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Query: UMLS:C0003128 (anovulation)
 1,718 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The following experiments were performed: (i) concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH) and prolactin in plasma were measured at 2, 5, 8, 10 and 15 days in female Wistar rats treated on the first day of life with 100 micrograms oestradiol benzoate or vehicle; (ii) females injected on day 1 with 100 micrograms of oestradiol benzoate or 1 mg of testosterone propionate and from day 1 to day 10 or 15 with FSH and LH were killed on day 90; (iii) females injected from day 1 to day 10 or 15 with prolactin or vehicle were killed on day 90; (iv) females injected on day 1 with oestradiol benzoate and from day 1 to day 15 with a luteinizing-hormone-releasing hormone (LHRH) agonist were killed on day 90; (v) groups of females injected on days 1, 4, 7, 10, 13 and 16 with an LHRH antagonist were killed on day 90. Onset of puberty, vaginal cycles, organ weights and hormonal plasma concentrations were measured. Females treated on the first day of life with 100 micrograms oestradiol showed inhibition of gonadotrophin secretion and stimulation of prolactin secretion during the neonatal period. Females injected on the first day of life with oestradiol benzoate or testosterone propionate showed, in adulthood, anovulation, ovarian atrophy, reduced FSH plasma concentrations, increased prolactin plasma concentrations and reduced pituitary prolactin content.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Changes in pituitary secretion during the early postnatal period and anovulatory syndrome induced by neonatal oestrogen or androgen in rats. 846 3

Ovulation induction is the most common medical intervention for the treatment of infertility. Clomifene is generally the first treatment choice for patients with amenorrhoea, unless there is profound hypothalamic deficiency. When clomifene fails to induce ovulation, menotropins (human menopausal gonadotrophin) or gonadotrophin-releasing hormone (GnRH) are effective, most notably in WHO group 1. In this condition associated with low estrogen and gonadotrophin levels, the aggregate of reported pregnancy rates is 25% per cycle. In hyperprolactinaemic anovulation bromocriptine reduces prolactin levels and thereby restores normal cyclicity. In all of the above conditions, the pharmacological agent addresses a specific defect in an explicit manner. WHO group 2 ovulatory disorders arise from hyperandrogenicity and other conditions that respond less predictably to gonadotrophin therapy. In women with WHO group 2 disorders, the aggregate of reported pregnancy rates is 8%. Ovulation induction is also used in ovulatory infertile women to generate multiple follicles and increase the likelihood of fertilisation. The aggregate of pregnancy rates in clomifene trials was 7% per cycle, and 6% in gonadotrophin trials. Gonadotrophin therapy is more effective, however, in association with assisted reproduction techniques. The contrasting treatment success in discrete disorders (25% per cycle) and heterogeneous disorders such as WHO group 2 and persistent infertility (6 to 8% per cycle) underlines the need for research to discover specific causal mechanisms and identify explicit new pharmacological interventions.
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PMID:Pharmacological interventions for the induction of ovulation. 852 70

A partly synchronized pulsatile secretion of luteinizing hormone (LH) and prolactin has previously been suggested as an indication of the coupling of the respective pulse generators under certain conditions. In women with hyperandrogenemic chronic anovulation, episodic LH secretion is disturbed. It was, therefore, the aim of the present study to evaluate possible changes in episodic prolactin secretion pattern and in LH/prolactin co-pulsatility, and to relate the results to the accelerated LH pulse frequencies often seen in patients with hyperandrogenemic chronic anovulation. Blood samples of 32 patients with hyperandrogenemia were taken at 10-min intervals between 10.00 and 20.00. Nine regularly cycling women with normal hormone levels served as controls. In the women with hyperandrogenemia, despite an average 41% rise of LH pulse frequency, prolactin pulse frequency decreased slightly by 14% as compared to controls; no correlation between the two parameters was found (r = 0.162). The number of coincident LH and prolactin pulses increased continuously with accelerating LH frequency. The best fitting function was a hyperbola which was limited by the maximal observed prolactin frequency. As a consequence, the fraction of LH pulses that were co-secreted with prolactin episodes decreased with higher LH pulse frequencies, while the fraction of prolactin pulses concomitant with LH pulses increased. Our data provide evidence that in women with hyperandrogenemic chronic anovulation a pathological LH pulse frequency is no longer coupled with pulsatile prolactin secretion, suggesting an isolated alteration of the central neuronal control mechanism for LH secretion.
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PMID:Partial uncoupling of luteinizing hormone and prolactin pulse coincidence in hyperandrogenemic women. 854 Feb 94

To determine how continued presence of a calf affected duration of postpartum anovulation, 23 udder-intact cows and their calves were assigned to three treatments on d 4 to 9 postpartum (experimental d 0). The treatments were 1) calf present with unlimited contact with its dam (n = 8), 2) calf restricted to noninguinal contact with its dam (n = 8), and 3) calf weaned from its dam (n = 7). Calves in the calf-present and calf-restricted treatments were weaned after 5 wk. Based on daily measurements of blood progesterone, days to first ovulation after onset of treatments were 35.4 +/- 2.2, 22.5 +/- 2.2, and 14.3 +/- 2.2 for the calf-present, calf-restricted, and calf-weaned treatments, respectively; each one differed (P < .01) from the others. Mean concentrations of LH were greater (P < .05) in the calf-restricted treatment and tended (P = .13) to be greater in the calf-weaned treatment than in the calf-present treatment on d 7 after the onset of treatments. On d 7 and 21, calves in the calf-present and calf-restricted (calves could not suckle) treatments were returned to their dams after overnight separation. Blood samples were collected to assess changes in cortisol, ACTH, prolactin, and oxytocin. No treatment effects were detected on d 7, but on d 21, the calf-present and calf-restricted cows had a greater (P < .05) increase in cortisol after calf return than the calf-weaned cows (calves were not returned), whereas prolactin was increased (P < .05) after calf return in the calf-present cows only. We conclude that calf presence is associated with an increase in cortisol and calf presence without suckling is one factor that delays the onset of first postpartum ovulation in beef cows.
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PMID:Restricting calf presence without suckling compared with weaning prolongs postpartum anovulation in beef cattle. 877

Lactational anovulation is an important factor in determining birth spacing in women living in developing countries. Therefore, a more comprehensive understanding of the mechanisms involved in the relationships among lactation, nutrition and ovulation is important. This study was designed using the food-restricted, lactating rat to examine whether endogenous opioids might be involved in depressing gonadotropin release. Females were mated after 65 d of age and, beginning on d 42 of life, offered food in unrestricted amounts (control) or were food restricted to 50% of what the controls consumed. On d 15 of lactation, dams were injected with either naloxone hydrochloride (3 mg/kg body weight) or saline and killed 0, 15, 30 or 60 min later. Plasma was analyzed for luteinizing hormone, follicle-stimulating hormone and prolactin. Food restriction decreased plasma concentrations of luteinizing hormone and follicle-stimulating hormone (P < 0.005). Naloxone administration marginally influenced follicle stimulating hormone (P < 0.1), but not luteinizing hormone concentration regardless of diet group. The interaction among diet group, drug group and time of killing was significant for plasma prolactin concentration (P < 0.05). Food restriction lowered prolactin concentrations, but this effect was diminished with increasing time after injection of naloxone. Furthermore, the magnitude of the effect of food restriction was lessened and even reversed with treatment of naloxone. These results indicate that endogenous opioids are not the primary mechanism suppressing luteinizing hormone release in food-restricted lactating rats.
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PMID:Naloxone administration does not relieve the inhibition of gonadotropin release in food-restricted, lactating rats. 881 99

An accurate, efficient diagnosis of disorders responsible for abnormal uterine bleeding depends on a systematic consideration of all the possible causes. Careful history and physical and pelvic examinations provide the framework for evaluation. Many adjunctive diagnostic aids can be used to evaluate women with abnormal uterine bleeding. These tests include complete blood cell count, pregnancy test, hormone levels (estradiol, progesterone, follicle-stimulating hormone, luteinizing hormone, prolactin, testosterone, dehydroepiandrosterone sulfate), thyroid function tests, liver function tests, and coagulation profile. The need for these tests are individualized and based primarily on the patient's presentation. In women of reproductive age a complication of pregnancy should always be ruled out. Ectopic pregnancies can be life threatening. The prognosis in women with trophoblastic disease can be altered by a delay in establishing the correct diagnosis. Ultrasonographic studies, particularly transvaginal ultrasonography and hysteroscopy, have played an increasing role in the evaluation of patients with abnormal uterine bleeding over the past decade, especially for cases of intrauterine space-occupying lesions, including endometrial polyps, submucosal myomas, and retained placental fragments. Suspicion of reproductive tract malignancies is heightened in patients > 35 years old, those with a history of oligoovulation or anovulation suggestive of long-term unopposed estrogen exposure, those who are obese, and those who do not respond to first-line medical management. Diagnostic techniques available for the evaluation of these cases include endometrial biopsy, dilatation and curettage, transvaginal ultrasonography, and hysteroscopy. These procedures not only allow accurate diagnosis but may permit immediate therapeutic measures to be taken when organic causes are discovered. In summary, the key to the evaluation of abnormal uterine bleeding is a through history and physical and pelvic examinations governed by the differential diagnosis of excessive uterine bleeding and the selected use of adjunctive diagnostic tests and procedures only when absolutely necessary.
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PMID:Evaluation of patients with abnormal uterine bleeding. 882 62

Anovulation condition (estrogen deficiency due to high prolactin level) is linked with premature loss of bone mass. Bone mineral density was measured in the femur neck and the lumbar spine (L2-L4) with DEXA and the bone density was given by Z-score, which makes comparison to adult women's bone mass (normal reference). The examinations were carried out in two different groups. Bone mineral density was measured in the first group in 14 cases with hyperprolactinemic anovulation (aged 28 to 36 years). The average value of Z-score was -1.148 +/- 0.68. In the second group 39 patients (51.9 +/- 2.3 years) took part in the investigation within one year after menopause and the measured Z-score was less than -1.0 (-1.98 +/- 0.4). In the control group there were 40 postmenopausal patients (52.2 +/- 2.4 years) and their Z-score was more than -1.0 (-0.21 +/- 0.14). Prolactin value was 416 +/- 98 mU/l in the investigated group, while in the control group it was 238 +/- 76 mU/l (p < or = 0.05). Our results suggest that continuation of the antiprolactinemic (bromocryptine) treatment following completion of child-bearing appears to be indicated in premenopausal women with increased levels of serum prolactin. During the perimenopause endangered group, whose risk is increasing for postmenopausal osteoporosis, can be stated by determining prolactin level.
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PMID:[The value of plasma prolactin level determination in the diagnosis of postmenopausal osteoporosis]. 906 19

We used mifepristone (M) to evaluate the role of progesterone in maintaining pseudopregnancy. Cycling rats were made pseudopregnant (psp) by cervico-vaginal stimulation (CVS) on the day of estrus (day 0) and received 10 mg/kg M or vehicle (control groups) on day 3. Blood samples were taken at 06.00 h on days 4, 6 or 7 or at 18.00 h on days 3, 4, 6 or 10. M induced proestrus 2 days later (day 5), estrus on day 6, and a second prolonged diestrus afterwards. Prolactin and progesterone levels were similar in the control and M treated groups excepting on day 6, when both were reduced in the M-treated animals, and these rats were in estrus, suggesting a temporary impairment of luteal function. To demonstrate activated corpora lutea the endometrium was scratched on the fourth day of the first or second diestrus in additional control and M-treated groups. The deciduomal response was seen in the control and M groups after scratching the endometrium on day 4 of the first or second diestrus, respectively, but M blocked the deciduomal response in the first diestrus. Ovulation was confirmed by finding that 66.7% of the M-treated rats showed ova in the Fallopian tubes on the M-induced estrus and 4 out of 10 of the M rats placed with males on the M-induced proestrus showed spermatozoa in the vaginal smears. Half of these became pregnant, delivering 2 pups each. The results show that M can induce ovulation in psp rats, demonstrating that the anovulation observed after CVS is dependent on progesterone, yet luteal function persists after M in pseudopregnancy. Progesterone may act either by suppressing LH secretion or by permitting prolactin secretion, or both. Moreover, progesterone is required to maintain endometrial responsiveness.
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PMID:A single dose of mifepristone induces ovulation in pseudopregnant rats. 932 31

The relative roles of infant suckling and of maternal prolactin (PRL) secretion in lactational anovulation were studied in ovary-intact and ovariectomized rhesus monkeys nursing young that had been removed from their natural mothers. Hypothalamic gonadotropin-releasing hormone (GnRH) pulse generator activity was monitored electrophysiologically in freely behaving animals by radiotelemetry. Serum luteinizing hormone, PRL, estradiol, and progesterone were also measured. Suckling inhibited GnRH pulse generator activity and ovarian cyclicity in all ovary-intact females but had no such effect on the pulse generator in long-term ovariectomized animals. When PRL secretion was suppressed by daily bromocriptine administration, GnRH pulse generator activity remained significantly inhibited and ovulation was prevented in four monkeys (6 trials), whereas in two females (6 trials) a rapid increase in pulse generator frequency and the resumption of ovarian cyclicity were observed although suckling activity was maintained. One monkey displayed both response types. Although these results indicate that suckling per se is able to restrain GnRH pulse generator activity in the absence of PRL, they also suggest that the relative importance of these determinants is variable depending on factors that remain to be determined. The present study also confirms the permissive role of the ovary in the lactational suppression of GnRH pulse generator activity.
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PMID:On the mechanism of lactational anovulation in the rhesus monkey. 957 28

Androgenic disorders are those conditions in women characterized by excessive androgen action. They are the most common endocrinopathy of women, affecting from 10% to 20%. Signs are: persistent acne, hirsutism and androgenic alopecia, which is the female equivalent of male pattern baldness. A subgroup, those traditionally labeled as having polycystic ovary syndrome (PCOS), additionally have anovulation, as well as menstrual abnormalities and, often, obesity. Although women with androgenic disorders usually present themselves for help with the skin or menstrual changes, there are other important implications regarding their health. Women with PCOS have varying degrees of insulin resistance, and an increased incidence of Type II diabetes mellitus, as well as unfavorable lipid patterns. The presence of these risk factors is suggested by upper segment obesity, darkening of the skin, and the other skin changes that make up acanthosis nigricans. Diagnosis involves measurement of circulating androgens (of which free testosterone is most important), together with prolactin and FSH when menstrual dysfunction is present. Many women with androgenic skin changes have normal serum androgen levels, suggesting increased end organ sensitivity to androgens. Others have hyperandrogenism (of ovarian or adrenal origin). Treatment is usually successful in controlling acne, reducing hirsutism and stabilizing, or partially reversing, androgenic alopecia. Pharmacological approaches involve suppressing androgen levels, for example, the use of an appropriate oral contraceptive, or antagonizing androgen action with several medications that have this activity. Unfortunately, most women with androgenic disorders are frustrated in their efforts to obtain medical help. Understanding androgenic disorders will enable the physician to significantly help the majority of women with these conditions.
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PMID:Androgens and women's health. 960 8


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