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

Plasma concentrations of LH, FSH, prolactin, oestradiol-17 beta and progesterone were determined in 18 multiparous sows at 4-h intervals for 15-18 days around weaning at 3 or 5 weeks post partum. Sampling at 10-min intervals for 6 h occurred every 2 days throughout the same period. Shortening lactation significantly reduced the preovulatory LH surge and altered the pattern of FSH release. However, there was no significant effect on ovulation rate or interval from weaning to oestrus between groups. Weaning was consistently associated with a significant rise in basal LH concentrations whilst FSH secretion remained unaffected. Lactation length did not appear to affect the characteristics of episodic LH secretion before weaning, nor were any consistent changes in LH secretion apparent until the preovulatory rise in LH. Plasma prolactin values declined rapidly at weaning and remained low thereafter. These results indicate that the 'trigger' controlling the return to cyclic ovarian activity after weaning in the pig is complex, but it is suggested that lactational anoestrus and anovulation result primarily from a lack of LH stimulation to the ovary.
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PMID:Endocrine changes in sows weaned at two stages of lactation. 640 11

In order to clarify the mechanism of hyperprolactinaemic anovulation, the medial basal hypothalamic (MBH) catecholamine (CA) turnover and LRH concentration, and the serum levels and pituitary contents of gonadotrophins and prolactin (Prl) in hyperprolactinaemic female rats were examined. Hyperprolactinaemia (HPrl) was produced by oral administration of sulpiride for 10 consecutive days; each measurement made on the sulpiride-treated rats was compared with that of control dioestrus rats. Prl, LH, FSH and LRH were determined by radioimmunoassay; CA turnover, as assessed by the accumulation of CA following monoamine oxidase inhibition, was assayed by high performance liquid chromatography with electrochemical detection. Sulpiride treatment induced (1) an increase in the serum Prl and a decrease in the serum LH, (2) an increase in the pituitary FSH and LH contents, (3) an increase in the MBH LRH concentration, and (4) an increase in the MBH dopamine (DA) turnover. These results suggest that HPrl may induce anovulation by impaired LH secretion which was caused by the suppression of LRH release due to an increase in DA turnover in the MBH.
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PMID:Effect of sulpiride-induced hyperprolactinaemia on catecholamine turnover and LRH concentration in the medial basal hypothalamus of rats. 640 70

Overall, significantly more antral follicles greater than or equal to 1 mm diameter were present in Romney ewes during anoestrus than in the breeding season (anoestrus, 35 +/- 3 (mean +/- s.e.m.) follicles per ewe, 23 sheep; Day 9-10 of oestrous cycle, 24 +/- 1 follicles per ewe, 22 sheep; P less than 0.01), although the mean numbers of preovulatory-sized follicles (greater than or equal to 5 mm diam.) were similar (anoestrus, 1.3 +/- 0.2 per ewe; oestrous cycle, 1.0 +/- 0.1 per ewe). The ability of ovarian follicles to synthesize oestradiol did not differ between anoestrus and the breeding season as assessed from the levels of extant aromatase enzyme activity in granulosa cells and steroid concentrations in follicular fluid. Although the mean plasma concentration of LH did not differ between anoestrus and the luteal phase of the breeding season, the pattern of LH secretion differed markedly; on Day 9-10 of the oestrous cycle there were significantly more (P less than 0.001) high-amplitude LH peaks (i.e. greater than or equal to 1 ng/ml) in plasma and significantly fewer (P less than 0.001) low amplitude peaks (less than 1 ng/ml) than in anoestrous ewes. Moreover, the mean concentrations of FSH and prolactin were significantly lower during the luteal phase of the cycle than during anoestrus (FSH, P less than 0.05, prolactin, P less than 0.001). It is concluded that, in Romney ewes, the levels of antral follicular activity change throughout the year in synchrony with the circannual patterns of prolactin and day-length. Also, these data support the notion that anovulation during seasonal anoestrus is due to a reduced frequency of high-amplitude LH discharges from the pituitary gland.
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PMID:Changes in gonadotrophin secretion and ovarian antral follicular activity in seasonally breeding sheep throughout the year. 642 May 56

The clinical use of bromocriptine was investigated in 50 hyper- and 30 normoprolactinaemic women attending an infertility clinic and presenting with anovulatory cycles, oligomenorrhoea or amenorrhoea and the complaint that they had failed to become pregnant. The results confirmed that bromocriptine is effective in the treatment of hyperprolactinaemic states. Bromocriptine supresses prolactin secretion irrespective of the underlying pathologic process. Hyperprolactinaemia in humans is frequently associated with anovulation. Serum prolactin values showed no close correlation with the degree of menstrual abnormalities or galactorrhoea. Basal FSH and LH levels and the gonadotropin response to LH-RH were essentially normal in hyperprolactinaemia. Circulating E2 levels were largely subnormal suggesting an inhibitory effect of prolactin on ovarian E2 production. Prolactin levels over 100 ng/ml are suggestive of pituitary adenoma.
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PMID:Hyperprolactinaemia and female infertility. 644 Jan 15

59 patients affected by amenorrhea or anovulation, 37 of whom also with galactorrhea, and with hyperprolactinemia of unknown origin (idiopathic hyperprolactinemia, 24 patients) or due to a pituitary microadenoma (tumoral hyperprolactinemia, 35 patients) were treated with metergoline (4-12 mg/day) or with bromocriptine (2.5 to 10 mg/day) for 90 days. The effectiveness of the two treatments was assessed on clinical grounds and by evaluating at monthly intervals serum progesterone levels, during the presumed luteal phase, and serum prolactin levels. The success rate with the two drugs was superimposable in terms of disappearance of galactorrhea and return of menses, normalization of prolactin levels and induction of ovulation. Also the number of pregnancies obtained (7 with metergoline, 9 with bromocriptine) was similar. With both drugs, the majority of patients responded to the treatment within the first month.
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PMID:Metergoline and bromocriptine in the management of tumoral and idiopathic hyperprolactinemia. 661 28

Serum prolactin (PRL) was estimated for up to 2 months after discontinuation of therapy with either bromocriptine (n = 33; 15 with idiopathic disease, 12 with pituitary microadenoma, and six with macroadenoma) or metergoline (n = 23; 11 with idiopathic disease, and 12 with microadenoma) that had been administered for 8-30 months. Only five patients treated with bromocriptine and two treated with metergoline had PRL levels that remained normal or below 50% of pretreatment values. Among the patients followed-up for up to 12 months, four showed a fall in PRL at 3-4 months, but this was followed by a rise in one patient. Five patients showing persistently lower or normal PRL after drug withdrawal were retested with thyrotrophin-releasing hormone; the two responsive women also had a normal response before treatment. Of 10 patients followed for 9 months, three had persistently normal PRL levels. Amenorrhoea and anovulation recurred, with some delay, in all the patients showing PRL rebound except one. Medical treatment of hyperprolactinaemia only rarely results in permanent benefit.
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PMID:Serum prolactin and ovarian function after discontinuation of drug treatment for hyperprolactinaemia: a study with bromocriptine and metergoline. 670 49

Depressive illness has been associated with reversible abnormalities in the pituitary response of growth hormone, prolactin, and ACTH-cortisol. We saw similar neuroendocrine abnormalities in a patient with pseudocyesis. Normalization of the hormonal responses occurred with resolution of the pseudocyesis. Ovarian responsiveness to HCG suggests pseudocyesis to be of central hypothalamic-pituitary origin similar to polycystic ovarian disease, with neuroendocrine data consistent with reversible depression. In patients with affective illness, ovulatory disturbances may be the presenting symptom. Thorough psychosocial evaluation may be an important tool in the diagnosis of and therapy for anovulation.
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PMID:Neuroendocrine indices of depression in pseudocyesis. A case report. 670 24

This study was designed to characterize pituitary function in premenopausal women during hypothyroid and euthyroid periods. Six subjects with basal thyroid-stimulating hormone (TSH) levels above 10 microU/ml were studied. Estradiol (E2), prolactin (PRL), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) levels were measured by radioimmunoassay at 30, 15, and 0 minutes before infusion. Pituitary function was evaluated by rapid infusion of 10 micrograms of luteinizing hormone-releasing hormone (LHRH) every 2 hours for a total of 6 hours. Samples were then obtained for FSH and LH every 30 minutes for the duration of the 6-hour study. A significant elevation in basal gonadotropins was observed during the hypothyroid period regardless of basal E2 levels in all 6 subjects (P < .01). Basal PRL levels were not significahtly different during the 2 periods (P > .05). In all 6 patients pituitary sensitivity and reserve correlated significantly with basal E2 levels (P < .05), but were not altered by the hypothyroid condition. It is concluded that pituitary responsiveness to LHRH is not altered in hypothyroid women, but that chronic elevation of basal gonadotropins may in part explain the anovulation that so often accompanies this disorder.
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PMID:Pituitary response to LHRH in hypothyroid women. 677 59

This paper presents a review of the literature concerning the interaction between prolactin and gonadotropin release. Although the role of dopamine in the control of gonadotropin secretion is very important, other agents are involved in prolactin secretion, such as serotonin, opiate receptor agonists, and estrogens. Around the time of ovulation there is a surge of luteinizing hormone (LH) and changes in serum levels of prolactin, possibly due to an increase in estrogen secretion during the preovulatory period. The increase in prolactin level is probably not directly involved in normal secretion of LH and follicle stimulating hormone (FSH) at ovulation. A rise in prolactin may simply reflect a decrease in hypothalmic secretion of dopamine. High levels of prolactin during lactation inhibit gonadotropin secretion and result in amenorrhea. Lactational amenorrhea may be dependent on the suckling stimulus experienced at breast feeding, or on hyperprolactinemia. It seems that elevated prolactin levels are sufficient to cause anovulation by inhibiting LH and FSH secretion. The author conducted tests on hyperprolactinemic male adult rats and concluded that high prolactin levels may sensitize the hypothalamus to the negative feedback effects of gonadal steroids. Further studies are needed to clarify all phenomena related to prolactin secretion and its effects on alterations of LH and FSH secretion.
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PMID:Prolactin and the control of gonadotrophin secretion in the female. 677 67

Bromocriptine is known to be effective in the treatment of women with hyperprolactinemic anovulation or amenorrhea-galactorrhea. A new schedule of combined treatment with bromocriptine and clomiphene citrate was applied to 23 patients with normoprolactinemic amenorrhea who failed to respond to clomiphene alone. Ovulation was restored through treatment in 14 of these patients (60.9%) and pregnancy resulted in 3 women. Also, treatment resulted in immediate suppression of serum prolactin levels and a gradual increase in serum luteinizing hormone levels and estradiol levels followed by a luteinizing hormone surge. The present results indicate that bromocriptine/clomiphene citrate therapy is effective in the treatment of amenorrheic patients with normoprolactinemia who do not respond to clomiphene alone, and suggest that bromocriptine restores the responsiveness of the hypothalamic-pituitary-ovarian system to clomiphene.
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PMID:Induction of ovulation in patients with normoprolactinemic amenorrhea by combined therapy with bromocriptine and clomiphene. 678 35


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