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Query: UMLS:C0021359 (infertility)
 26,075 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aim of this work was to study the endocrine changes that occur during the reinstatement of the ovulatory cycles after lactational infertility in the rat. Hormonal patterns and specific binding of [125I]FSH to ovaries of lactating rats that kept their pups (LRP) or were separated from their pups on day 13 postpartum (LRX) were studied on days 13-16 postpartum. In LRP rats gonadotropin levels remained low and unvarying throughout the experiment; PRL levels were high in the morning, low at 1300 h, and then surged in the afternoon. Estradiol levels were very low in LRP rats in serum as well as in ovarian homogenates, and progesterone levels decreased gradually from days 13 to 16. No changes in either receptor number or dissociation constants (Kd) were observed in [125I]FSH binding to ovaries of LRP rats. In LRX rats, LH peaked on the afternoon of day 15 (P less than 0.05). FSH decreased from morning levels on day 13 to morning levels on day 15, and then peaked at 1600 h on day 15 (p less than 0.05). PRL decreased rapidly (day 13 1600 h levels significantly lower than day 13 1100 h levels), then remained low and peaked on the afternoon of day 15 (P less than 0.05). IN LRX rats progesterone levels decreased more markedly than in LRP rats and then surged in the afternoon of day 15. Serum estradiol levels rose significantly in the morning of day 15, while ovarian homogenate estradiol titers had already risen on the morning of day 14. Significant increases in number of [125I]FSH-binding sites and Kd values were observed in LRX rats on day 15 postpartum. These results clearly show that litter removal at midlactation (day 13) induces the reinstatement of hormonal cyclicity, and this is accompanied by changes in ovarian FSH receptors.
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PMID:Ovarian follicle-stimulating hormone binding changes associated with the reinstatement of ovulatory cycles after lactation interruption in the rat. 210 5

1. Prolactin is a 21,500 Dalton single-chain polypeptide hormone but may occur in 50 kDa and 150 kDa molecular variants. 2. These large PRL variants may be secreted predominantly; this condition is termed "macroprolactinemia". It is characterized by high immunological and normal biological serum levels of prolactin, and lack of clinical symptoms of hyperprolactinemia. 3. The information on PRL is encoded on chromosome 6. Transcription can be enhanced and suppressed by a variety of hormonal factors. 4. PRL is secreted in a pulsatile fashion; it displays a circadian rhythm (with a maximum during sleep) and is stimulated by some amino acids. PRL also responds to mechanical stimulation of the breast. 5. PRL rises during pregnancy, and maintainance of hyperprolactinemia (and, thereby, physiological infertility) is dependent on the frequency and duration of breast feedings. 6. Hypothalamic regulation of prolactin mainly involves tonic inhibition via portal dopamine. The physiological importance of various stimulating factors present in the hypothalamus is still incompletely understood. In particular, there is still no place for TRH in PRL physiology. 7. PRL is released in response to stress; this response may be mediated by opioids. The low-estrogen, low-gonadotropin amenorrhea of endurance-training women is not mediated by prolactin, however. 8. Estrogens stimulate PRL gene transcription via at least two independent mechanisms. There are many clinical examples of this estrogen effect on prolactin serum levels, and also on the growth of prolactinomas. 9. Mild hyperprolactinemia remains an enigma which cannot satisfactorily be resolved by biochemical or radiological testing. The border between "normal" and "elevated" prolactin is ill-defined. The possibility of macroprolactinemia complicates this matter even further. 10. The number of drugs which suppress prolactin by acting on pituitary D2 receptors, and which are useful in the treatment of hyperprolactinemia, continues to increase. In the field of ergot alkaloids, parenteral application appears to be a logical solution to the problem of the high first-pass effect; in addition, this form of treatment is frequently better tolerated than the oral route. 11. Prolactinoma development is presently being studied employing molecular biological techniques; the question of whether tumorigenesis can be attributed to specific defects of gene regulation remains to be answered.
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PMID:Control of prolactin secretion. 212 9

For sensitive assessment of thyroid function a TRH stimulation test using 200 micrograms TRH i.v. was routinely performed in 304 women admitted for evaluation and treatment of infertility. In 37 cases (12.2%) the reaction of TSH 30 min after injection of TRH i.v. was enhanced (by definition of a peak TSH level greater than 25 mIU/l), according to mild or subclinical hypothyroidism. Approximately 14 (14/37 = 37.8%) of these patients were found to have slightly elevated serum PRL values (mean PRL greater than 15 ng/ml). Cycle analysis by means of basal body temperature and evaluation of progesterone and oestradiol values, supplied evidence of luteal phase deficiency in 8 and anovulation in 3 cases. Another group of 11 patients with hypothyroidism involved oligo-/amenorrhoea, hirsutism and hyperandrogenaemia. After treatment with 50-150 micrograms l-thyroxine daily for at least 4 to 6 weeks, elevated PRL values significantly decreased (mean level less than 15 ng/ml, p less than 0.01) in 9 out of 12 patients and testosterone levels slightly decreased in 5 out of 8 patients. An improvement of the cyclical ovarian function could be observed by the significant increase of the average progesterone concentration in the luteal phase. During therapy with l-thyroxine, 4 pregnancies occurred. From these results we conclude, that mild hypothyroidism may cause ovarian insufficiency. Assessment of thyroid function should be mandatory in infertile patients with elevated prolactin levels or chronic anovulation.
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PMID:[Preclinical hypothyroidism and disorders of ovarian function]. 251 Oct 57

21-Hydroxylase-deficient late-onset adrenal hyperplasia (LOAH) appears to affect 1-6% of hyperandrogenic women. Screening and diagnostic criteria for LOAH have not been well established, as these patients are clinically indistinguishable from other hyperandrogenic women. The following prospective study was undertaken to 1) determine the predictive value of screening hyperandrogenic women for LOAH with a morning follicular phase basal 17-hydroxyprogesterone (17-HP) level and 2) compare the various in vivo estimates of 21-hydroxylase activity after adrenal stimulation for the diagnosis of LOAH. Twenty-one euandrogenic control women (physically normal, without hirsutism, with regular menses, and a negative family history) were studied. The clinical population consisted of 164 consecutive unselected patients seen at the Division of Reproductive Endocrinology and Infertility of Johns Hopkins University School of Medicine between 1983 and 1987 demonstrating hirsutism and/or hyperandrogenic oligomenorrhea. Controls and patients underwent acute adrenal stimulation with 1 mg ACTH-(1-24), administered in the morning to fasting patients in the follicular phase of their menstrual cycle. Blood was sampled before and 30 min after ACTH-(1-24) administration. Steroid RIA determinations were performed for 17-HP, progesterone, testosterone, dehydroepiandrosterone sulfate, androstenedione, FSH, LH, and PRL. Three estimates of 21-hydroxylase activity were studied: the 17-HP level 30 min post-ACTH (17-HP30), the change in 17-HP (delta 17-HP0-30) and the summed rate of change in 17-HP and progesterone ([delta 17-HP0-30) + delta P0-30]/30 min). The upper 95th percentiles for these estimates of 21-hydroxylase activity in control women were 9.6 nmol/L (316 ng/dL), 8.8 nmol/L (292 ng/dL), and 0.39 nmol/L.min (13 ng/dL.min), respectively. Thirteen of 164 (7.9%) hyperandrogenic women had at least 1 abnormal 21-hydroxylase measurement. Four of these women (2.4%) had 17-HP measurements 3- to 20-fold above the upper normal 95th percentile (17-HP30 greater than 36.3 nmol/L or 1200 ng/dL) and were considered as suffering from LOAH. In our population the 3 measures of 21-hydroxylase studied clearly differentiated the LOAH women from all others, although a single 17-HP level 30 min post-ACTH was the simplest and most cost effective. Nine other hyperandrogenic women (5.5%) had at least 1 abnormal 21-hydroxylase measurement less than 3-fold the upper normal 95th percentile value and were designated as having mild 21-hydroxylase deficiency.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:21-Hydroxylase deficiency in female hyperandrogenism: screening and diagnosis. 254 27

The authors evaluated the therapy by means of clomiphene++ and hCG in a group of 34 menstruating women aged 18-41 who suffered from ovarian infertility and hyperprolactinaemia not exceeding 100 ng/ml. Previous treatment of the women by means of bromoergocryptine decreasing the prolactin concentration did not provoked ovulation. It was found that moderate hyperprolactinaemia still blocked ovulation in one third of the women undergoing therapy. In a group of patients with a concentration of PRL from 50 to 100 ng/ml of blood serum there was a lower percentage of ovulation (62% v 67%) and subsequent pregnancies (23% v 33%). The authors did not find hypofunction of corpus luteum in women who reacted to the therapy. The average progesterone concentration amounted to 11.2 +/- 2.6 ng/ml of blood serum. The hormone concentration was significantly lower in a group of women with prolactinaemia exceeding 50 ng/ml (10.4 +/- 2.5 ng/ml vs 12.6 +/- 3.1 t = 1.86, p less than 0.1). The course of subsequent pregnancies in all cases, also in the group of women with prolactinaemia exceeding 50 ng/ml, was favourable.
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PMID:[Evaluation of the treatment of ovarian infertility in women with moderate hyperprolactinemia]. 268 Jul 89

The authors have studied, in 120 women with sterility, the incidence of endometriosis in the laparoscopic diagnostics, the development of pathology after the treatment by Danazol alone (600 mg/daily/6 months) or preoperative Danazol and subsequent conservative surgery, the sera RIA levels of FSH, LH, PRL, 17 beta-oestradiol and progesterone during therapy, the pelvic findings in the laparoscopic second look and the pregnancy rates after the treatment. On the findings of the obtained results, which agree with the most recent studies, the authors point out the significance of laparoscopy in the diagnosis and staging of endometriosis; the correlation between staging and different therapies; the peculiarity of the laparoscopic second look in monitoring endometriosis evolution after therapy and at last the deep correlations, not yet well explained, among the mild endometriosis and alterations as the luteal phase defect and the anovulatory both in the acute fitness of the pathology and after treatment by Danazol alone or preoperative Danazol with subsequent conservative surgery as shown by persistence of sterility or of infertility, although without other well-known reasons which could explain the subsequent pregnancy failures.
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PMID:Laparoscopic findings and hormonal patterns in the treatment of endometriosis by danazol. 295 84

In a longitudinal study one healthy man aged 26 yrs underwent semen collections and blood samplings at monthly interval from January to December 1985. The ejaculated samples were analyzed for sperm density, motility, relative proportion of early (ab) and late (cd) spermatids, concentrations of Fructose, L-Carnitine and Transferrin. In a transverse study, 248 serially independent samplings were performed of normal men, 28.9 +/- 7.5 yrs old, consulting for infertility from January 1981 to December 1983. The Cosinor method was employed for searching on circannual rhythms of the studied parameters. The longitudinal study did not detect circannual rhythms of the considered seminal parameters nor of the studied hormones. However, peaks, significantly above the mean values throughout the year (p less than 0.005), were observed of Cortisol, PRL, FSH, LH, Testosterone, Fructose and L-Carnitine levels. Young spermatids and sperm motility showed significant (p less than 0.001) acrophases between June and July; an acrophase was also evident for late spermatids but shifted by six months, between December and January. Mesors and amplitudes were respectively: 28 +/- 1.5 and 9.6 +/- 4.3 (mean +/- SE) for motility; 33.4 +/- 1.6 and 9.9 +/- 5 for early spermatids; 46.6 +/- 1.9 and 13 +/- 6.2 for late spermatids.
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PMID:Circannual rhythms in reproductive functions of human males, correlations among hormones and hormone-dependent parameters. 311 44

We report two cases of the XX-male syndrome, and review the literature. The first case was a 31-year-old married man, a welder, complaining of infertility. His height was 158 cm, weight 82 kg and distance of extended hand 155 cm. The external genitalia showed a normal male type, but bilateral small testes and gynecomastia were noticed. The second case was a 32-year-old married man, a shopkeeper, complaining of infertility. His height was 165 cm, weight 60 kg and distance of extended hand 167 cm. No gynecomastia was noted. The external genitalia showed a normal male type, but bilateral small testes were noticed. In each case, azoospermia was identified in semen analysis. Urethrography revealed the prostatic utricle in the second case. The testicular biopsy specimens revealed hyalinization of seminiferous tubules and proliferation of Leydig cells. X chromatin was positive in buccal smears, and Y chromatin negative in cultured lymphocytes. Chromosomal analysis showed 46, XX karyotype in the first case and 46, XXp+ in the second case. H-Y antigen was positive in each case. Basal serum levels of LH and FSH were moderately elevated and the serum testosterone level was low. Serum levels of PRL, TSH, estradiol, GH, T3 and T4 were normal. An impaired response by testicular Leydig cells to hCG was observed. The LH and FSH responses to LH-RH were almost normal. Clomiphene citrate administration resulted in a decrease in the serum testosterone and gonadotropins levels. These results indicate hypergonadotropic hypogonadism secondary to testicular failure in both XX-males. Twenty-six cases of the XX-male syndrome have been cited in the Japanese literature. The clinical features and etiology of this syndrome are discussed.
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PMID:[Male infertility with chromosomal abnormalities. II. XX-male syndrome]. 359 82

To determine the acute and chronic effects of suckling on maternal PRL secretion in monkeys, five mother-infant pairs were studied longitudinally on days 40, 80, 120, and 10 after weaning (day 160). Mothers were chronically cannulated and, during blood collections, wore protective nylon vests with mobile tethers. Studies were undertaken during the day and night with the mother and infant undisturbed, during the daytime, before and after the removal of the infant, and during the day and night before and after the reunion of mother and infant. Maternal PRL levels were significantly (P less than 0.05) higher at night than during the day in undisturbed mother-infant pairs. This nocturnal elevation was probably induced by a more intensive interaction of the mother and infant at night than during the day. Basal PRL concentrations in samples collected during these undisturbed settings significantly (P less than 0.05) declined as the postpartum interval continued. The removal of the infant did not perturb maternal PRL patterns. Typically, after reunion of mother and infant, maternal PRL levels were increased significantly (P less than 0.05), reaching maximal levels approximately 2 h after reunion. If PRL secretion, induced by the suckling stimulus, is instrumental in sustaining puerperal infertility, then the increased secretion of PRL that occurs at night during the protracted interval of intense mother-infant interaction may be of particular significance in inhibition of the hypothalamic-pituitary-ovarian axis.
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PMID:Lactational amenorrhea in monkeys: effects of suckling on prolactin secretion. 384 78

A specific PRL unresponsiveness to TSH-releasing factor was uncovered during the workup of an obese man with infertility due to oligozoospermia. Normal PRL responses were demonstrated in response to insulin-induced hypoglycemia, MTC, and sleep. Borderline-low circulating T without elevated baseline LH levels which rose in response to clomiphene citrate and normal LH and FSH responses were noted after LH-RH administration, indicating normal pituitary responsiveness, even though occurring in the presence of hypothalamic dysfunction, affecting pituitary gonadal relations, appears located in the pituitary and limited to a single stimulus: TSH-releasing factor.
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PMID:Specific prolactin release refractoriness to thyroid-stimulating hormone-releasing factor in an obese infertile man. 391 6


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