globulin (SHBG); and clinical symptoms including acne, hirsutism, and length of the menstrual cycle were assessed before and after treatment with metformin. RESULT(S): Metformin therapy resulted in a significant decrease in fasting insulin and total T and an increase in SHBG, leading to a decrease in the free T index. In addition, there was a significant decline in mean body mass index, waist-hip ratio, hirsutism, and acne, as well as an improvement in the menstrual cycle. No changes in LH and LH-FSH ratio were observed. Multiple regression analysis demonstrated that the greatest decline of T and free T index in response to metformin was observed among patients with the most pronounced hyperandrogenemia. Subjects with elevated DHEAS differed from those with normal DHEAS in their responses to metformin treatment. Women with high DHEAS exhibited less improvement of menstrual cycle regularity, no change in hirsutism, and an increase in levels of IGF-I after treatment. CONCLUSION(S): Metformin treatment of women with PCOS results in a decline of insulin as well as total and bioavailable T, leading to significant improvement of clinical manifestations of hyperandrogenism. Responses to metformin are related to the severity of hyperandrogenemia and to adrenal function.

Comparison of intrauterine insemination with timed intercourse in superovulated cycles with gonadotropins: a meta-analysis.

OBJECTIVE: To compare timed intercourse and IUI with the husband's sperm in patients with unexplained infertility who are undergoing superovulation with gonadotropins. DESIGN: Meta-analysis. All published reports of randomized, prospective studies with an English-language abstract extracted from MEDLINE were analyzed. A crossover search was done from the papers obtained. SETTING: Academic center. PATIENT(S): Couples with unexplained infertility. INTERVENTION(S): Meta-analysis of studies evaluating patients superovulated with gonadotropins and randomized for timed intercourse or IUI. MAIN OUTCOME MEASURE(S): Pregnancy rates (PRs) were obtained. The common odds ratio (OR) and 95% confidence intervals (95% CI) were calculated. RESULT(S): There were 49 pregnancies in 431 cycles of timed intercourse (11.37%), whereas there were 110 pregnancies in 549 cycles of IUI (20.04%). The PRs for IUI were significantly increased compared with those for timed intercourse in superovulation cycles (common OR = 1.84; 95% CI = 1.30-2.62). CONCLUSION(S): On the basis of the meta-analysis of 980 cycles in randomized and prospective studies, a patient's chances of becoming pregnant are greater with IUI with her husband's sperm than with timed intercourse in cycles superovulated with gonadotropins.

Insulin and insulin-like growth factor I stimulate the proliferation of human ovarian theca-interstitial cells.

OBJECTIVE: To determine whether insulin and insulin-like growth factor I (IGF-I) affect the proliferation of human theca-interstitial cells. DESIGN: In vitro assays. SETTING: University laboratory. PATIENT(S): Premenopausal women undergoing oophorectomy for benign conditions. INTERVENTION(S): Purified theca-interstitial cells were cultured in chemically defined media with or without insulin and IGF-I. MAIN OUTCOME MEASURE(S): The proliferation of cells was evaluated by determination of [3H] thymidine incorporation and cell counting. RESULT(S): Insulin and IGF-I stimulated DNA synthesis by theca-interstitial cells in a dose-dependent fashion. Insulin-like growth factor I had a greater potency than did insulin. The effects of both approached, but did not reach, the level of DNA synthesis observed in cultures exposed to 10% fetal bovine serum. Direct counting of theca-interstitial cells revealed that IGF-I significantly increased the total number of cells (36% above control), whereas insulin induced a modest and statistically nonsignificant increase in the cell number (14% above control). CONCLUSION(S): The present results support the hypothesis that insulin and IGF-I promote the mitotic activity of theca-interstitial cells. These effects may represent mechanisms that lead to hyperplasia of the thecal/stromal compartment in polycystic ovary syndrome.

Baseline cyst formation after luteal phase gonadotropin-releasing hormone agonist administration is linked to poor in vitro fertilization outcome.

OBJECTIVE: To investigate the prognostic significance of baseline ovarian cysts after luteal phase GnRH agonist (GnRH-a) administration for IVF-ET. DESIGN: All nondonor IVF-ET cycles in one program in which luteal phase GnRH-a was administered between July 1993 and January 1994 were assessed for the formation of baseline ovarian cysts defined as a mean diameter > or = 15 mm. Outcome data from the IVF cycles were compared between patients with and without baseline ovarian cysts. RESULTS: Of 78 IVF cycles, baseline cysts > or = 15 mm were noted in 26 cycles. Cycles in which cysts were formed were associated with significantly older patients with significantly higher baseline FSH values. Cycles in which cysts were present demonstrated fewer follicles, retrieved oocytes, and embryos. Cyst cycles also demonstrated a lower peak E2 level, implantation rate, and clinical pregnancy rate (PR) per initiated cycle (7.7% versus 32.7%). Cyst cycles also demonstrated a higher cancellation rate. Logistic regression modeling, accounting for age, confirmed significantly lower clinical PRs in cycles with a baseline cyst. CONCLUSIONS: Baseline cyst formation after luteal phase GnRH-a administration is both a marker for poor responders and a reliable predictor of poor stimulation and low PRs in a given IVF-ET cycle.

Androgens and therapeutic aspects of antiandrogens in women.

OBJECTIVES: We reviewed the mechanisms of androgen actions and the established and experimental uses of antiandrogens in women. METHODS: Relevant studies were identified through a computerized bibliographic search (MEDLINE) and through manual review of bibliographies in relevant publications. RESULTS: Androgens exert major effects on the functions of gonads, sex organs, and various "nonreproductive" organs and systems, including muscles, liver, skin, nervous system, and the immune system. Most, but not all, of the actions of androgens may be explained by their binding with specific androgen receptors. Antiandrogens prevent androgens from expressing their activity at target cells. They act primarily by binding to androgen receptors and thus preventing activation of receptors by androgens. Steroidal antiandrogens may also exert a wide range of other hormonal and antihormonal effects by interacting with receptors for progesterone, glucocorticoids, and mineralocorticoids. Furthermore, some antiandrogens may decrease the production of androgens by acting at the hypothalamic-pituitary unit and modifying the release of LH, or by directly inhibiting individual enzymes involved in steroidogenesis. Antiandrogens are widely used in the treatment of women with various hyperandrogenic conditions, including polycystic ovary syndrome, idiopathic hirsutism, acne, seborrhea, and hair loss. CONCLUSIONS: Antiandrogens provide a logical and clinically effective pharmacotherapy of hyperandrogenic disorders. However, both steroidal and nonsteroidal antiandrogens may cause significant side effects, largely because of their interactions not only with androgen receptors, but also with other receptors and various enzymatic activities. Difficulties in designing the optimal antiandrogen largely result from the complexities of androgen metabolism and action in various tissues.

Comparative studies of androgen metabolism in theca and granulosa cells of human follicles in vitro.

In eight separate experiments, theca and granulosa were isolated from human follicles (5-25 mm in diameter), and their capacities to metabolize radiolabelled testosterone in 24 hour cultures were assessed. Theca metabolized testosterone primarily to androstenedione, however significant aromatization to estradiol-17 beta and to estrone was also observed. Granulosa metabolized testosterone primarily to estra-diol-17 beta and estrone, while smaller quantities were converted to androstenedione. In seven of these experiments, the intermediate of aromatization, 19-hydroxytestosterone, was identified. In six of these experiments, theca, when compared to granulosa, produced more androstenedione but less estradiol-17 beta and estrone. 5 alpha-Reduced androgens were non-detectable or produced in small quantities. In a single experiment, metabolism of androstenedione was compared to metabolism of testosterone by both theca and granulosa. Theca metabolized androstenedione to testosterone in smaller quantities than testosterone to androstenedione. Granulosa metabolized androstenedione to testosterone in higher quantities than testosterone to androstenedione. Both theca and granulosa aromatized androstenedione more readily than testosterone.

Androgenic modulation of progesterone metabolism by rat granulosa cells in culture.

Effects of androgens on progesterone accumulation, utilization of exogenous progesterone and accumulation of [4-14C]progesterone metabolites by rat granulosa cells in culture were studied. Androgen increased progesterone accumulation in cultures without exogenous progesterone and slowed the overall decline of progesterone concentration in cultures supplemented with exogenous progesterone. Both aromatizable testosterone and nonaromatizable 5 alpha-dihydrotestosterone decreased [4-14C]progesterone utilization by granulosa cells by 12 to 30%. This effect was observed irrespective of whether the cells were continuously exposed to androgens or only pre-exposed. In he same experiments, androgens decreased conversion of radiolabeled progesterone to 20 alpha-hydroxy-4-pregnen-3-one by 11 to 50% and to 5 alpha-pregnane-3 alpha, 20 alpha-diol by 26 to 49%. Accumulation of 3 alpha-hydroxy-5 alpha-pregnan-20-one was not altered in 3 h incubations and was increased by up to 43% in 24 h incubations by androgen treatment. It is suggested that androgens alter progesterone catabolism by granulosa cells by decreasing 20 alpha-hydroxysteroid dehydrogenase activity and that this effect may contribute to overall stimulatory action of androgens on progesterone accumulation.

Steroidogenic capabilities of various compartments of rat ovarian follicles in culture.

The production of progesterone, estrogen and androgen as well as the metabolism of radiolabelled progesterone by various cellular components of rat ovarian follicles were studied. Granulosa (G), theca (T), recombined granulosa plus theca (G+T) and intact follicular wall (FW) of ovaries from immature rats treated with pregnant mare serum gonadotropin (8 IU) were cultured for 24 h in the presence or absence of [4-14C]progesterone. The estrogen and androgen accumulation when calculated per follicle was several fold greater in FW than in G, T, or G+T preparations. The conversion of radiolabelled progesterone to its identified C21 catabolites (20 alpha-hydroxy-4-pregnen-3-one and 3 alpha-hydroxy-5 alpha-pregnan-20-one) was significantly lower in FW than in G+T incubations. Conversely, the metabolism of radiolabelled progesterone to androsterone was several fold greater in FW than in G+T incubations. Addition of hydroxyflutamide to FW incubations significantly decreased estrogen production and increased the conversion of radiolabelled progesterone to androsterone. Estrogen production by follicular wall may be enhanced by androgenic stimulation of aromatase activity as well as by a structure-dependent factor(s) of a yet unknown nature, both of which may decrease progesterone catabolism to biologically inactive progestins while promoting progesterone conversion to androgens and eventually to estrogens.

Changes in magnetic resonance transverse relaxation times of two muscles following standardized exercise.

Magnetic resonance (MR) imaging studies of exercising leg muscles were performed to compare the changes in MR transverse relaxation times (T2) that result from exercise of the anterior tibialis (AT) and extensor digitorum/hallicus longus (E) in the anterior compartment of the lower leg with those T2 changes in the medial and lateral gastrocnemius (G) in the posterior compartment. Spin-echo MR images were obtained at 1.5 Tesla before and during the first 14 min of recovery from dynamic exercise. In order to normalize the exercise, workloads for each subject were set at 25% of the measured maximum voluntary contraction (MVC) of the anterior and posterior compartments. In separate exercise sessions, a nonmagnetic, pneumatic exercise apparatus was employed for either dorsiflexion or plantarflexion against a fixed constant resistance for two different exercise durations (1 min 45 s or 5 min). Transaxial MR images (TR = 1000 ms, TE = 30, 60, 90, 120 ms, 128 x 256 matrix, 1.5 cm slice) were used to calculate T2 values. Although subjects performed approximately 7-fold more work (P < or = 0.001, dorsiflexion vs plantarflexion) during plantarflexion than during dorsiflexion at both exercise duration's, the exercise induced T2, while being greater than those at rest (P < or = 0.001), were not significantly different in the different compartments. We conclude that, when exercised at the same workload (25% of MVC), these two muscles produce T2 changes that are not significantly different from each other.

Diagnosis of endometriosis.

Diagnosis of endometriosis requires careful interpretation of objective surgical and pathologic findings in the context of the patient's clinical presentation. Clinical assessment helps to identify patients at high risk of endometriosis and selects those who warrant further testing. Determination of the serum level of CA-125, and to a lesser extent, other proteins, may be helpful in evaluating selected population at risk and following the course of the disease. Selective use of imaging studies, especially ultrasound and magnetic resonance imaging, may also be helpful. Ultimately, the diagnosis of endometriosis is usually confirmed or refuted by laparoscopy, preferably performed in conjunction with histologic evaluation of excised lesions.

Regression analysis and multivariate analysis.

Proper evaluation of data does not necessarily require the use of advanced statistical methods; however, such advanced tools offer the researcher the freedom to evaluate more complex hypotheses. This overview of regression analysis and multivariate statistics describes general concepts. Basic definitions and conventions are reviewed. The types of regression analysis are then discussed, including simple regression, multiple regression, multivariate multiple regression, and logistic regression. The various steps required to perform these analyses are described, and the advantages and disadvantages of each is detailed.

Differential actions of FSH and androgens on progesterone catabolism by rat granulosa cells.

Rat granulosa cells were preincubated with follicle-stimulating hormone (FSH, 1 micrograms/ml) and/or androgens (testosterone and 5 alpha-dihydrotestosterone, 0.5 microM) and subsequent [4-14C]progesterone metabolism by these cells was studied. Granulosa cells metabolized radiolabeled progesterone to three major products 20 alpha-hydroxy-4-pregnen-3-one, 3 alpha-hydroxy-5 alpha-pregnan-20-one, and 5 alpha-pregnane-3 alpha, 20 alpha-diol. Androgens, but not FSH, decreased overall progesterone utilization. Both FSH and androgens decreased conversion of progesterone to 20 alpha-hydroxy-4-pregnen-3-one. The accumulation of 5 alpha-pregnane-3 alpha, 20 alpha-diol was increased by FSH, decreased by testosterone, and not altered by 5 alpha-dihydrotestosterone. The accumulation of 3 alpha-hydroxy-5 alpha-pregnan-20-one was significantly increased by both FSH and androgens. Present results indicate that FSH as well as androgens modulate progesterone metabolism by rat granulosa cells. FSH appears to increase 5 alpha-reductase activity and/or decrease 20 alpha-hydroxysteroid dehydrogenase activity while androgens decrease only 20 alpha-hydroxysteroid dehydrogenase activity.

Androgenic alteration in pathways of C19-steroid metabolism by cultured rat granulosa cells.

Pretreatment of rat granulosa cells with androgens altered the subsequent metabolism of [4-14C]testosterone in vitro. In cells pretreated with testosterone or 5 alpha-dihydrotestosterone, the accumulation of radiolabeled 5 alpha-androstane-3 alpha, 17 beta-diol decreased by 40% and 36%, respectively, when compared with control, while the levels of androstenedione increased by 64% and 54%, respectively. For comparison, pretreatment with 0.5 microM 17 beta-estradiol failed to affect the level of radioactivity incorporated into all three major metabolites. In other experiments, granulosa cells were incubated in the presence of 0.5 microM [4-14C]dihydrotestosterone. While 5 alpha-androstane-3 alpha, 17 beta-diol was decreased slightly by pretreatment with testosterone or 5 alpha-dihydrotestosterone, radiolabeled androsterone was increased significantly. These data suggest a possible modulatory action of androgens on ovarian 17 beta-hydroxysteroid dehydrogenase and/or 5 alpha-reductase activity.