Trisomic pregnancy and elevated FSH: implications for the oocyte pool hypothesis.

BACKGROUND: Some studies, but not all, support the hypothesis that trisomy frequency is related to the size of the oocyte pool, with the risk increased for women with fewer oocytes (older ovarian age). We tested this hypothesis by comparing hormonal indicators of ovarian age among women who had trisomic pregnancy losses with indicators among women with non-trisomic losses or chromosomally normal births. The three primary indicators of advanced ovarian age were low level of anti-Müllerian hormone (AMH), high level of follicle-stimulating hormone (FSH) and low level of inhibin B. METHODS: The analysis drew on data from two hospital-based case-control studies. Data were analyzed separately and the evidence from the two sites was combined. We compared 159 women with trisomic pregnancy losses to three comparison groups: 60 women with other chromosomally abnormal losses, 79 women with chromosomally normal losses and 344 women with live births (LBs) age-matched to women with losses. We analyzed the hormone measures as continuous and as categorical variables. All analyses adjust for age in single years, day of blood draw, interval in storage and site. RESULTS: AMH and inhibin B did not differ between women with trisomic losses and any of the three comparison groups. Mean ln(FSH) was 0.137 units (95% confidence interval (CI): 0.055, 0.219) higher for trisomy cases compared with LB controls; it was also higher, though not significantly so, for trisomy cases compared with women with other chromosomally abnormal losses or chromosomally normal losses. The adjusted odds ratio in relation to high FSH (≥ 10 mIU/ml) was significantly increased for trisomy cases versus LB controls (adjusted odds ratio (OR): 3.8, 95% CI: 1.6, 8.9). CONCLUSIONS: The association of trisomy with elevated FSH is compatible with the oocyte pool hypothesis, whereas the absence of an association with AMH is not. Alternative interpretations are considered, including the possibility that elevated FSH may disrupt meiotic processes or allow recruitment of abnormal follicles.

Trisomic pregnancy and the oocyte pool.

BACKGROUND: We tested the hypothesis that trisomy risk is increased for women with fewer oocytes (older ovarian age) than other women of the same chronological age. METHODS: Our study compared three indicators of ovarian age-number of antral follicles, level of dimeric inhibin B, level of FSH-among women who had trisomic pregnancy losses (n = 54) with those among women who had other losses (24 with other chromosomally abnormal loses, 21 with chromosomally normal losses) or who had chromosomally normal births (n = 65). RESULTS: Ovarian age indicators did not differ between women with trisomic spontaneous abortions and the three comparison groups. Compared with live birth controls, adjusting for chronological age, we estimate that, on average, among trisomy cases the geometric means of 1 + follicle count, inhibin B and FSH are about 7.5% higher, 16.6% higher and 5.5% lower, respectively, with all 95% confidence intervals including zero. The sample size was sufficient to detect moderate differences (0.52 standard errors of regression) between trisomy cases and live birth controls. CONCLUSIONS: Although our data do not support our hypothesis, they leave open the possibility that changes in follicular development unrelated to the size of the oocyte pool influence abnormal chromosome segregation.

Differential effects of estradiol on the adrenocorticotropin responses to interleukin-6 and interleukin-1 in the monkey.

Endotoxin and the inflammatory cytokines interleukin (IL)-1 and IL-6 are potent activators of the hypothalamic-pituitary-adrenal (HPA) axis. Although estradiol (E(2)) has been shown to enhance the HPA response to certain types of stress, previous studies in the rodent have shown that HPA responses to endotoxin and to IL-1 were enhanced by ovariectomy and attenuated by E(2). The mechanisms underlying these observations are unclear, but there is evidence that E(2) may have direct inhibitory effects on IL-6 synthesis and release. Because endotoxin and IL-1 both stimulate IL-6, it is possible that the E(2)-induced suppression of the HPA response to endotoxin and IL-1 results from decreased IL-6 release. We have therefore examined the ACTH response to IL-6 and IL-1beta in six ovariectomized rhesus monkeys with and without 3 weeks of E(2) replacement. In the first study, plasma ACTH levels peaked at 60 min after iv injection of 6 microg recombinant human IL-6. Both the ACTH response, over time, and the area under the ACTH response curve were significantly higher in the E(2)-treated animals (P < 0.05). The peak ACTH level was 66 +/- 16 pg/ml without E(2) vs. 161 +/- 69 pg/ml with E(2). In the second study, iv infusion of recombinant human IL-1beta (400 ng) produced plasma IL-6 levels comparable with those seen after IL-6 injection in the first study. In the IL-1 study, however, there was a significant attenuation of the ACTH response, over time, in the E(2)-treated animals (P < 0.001); the peak ACTH level was 83 +/- 34 pg/ml vs. 13 +/- 4.4 pg/ml after E(2). The IL-6 response was similarly attenuated (P < 0.001); the peak IL-6 level was 614 +/- 168 pg/ml vs. 277 +/- 53 pg/ml after E(2) treatment. Our results demonstrate that physiological levels of E(2) enhance the ACTH response to IL-6 but attenuate the ACTH response to IL-1. The attenuated ACTH response to IL-1 was accompanied by a blunted IL-6 response. Our results suggest that the blunted HPA response to IL-1 can be explained, at least in part, by E(2)-induced alterations in IL-6 release. It remains to be determined whether E(2) affects other inflammatory mediators that also participate in this process.

Short-term administration of antivascular endothelial growth factor antibody in the late follicular phase delays follicular development in the rhesus monkey.

Indirect evidence in the nonhuman primate and human suggests that angiogenesis and regulators of angiogenesis such as vascular endothelial growth factor (VEGF) may play an active role in cyclic folliculogenesis. Indeed, the follicle selected for maturation and ovulation possesses a denser microvascular network, and VEGF messenger ribonucleic acid and its protein have been identified in granulosa cells of the developing follicle during the mid- and late follicular phases, with a more intense signal in the mature follicle. The objective of this study was to obtain direct evidence in the nonhuman primate for an active role of VEGF in follicular growth and maturation by studying the effect of VEGF-blocking antibodies in this process. After documenting two normal ovulatory cycles, female rhesus monkeys (n = 7) received iv injections of anti-VEGF antibodies (0.5 mg) twice on successive days in the late follicular phase. Three monkeys also received nonspecific goat IgG (0.5 mg) twice on successive days in the late follicular phase. Daily measurements of estradiol, progesterone, LH, and FSH were obtained during the two control cycles, the anti-VEGF treatment and posttreatment cycles, and the IgG treatment cycle. Anti-VEGF antibody administration significantly lengthened the follicular phase in six of seven monkeys to 17.8 +/- 1.7 vs. 10.0 +/- 0.7 and 9.8 +/- 0.6 in control cycles and 10.7 +/- 0.3 days (mean +/- SE) in IgG-treated cycles. The expected late follicular phase rise in estradiol, as documented in the control cycles (day 0, 96.1 +/- 6.0; day 1, 125.5 +/- 20.0; day 2, 165.5 +/- 24.9; day 3, 183.8 +/- 11.0 pg/mL), was interrupted by anti-VEGF antibody treatment (99.3 +/- 5.0, day 0, preinjection control) to 63.3 +/- 12.2 (day 1), 48.5 +/- 8.7 (day 2), and 57.6 +/- 9.0 (day 3). Mean FSH levels were significantly increased by day 2 of anti-VEGF antibody treatment. After a variable delay, estradiol concentrations increased to reach a preovulatory peak in all anti-VEGF-treated animals, followed by ovulation, normal luteal function, and a normal posttreatment cycle. The data clearly demonstrate that short-term inhibition of angiogenesis with an anti-VEGF-blocking antibody during the later growth phase of the dominant follicle interferes with normal follicular development. Persistence of estradiol secretion and delayed resumption of its rise also suggest recovery of the follicle. We conclude that the angiogenic regulator VEGF is a crucial component in the process of follicular growth in the primate.

Reproductive dysfunction in women with epilepsy: antiepileptic drug effects on sex-steroid hormones.

Women with epilepsy are at risk for reproductive health dysfunction. Sex-steroid hormone abnormalities have been reported in women with epilepsy, but it has been difficult to determine whether these abnormalities are due to epilepsy-related hypothalamic-pituitary axis dysfunction, or to pharmacokinetic actions of antiepileptic drugs (AEDs). Sex-steroid hormones were evaluated in 84 reproductive-aged women with epilepsy receiving an AED in monotherapy, and in 20 nonepileptic controls. Estrone, free testosterone, and androstenedione were significantly lower in subjects receiving enzyme-inducing AEDs than in nonepileptic controls. Free testosterone was significantly elevated in subjects receiving valproate compared to nonepileptic controls. Subjects with epilepsy receiving gabapentin or lamotrigine were no different from the nonepileptic controls in any of the endocrine variables. Subjects with epilepsy who are receiving AEDs that alter cytochrome P450 enzymes are at risk for significant abnormalities in sex-steroid hormones. In contrast, subjects receiving AEDs that do not alter cytochrome P450 enzymes show no differences in sex-steroid hormones compared with nonepileptic controls. With new AEDs available that do not alter cytochrome P450 enzymes, physician selection of therapy should consider not only seizure control, but also potential effects on reproductive physiology.

Stimulatory effects of stress on gonadotropin secretion in estrogen-treated women.

Although stress is known to inhibit the hypothalamic-pituitary-gonadal axis, recent studies in the monkey show that, under certain conditions, in the presence of estrogen, stress may actually stimulate LH release. We investigated the effects of a mild inflammatory stress (2.0-3.0 ng/kg endotoxin) on LH release in five postmenopausal women with and without transdermal estradiol (E2, 0.1 mg) replacement. In another five E2-treated women, LH release was studied when the adrenal was stimulated directly by a 3-h ACTH infusion (Cortrosyn, 50 microg/h). Mean E2 levels were less than 12 pg/mL in the unreplaced subjects and were 86 +/- 10 pg/mL and 102 +/- 18 pg/mL in the two groups of E2-replaced subjects. Blood was sampled every 15-20 min for 2 h before and for 7 h after endotoxin or ACTH injection. Mean cortisol and progesterone levels increased in all three groups over time (P < 0.001). In the women without E2 replacement, basal LH was 26.8 +/- 5.3 mIU/mL and did not change significantly, over time, after endotoxin (P = 0.58). In the same women on E2, however, a significant increase in LH occurred after endotoxin (P = 0.02), from a mean hourly baseline of 15.3 +/- 5.4 mIU/mL to a peak of 50.0 +/- 25.2 mIU/mL. During the ACTH infusion, there was a significant stimulation of LH release in the E2-replaced subjects (P < 0.001), from a mean hourly baseline of 13.3 +/- 3.0 mIU/mL to a peak of 44.1 +/- 11.7 mIU/mL. In both groups, this increase occurred 2-4 h after the initial rise in progesterone and persisted to the end. We conclude that, in the presence of sufficient estrogen, activation of the hypothalamic-pituitary-adrenal axis leads to a stimulation of LH release. This is likely related to a rise in adrenal progesterone and its known stimulatory effect on LH release in the presence of E2. These studies provide a potential mechanism in the human by which an acute stress during the follicular phase of the menstrual cycle might lead to a premature LH surge and thereby interfere with follicular maturation and ovulation.

Normal ovulatory women with polycystic ovaries have hyperandrogenic pituitary-ovarian responses to gonadotropin-releasing hormone-agonist testing.

Women with polycystic ovary syndrome (PCOS) have chronic anovulation and hyperandrogenism and frequently have abnormalities in their lipid profiles and insulin/insulin-like growth factor axis that increase their lifetime risk for cardiovascular disease. Normal ovulatory women may have polycystic ovaries on ultrasonography and yet lack the clinical features of PCOS. To further explore whether ovulatory women without clinical/biochemical hyperandrogenism but with polycystic appearing ovaries (ov-PAO) have subclinical features of PCOS, we prospectively characterized 26 ov-PAO women and matched them by age and body mass index to 25 ovulatory women with normal appearing ovaries (ov-NAO) and to 22 women with PCOS. After an overnight fast, all women had baseline endocrine and metabolic assessments. In addition, a subset of each group of women underwent GnRH-agonist (leuprolide acetate 1 mg s.c.) testing, ACTH stimulation, and an insulin tolerance test (ITT). At baseline, ov-PAO and ov-NAO women had similar endocrine profiles (LH, LH:FSH, androstenedione, and DHEAS). Compared with ov-NAO, 31% of ov-PAO women had reduced glucose responses after insulin (K(itt)), suggesting mild insulin resistance, and 35% had high density lipoprotein levels below 35 mg/dL, a level considered to represent significant cardiovascular risk. After GnRH-agonist, ov-PAO women had response patterns in LH, total testosterone, and 17-hydroxyprogesterone (17-OHP) that were intermediate between ov-NAO and women with PCOS. Ovarian responses were above the normal range in 30-40% of women with ov-PAO. In ov-PAO, peak responses of LH after leuprolide correlated with triglyceride levels (P < 0.05) and peak responses of 17-OHP correlated inversely with Kitt values (P < 0.05). No significant differences were noted with ACTH testing. In conclusion, occult biochemical ovarian hyperandrogenism may be uncovered using GnRH-agonist in ovulatory women with ov-PAO, while adrenal responses remain normal. Subtle metabolic abnormalities may also be prevalent.

Endogenous estrogen levels and Alzheimer's disease among postmenopausal women.

BACKGROUND: Although several studies have suggested that hormone replacement therapy lowers the risk of AD among postmenopausal women, few studies have evaluated the relationship of endogenous estrogen levels and AD. The current study investigated whether serum estrone and estradiol levels were related to the presence of AD among postmenopausal women not currently taking hormone replacement therapy. METHODS: Using a case-control design, we examined an ethnically diverse sample of postmenopausal women who met National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria for AD (n = 50) and nondemented controls (n = 93). All women were participants in a study of aging and dementia and were seen consecutively between August 1997 and October 1998. RESULTS: Patients with AD had lower estradiol (F[1,141] = 8.3, p = 0.005) levels than did normal controls. Patients also had lower estrone levels; however, this comparison did not quite meet significance criteria (F[1,141] = 3.6, p = 0.06). Compared to estradiol levels >20 pg/mL, women with AD were four to six times more likely to have levels <20 pg/mL after adjusting for age, years of education, presence of an APOE-epsilon4 allele, ethnicity, and body mass index. There were no significant differences in frequency of AD among women within different quartiles of estrone after adjusting for potential confounds. CONCLUSIONS: The results of this preliminary case-control study suggest that estradiol levels may decline significantly in women in whom AD develops.

Inhibitory effects of endotoxin on LH secretion in the ovariectomized monkey are prevented by naloxone but not by an interleukin-1 receptor antagonist.

Endotoxin (lipopolysaccharides, LPS), the pathogenic moiety of gram-negative bacteria, is a well-known trigger for the central release of cytokines. The objective of this study is to evaluate the effects of systemic endotoxin administration on LH and cortisol secretion in a non-human primate model and to investigate whether these endocrine effects are mediated by centrally released interleukin-1 (IL-1) using the receptor antagonist to IL-1 (IL-1ra). An additional objective is to investigate whether endogenous opioid peptides mediate these endocrine effects of LPS, using the opiate antagonist naloxone. The experiments were performed in long-term-ovariectomized rhesus monkeys. Blood samples for hormone determination were obtained at 15-min intervals for a period of 8 h, which included a 3-hour baseline period. Since the effective central dose of IL-1ra in the monkey was unknown, in the first experiment we tested the potency of several doses of this antagonist in preventing the effects of centrally administered IL-1alpha, a cytokine which is known to inhibit LH and stimulate cortisol release. Rhesus monkeys received a 30-min intracerebroventricular infusion of IL-1alpha (4.2 microg/30 min) alone or together with various doses of IL-1ra (30-180 microg/h i.c.v.). IL-1ra infusion was initiated 1 h before IL-1 and extended over the experimental period. As previously reported, IL-1alpha induced a significant inhibition of LH, to 36.5 +/- 3.3% (mean +/- SE) by 5 h as a percentage from the 3-hour baseline. This inhibitory effect was reversed by cotreatment with the 180 microg/h dose of IL-1ra (to 82.5 +/- 3.8% by 5 h; NS vs. saline) but not with the lower doses. IL-1 stimulated cortisol release to 165.9 +/- 7.7%, but this increase was prevented by IL-1ra (66.6 +/- 8.9%; p < 0.05 vs. IL-1, NS vs. saline). In the second experiment, LPS (50 microg) was administered intravenously, alone or in combination with intracerebroventricular IL-1ra infusion. LPS induced a significant decrease in LH secretion (to 57.1 +/- 5.2%). These effects were not reversed by intracerebroventricular administration of IL-1ra (52.5 +/- 9.6%). Cortisol secretion increased in response to LPS, but this stimulatory effect was not affected by IL-1ra (178.3 +/- 13.4 vs. 166.9 +/- 5.7%). There were no effects of IL-1ra alone. In experiment 3, we investigated whether the opiate antagonist naloxone reverses the endocrine effects of endotoxin. Both LPS (50 microg) and naloxone (5-mg bolus + 5 mg/h) were infused intravenously. Naloxone was effective in preventing the inhibitory effect of LPS on LH (to 124.6 +/- 22.1%, NS vs. saline) but not the increase in cortisol (to 166.7 +/- 16.7%; p < 0.05 vs. saline, NS vs. LPS). Naloxone alone has no significant effect on LH or cortisol secretion. These data demonstrate that, in the ovariectomized monkey, a systemic inflammatory/immune- like stress challenge acutely inhibits tonic LH secretion while concomitantly stimulating cortisol release. Although endotoxin is known to affect central cytokine release, these endocrine effects do not require a mediatory role of central IL-1 in the primate. In contrast, endogenous opioid pathways appear to be involved in this process.

Evidence that insulin and androgens may participate in the regulation of serum leptin levels in women.

OBJECTIVE: Although serum leptin is principally influenced by body mass, to understand the role of insulin and androgens in the regulation of serum leptin in normal weight women. DESIGN: Prospective observational study. SETTING: Academic practice in reproductive endocrinology. PATIENT(S): Twenty-one women with polycystic ovary syndrome (PCOS) of normal body weight, 8 apparently normal women with polycystic-appearing ovaries (PAO), and 21 normal women. INTERVENTION(S): Fasting blood levels of luteinizing hormone, follicle-stimulating hormone, testosterone (T), unbound T, dehydroepiandrosterone sulfate (DHEAS), insulin, insulin growth factor-binding protein-1 (IGFBP-1), and leptin. MAIN OUTCOME MEASURE(S): Comparisons of measured hormones in the different groups and correlative analysis RESULT(S): Women with PCOS had higher levels of serum luteinizing hormone, T, unbound T, DHEAS and insulin, and lower levels of IGFBP-1 compared with the normal controls, but they had similar leptin levels. Normal women with PAO had increased levels of insulin and leptin compared with controls, whereas IGFBP-1 was lower in PAO. In normal weight women with PCOS and PAO, leptin correlated positively with body weight and insulin, and negatively with IGFBP-1 and DHEAS. CONCLUSION(S): In normal weight patients serum leptin levels may be regulated in part by insulin. Androgens, on the other hand, may play a role in suppressing serum leptin.

Intracerebroventricular injection of interleukin-1 stimulates the release of high levels of interleukin-6 and interleukin-1 receptor antagonist into peripheral blood in the primate.

Previous studies in the rodent have shown that the cytokine IL-1 can act within the brain to influence peripheral IL-6 secretion. In order to determine if such an interaction occurs in the primate, we have compared the effects of intracerebroventricular vs. intravenous injection of IL-1beta on the release of IL-6 into the peripheral circulation of the monkey. The effects of i.c.v. IL-1beta on the release of the IL-1 receptor antagonist (IL-1ra) were studied in parallel. For comparison, we have also measured the release of both IL-6 and IL-1ra into lumbar CSF after i.c.v. IL-1beta injection. Ten ovariectomized rhesus monkeys with indwelling lateral ventricular and peripheral venous cannulae were studied. Human rIL-1beta (400 ng) was infused either i.c.v. or i.v. over 30 min and blood samples were collected for IL-6 and IL-1ra measurement by monoclonal human ELISAs. Although both i.c.v. and i.v. IL-1beta stimulated IL-6 and IL-1ra release into peripheral blood, the stimulation was much more profound after i.c.v. injection (p < 0.001). Peak IL-6 levels were 2010 +/- 590 pg/ml after i.c.v. IL-1beta compared to 243 +/- 60 pg/ml after i.v. IL-1beta. Peak IL-1ra levels were 61,310 +/- 16,190 pg/ml after i.c.v. IL-1beta compared to 18,175 +/- 4270 pg/ml after i.v. IL-1beta. There was no significant effect of an i.c.v. saline infusion on peripheral IL-6 or IL-1ra levels. In four animals, lumbar CSF was collected 7 h after i.c.v. IL-1beta injection. The mean concentration of IL-6 in CSF was 103, 570 +/- 13,780 pg/ml after i.c.v. IL-1beta vs. 224 +/- 190 pg/ml after i.c.v. saline injection; IL-1ra was 47,460 +/- 6290 pg/ml vs. 1040 +/- 550 pg/ml. As expected, both i.c.v. and i.v. IL-beta stimulated ACTH and cortisol release; the stimulation was significantly greater after i.c.v. compared to i.v. administration (p < 0.001). Thus, in the monkey, i.c.v. injection of IL-1beta stimulates the release of large amounts of IL-6 and IL-1ra into the CSF and the peripheral circulation. Both IL-6 and IL-1ra were released into the peripheral circulation to a much greater extent after i.c.v. compared to i.v. IL-1beta infusion. These studies provide further support in the primate for a mechanism by which inflammation within the brain could induce a variety of systemic responses.

The contributions of oestrogen and growth factors to increased adrenal androgen secretion in polycystic ovary syndrome.

Adrenal hyperandrogenism is prevalent in many women with polycystic ovary syndrome (PCOS), although the expression of this enhanced secretion may be heterogeneous. Since no single factor acts in isolation, this study was performed to assess the influence of oestradiol (total and unbound), insulin, insulin-like growth factor (IGF)-I, IGF-II and the binding proteins IGFBP-I, and IGFBP-3, on basal and adrenocorticotrophic hormone (ACTH) stimulated adrenal androgen secretion in 25 women with PCOS and 10 matched ovulatory controls. Women with PCOS exhibited elevations of all androgens as well as unbound oestradiol, insulin and non-IGFBP-1 bound IGF-I. Positive correlations were noted between oestrogen and basal and ACTH stimulated delta 5 adrenal androgens. Serum IGF-I was only correlated with basal dehydroepiandrosterone sulphate (DHEA-S), while insulin exhibited a strong correlation with the delta 4 pathway and androstenedione formation in particular. This correlation was also confirmed by dividing the PCOS group into those women with and without hyperinsulinaemia. The activity of 17,20 lyase favouring androstenedione was increased in the hyperinsulinaemic women. By multivariate analyses, body mass index did not influence these findings. Although there are inherent difficulties in making major conclusions based on correlative analyses, it is suggested that oestrogen may have a greater influence on enhancing delta 5 adrenal androgen secretion, and insulin a greater effect on the delta 4 pathway. In turn, the relative importance of these influences may contribute to the heterogeneous nature of adrenal hyperandrogenism in PCOS.

Stress and the menstrual cycle: short- and long-term response to a five-day endotoxin challenge during the luteal phase in the rhesus monkey.

Previously, we reported that in the rhesus monkey a 5-day inflammatory-like stress during the early-mid follicular phase acutely stimulates the hypothalamic-pituitary-adrenal axis and exerts effects on the hypothalamic-pituitary-gonadal axis, delays folliculogenesis and in some animals decreases luteal function in the post-treatment cycle. Because the endocrine environment at the time of the stress may influence the response to the stress, we now investigate the acute and long-term responses to a similar stress challenge during the luteal phase of the menstrual cycle, at a time of progesterone dominance. Nine monkeys with normal cycles were injected with endotoxin (lipopolysaccharide; LPS, 150 microg i.v.) twice a day for 5 days starting on days 4-8 after the LH peak. Blood samples were taken at hour 3 and hour 8 after each morning LPS injection to monitor the acute gonadotropin and cortisol responses. To verify cyclicity, menses were checked every day, and daily blood samples were taken for estradiol and progesterone measurement. Two control cycles, the LPS treatment cycle, and two post-treatment cycles were documented. Endotoxin activated the adrenal axis: mean (+/-SE) cortisol secretion was significantly increased at hour 3 after the first morning LPS injection (74.1 +/- 4.9 vs. 24.1 +/- 1.8 microg/dL in the control; P < 0.05) and remained elevated at hour 8. This response decreased progressively with time: on day 5 of LPS treatment, the cortisol level was still significantly higher than control at hour 3 (38.5 +/- 5.0 microg/dL; P < 0.05) but had returned to the control concentration by hour 8 (days 3-5 of LPS). Mean integrated progesterone through the luteal phase of the LPS treatment cycle was significantly decreased (33.5 +/- 3.3 ng/ml vs. 48.9 +/- 3.7 and 54.0 +/- 4.9 in the two control cycles; P < 0.05), but luteal phase length remained unchanged. When compared with control levels on the same day of the luteal phase, about one third of LH and FSH values were lower than one SD below mean control levels. LPS administration had no effect on the two post-treatment cycles, except that integrated luteal progesterone in 3 out of 9 monkeys was still reduced in post-treatment cycle 1. There were no differences in follicular phase length and preovulatory estradiol peaks between control cycles and post-treatment cycles. When compared with our previous study, the results illustrate specific responses to stress at different phases of the menstrual cycle and support the notion that a moderate short-term inflammatory-like stress episode has the potential to subtly alter critical aspects of cyclicity.

The utility of serum progesterone and inhibin A for monitoring natural-cycle IVF-ET.

PURPOSE: Our purpose was to assess the value of monitoring serum P and inhibin A to determine how values might improve the clinical monitoring of natural cycle in vitro fertilization (IVF)-embryo transfer (ET) patients. METHODS: All patients (n = 26) who underwent natural-cycle IVF-ET (n = 35) were analyzed. Groups were evaluated according to patients who had a spontaneous luteinizing hormone (LH) surge (group I) and women receiving human chorionic gonadotropin (hCG) who underwent subsequent oocyte aspiration (group II). Group II was further evaluated according to women who did (n = 10) and did not (n = 7) have an ET. All cycles were evaluated with serial transvaginal ultrasonography and serum estradiol, progesterone, and inhibin A. When follicle maturity was achieved, hCG, 10,000 IU, was administered intramuscularly if a LH surge was not detected. Transvaginal ultrasound-guided aspiration was performed 34-36 hr after hCG administration followed by a 48-hr transcervical ET. RESULTS: No differences were seen in cycles the day prior to (d-1) and the day of a spontaneous LH surge, (n = 18) or hCG (d-0)(n = 17) in group I or group II with respect to lead follicular diameter (d-1, 15.3 +/- 0.6 vs. 14.2 +/- 0.9 mm; d-0, 17.4 +/- 0.8 vs. 17.8 +/- 0.6 mm) and serum estradiol (d-1, 148 +/- 15 vs. 150 +/- 15 pg/ml; d-0, 218 +/- 15 vs. 199 +/- 16 pg/ml), respectively. However, serum progesterone was significantly elevated in group I compared with group II on d-1 (0.82 +/- 0.6 vs. 0.48 +/- 0.04 ng/ml; P < 0.05) and d-0 (1.1 +/- 0.12 vs. 0.63 +/- 0.08 ng/ml; P < 0.05). Inhibin A was significantly greater on d-1 in group I (24 +/- 2.5 vs. 15 +/- 2.2 pg/ml; P < 0.05). In group II, cycles that resulted in an ET (n = 10) compared with group II cycles that did not (n = 7) revealed a significant difference in serum progesterone (0.51 +/- 0.05 vs. 0.7 +/- 0.07 ng/ml; P < 0.05) and inhibin A (15 +/- 2.5 vs. 37.3 +/- 5 pg/ml; P < 0.05) the day of hCG. CONCLUSIONS: The possible application of serum progesterone and inhibin A in managing natural-cycle IVF-ET is suggested. These assays may predict women who should be set up for egg retrieval, while cancelling others in spite of the absence of an LH surge.

Stress and the menstrual cycle: relevance of cycle quality in the short- and long-term response to a 5-day endotoxin challenge during the follicular phase in the rhesus monkey.

The notion that stress activates central and peripheral pathways to inhibit the menstrual cycle is well accepted, but the initial processes through which this occurs have not been investigated. This study uses a relevant nonhuman primate model to document the cyclic endocrine effects imposed by a moderate short-term stress episode in the follicular phase. The stress paradigm is a 5-day inflammatory/immune-like challenge produced by the administration of bacterial endotoxin [lipopolysaccharide (LPS)], which, through the release of endogenous cytokines and other mediators, induces a physiopathological response similar to a bacterial infection. LPS was administered iv twice daily for 5 days starting on days 2-8 of the follicular phase. The stress challenge resulted in a significant lengthening of the follicular phase in all monkeys. Two distinct groups were observed. In group 1 (n = 5), the mean (+/- SE) length of the follicular phase in the LPS-treated cycle was significantly increased, from 10.2 +/- 0.2 in control cycle 2 to 30.8 +/- 4.3 days (except in one monkey that had a 4-month amenorrheic interval). In group 2 (n = 5), the length of the follicular phase significantly increased but not to exceed the duration of the LPS treatment (9.7 +/- 1.1 vs. 13.6 +/- 1.2). Estradiol concentrations decreased significantly after LPS in group 1 (34.8 +/- 5.5 vs. 16.2 +/- 6.5 pg/mL) and remained suppressed after the challenge. In group 2, estradiol levels remained stationary throughout the 5-day LPS treatment (26.0 +/- 6.5 vs. 25.6 +/- 3.9). Compared with control values at a similar stage of the follicular phase, most LH and FSH values during LPS treatment were higher than controls. Estradiol and gonadotropin surges were delayed by LPS treatment for a varying length of time according to each grp. Significant differences in integrated luteal progesterone concentrations characterized control cycles of groups 1 and 2 (group 1: 36.5 +/- 1.5, group 2: 47.5 +/- 2.6). In group 1, there were no further effects of LPS on luteal progesterone during the treatment and two post-LPS cycles. In contrast, in group 2, integrated luteal progesterone concentrations were significantly decreased in post-LPS cycle 1 (to 36.0 +/- 4.4). Cortisol significantly increased at hour 3 after each morning LPS injection but the amplitude of the response decreased over the 5-day period. Progesterone increased significantly by hour 3 after the first LPS injection but remained unchanged after subsequent LPS administration. Our data demonstrate that a 5-day inflammatory-like episode during the follicular phase can delay folliculogenesis and that damage to this process is intensified in individuals who already demonstrate a subtle cyclic degradation, in the form of decreased progesterone secretion in the luteal phases preceding the stress episode. Long-term endocrine effects, in the form of decreased luteal secretory activity in the first poststress cycle, are observed in normally cycling individuals, suggesting that inadequacy of the luteal phase may represent the first stage in the damage that a stress episode can inflict upon the normal menstrual cycle.

Tonic support of luteinizing hormone secretion by adrenal progesterone in the ovariectomized monkey replaced with midfollicular phase levels of estradiol.

Although it is known that progesterone facilitates the estradiol-induced gonadotropin surge at midcycle, its effect on LH secretion at other times of the follicular phase remains to be investigated. In this study, we investigate the role of progesterone on tonic LH secretion in the ovariectomized primate replaced with estradiol at levels representative of the follicular phase. The experiments were performed in nine ovariectomized rhesus monkeys, either unreplaced with estradiol or after a 5-day estradiol therapy to mimic early follicular (10-36 pg/mL; low dose) and midfollicular (medium dose; 40-75 pg/mL) concentrations. We used two antiprogesterone compounds, RU-486 (5 mg) and ORG-31806 (1 mg), to antagonize endogenous progesterone activity and studied their acute effects on LH secretion in each group. LH concentrations were measured at 15-min intervals for a 3-h baseline period and during a 5-h period after antagonist administration. LH concentrations remained unchanged after either antiprogesterone compound or diluent (ethanol) administration in the estrogen-unreplaced monkeys or after low dose estradiol replacement. However, both antiprogesterone compounds significantly decreased LH secretion in monkeys pretreated with the medium dose of estradiol; by 5 h, the mean (+/-SE) areas under the LH curve were 54.8 +/- 4.1% and 64.0 +/- 4.2% after RU-486 and ORG-31806, respectively (P < 0.05 vs. unreplaced and low dose estrogen-replaced groups). To exclude the possibility that the LH response reflects an agonist action of the progesterone antagonist, LH responses to progesterone infusions (at three doses to reproduce preovulatory, luteal, and pharmacological levels) were also examined in monkeys pretreated with midfollicular levels of estradiol. In none of these was there a decrease in LH; rather, progesterone infusions resulted in an increase in LH secretion in all three groups (to 115-194% of baseline in seven of eight monkeys). Finally, we determined that at the dose used in our protocol, neither of the two progesterone antagonists was able to prevent dexamethasone-induced cortisol suppression, thus excluding the possibility that results after progesterone antagonist administration may reflect a putative antiglucocorticoid activity of these compounds. When the doses of the antiprogesterone compounds were increased 6 times, only RU-486 counteracted the effect of dexamethasone on cortisol. In summary, our data indicate support by progesterone of tonic LH secretion in the nonhuman primate under estrogenic conditions similar to the midfollicular phase of the menstrual cycle. Significantly, because the experiments were performed in ovariectomized monkeys, and endogenous progesterone was most probably of adrenal origin, the data also demonstrate a role of the hypothalamo-pituitary-adrenal axis in support of gonadotropin secretion.

Stress-related disturbances of the menstrual cycle.

Stress is a common cause of hypothalamic amenorrhoea. In our laboratory, we have studied the effects of an inflammatory-like stress on gonadotropin secretion and on the menstrual cycle in a nonhuman primate model. In this short review, we summarize some of our findings regarding the mechanisms whereby stress induces disturbances of reproductive function. Our data indicate that the hypothalamic-pituitary-adrenal axis, through the release of corticotropin-releasing hormone and vasopressin, plays a mediatory role. One type of action is exerted through a central process resulting in the inhibition of the gonadotropin-releasing hormone pulse generator. The other type is mediated by a peripheral pathway stimulatory to gonadotropin secretion. Activation of one or the other pathway is determined by the ovarian endocrine milieu. Both actions presumably result in deleterious effects on the menstrual cycle.

Intracerebroventricular injection of interleukin-1 suppresses peripheral lymphocyte function in the primate.

The cytokine interleukin-1 (IL-1) can act within the brain to induce peripheral endocrine and immune effects. In the rodent intracerebroventricular (i.c.v.) injection of IL-1 activates the hypothalamic-pituitary-adrenal axis and suppresses peripheral immune function by a CRH-dependent mechanism. It is unknown if IL-1 can similarly act within the brain to cause peripheral immunosuppression in the primate and to what extent this could be attributed to the IL-1-induced increase in ACTH and cortisol levels. In this study we have characterized the pituitary-adrenal and peripheral lymphocyte responses to IL-1 alpha (4.2 micrograms) infused over 30 min into the lateral ventricle of ovariectomized monkeys (n = 5) as compared with responses to an intravenous (i.v.) ACTH infusion (1 microgram/h for 7 h; n = 4). Four serial blood samples were obtained for ACTH and cortisol determination and for lymphocyte isolation during a 1-hour baseline and for 7 h after IL-1 or ACTH. Lymphocyte proliferation was measured by 3H-thymidine uptake in response to stimulation with phytohemagglutinin. In all 5 animals, IL-1 alpha caused rapid and profound suppression of lymphocyte mitogen responsiveness for 7 h. Baseline lymphocyte proliferation was 51,800 +/- 9,780 cpm and suppressed to a nadir of 4.5% with a mean of 23% baseline over 7 h (p < 0.001). Mean ACTH and cortisol levels increased from 33 +/- (SEM) 4.6 pg/ml and 43 +/- 4.0 micrograms/dl, respectively, during the control period to 90 +/- 14 pg/ml and 56 +/- 2.6 micrograms/dl, respectively, after IL-1 (p < 0.01). Before i.v. ACTH, baseline lymphocyte proliferation was 49,400 +/- 2,820 cpm, and suppressed to a mean of 64% of baseline during ACTH infusion (p < 0.05). Mean ACTH and cortisol levels increased from 48 +/- 5.0 pg/ml and 43 +/- 2.0 micrograms/dl, respectively, to 170 +/- 34 pg/ml and 66 +/- 2.3 micrograms/dl, respectively, during the ACTH infusion (p < 0.01). Lymphocyte suppression after i.c.v. IL-1 was much more profound than after i.v. ACTH (p < 0.01); the area under the IL-1 response curve was 37% of the area under the ACTH response curve. These studies demonstrate for the first time in the primate that centrally injected IL-1 has a profound suppressive effect on lymphocyte function. They also show for the first time in any species that there appears to be a significant immunosuppressive message produced by i.c.v. IL-1 that is not accounted for by the associated increases in ACTH and cortisol.