Pulsatile secretion of prolactin and luteinizing hormone and their synchronous relationship during the human menstrual cycle

Recent investigations have demonstrated the pulsatile nature of prolactin (PRL) secretion and the synchronous relationship between PRL and LH pulses in normal and hypogonadal women. The present study was designed to confirm this synchrony and to investigate the characteristics of PRL pulses at different stages of the menstrual cycle. Blood samples were obtained at 10-minute intervals, beginning at 10.00 hours, for a duration of 4-7 hours, from women during the follicular (n = 11), preovulatory (n = 2) and luteal (n = 10) phases. Detectable pulses in plasma PRL concentrations were present in almost all subjects during each phase of the cycle. During the total 121-hour blood sampling throughout the 3 phases, 62 PRL pulses and 74 LH pulses were detected and about 80% of the PRL pulses were observed to coincide with LH pulses. The mean (+/- SD) pulse frequency of PRL was significantly lower during the luteal phase (0.28 +/- 0.17 pulses/hour) than during the follicular (0.64 +/- 0.25 pulses/hour) and preovulatory (0.72 +/- 0.16 pulses/hour) phases, while the mean pulse amplitude of PRL was significantly greater during the luteal phase (6.8 +/- 2.3 ng/ml) than during the follicular (3.6 +/- 1.2 ng/ml) and preovulatory (4.1 +/- 1.0 ng/ml) phases. These changes in pulse frequency and amplitude were also observed in LH pulses between the follicular and luteal phases, except at the LH surge, when LH pulse amplitude increased markedly, but that of PRL did not alter. Furthermore, a positive linear correlation between the pulse frequency of PRL and LH (r = 0.74, p less than 0.001) was found throughout the 3 phases of the cycle. These results demonstrate that a marked degree of synchrony between PRL and LH pulses is observed during the menstrual cycle and suggest that the frequency and amplitude of PRL pulses vary from the follicular to luteal phases, except at the LH surge, almost in parallel with those of LH pulses.     

The effect of thyrotropin-releasing hormone stimulation on serum levels of gonadotropins in women during the follicular and luteal phases of the menstrual cycle

Thyrotropin-releasing hormone (TRH) can stimulate the secretion of adenohypophyseal thyroid-stimulating hormone and prolactin (PRL). The effect of TRH on gonadotropin secretion has not been well defined. This study investigated the effect of TRH administration on the peripheral levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) during the early follicular and midluteal phases of the menstrual cycle in five ovulatory, euthyroid, and normoprolactinemic women. Two hundred micrograms of TRH were administered intravenously on days 3 to 5 and on days 21 to 23 of the same cycle. LH and FSH were measured prior to and every 30 minutes for 2 hours following TRH injection. Ovulation was confirmed in all cycles by midluteal progesterone. All women had normal thyroid-stimulating hormone (TSH) and PRL responses to TRH stimulation in both cycle phases. Baseline and stimulated gonadotropin levels were analyzed by analysis of variance. Thirty minutes following TRH infusion, follicular and luteal levels of LH (mIU/ml, mean +/- standard error of the mean) significantly increased from 6.0 +/- 0.8 to 8.0 +/- 1.1 (P less than 0.005), and from 4.8 +/- 0.6 to 7.6 +/- 0.7 (P less than 0.005), respectively. Levels of FSH increased during both phases of the cycle, but the elevation was not statistically significant. These results suggest that TRH can stimulate gonadotrope secretion of LH, but not of FSH, in both the follicular and luteal phases of the cycle.     

Pulsatile secretion of prolactin during the human menstrual cycle

Recent investigations have demonstrated the pulsatile nature of prolactin (PRL) secretion and the synchronous relationship between PRL and LH pulses in normal and hypogonadal women. The present study was designed to confirm this synchrony and to investigate the characteristics of PRL pulses at different stages of the menstrual cycle. Blood samples were obtained at 10-min intervals beginning at 1000 h for a duration of 4-7 h in women during the follicular (n = 11), preovulatory LH surge (n = 2) and luteal phases (n = 10). Detectable pulses in plasma PRL concentrations were present in almost all subjects during the each phase of the cycle. During the total 121 h-blood sampling throughout the three phases, 62 PRL pulses and 74 LH pulses were detected and about 80% of these PRL pulses were observed to coincide with LH pulses. The mean (+/- SD) pulse frequency of PRL was significantly lower during the luteal phase (0.28 +/- 0.17 pulses/h) than during the follicular (0.64 +/- 0.25 pulses/h) and preovulatory phases (0.72 +/- 0.16 pulses/h). The mean pulse amplitude of PRL was significantly greater during the luteal phase (6.8 +/- 2.3 ng/ml) than during the follicular (3.6 +/- 1.2 ng/ml) and preovulatory phases (4.8 +/- 1.4 ng/ml). These changes in pulse frequency and amplitude were also observed in LH pulses between the follicular and luteal phases, except during the LH surge when LH pulse amplitude increased markedly, whereas that of PRL did not alter. Further, a positive linear correlation between the pulse frequency of PRL and LH (r = 0.74; p less than 0.001) was found throughout the three phases of the cycle.(ABSTRACT TRUNCATED AT 250 WORDS)     

Elevated early follicular gonadotropin levels in women with unexplained infertility do not provide evidence for disordered gonadotropin-releasing hormone secretion as assessed by luteinizing hormone pulse characteristics

OBJECTIVE: To determine whether women with rigorously defined unexplained infertility demonstrated altered GnRH secretion, as reflected by serum LH secretion patterns. DESIGN: Prospective observational study. SETTING: National Center for Infertility Research at Michigan. PATIENT(S): Nine women with rigorously defined unexplained infertility and 11 healthy, parous age-matched control women.Gonadotropin-releasing hormone (25 ng/kg) as a bolus injection. MAIN OUTCOME MEASURE(S): Daytime pulse patterns of LH secretion measured every 10 minutes; mean serum concentrations of LH, FSH, E(2), P, PRL, and cortisol; and response to a physiologic dose of GnRH in the early follicular, late follicular, mid-luteal, and late luteal phases of the same menstrual cycle. RESULT(S): Serum LH pulse frequency and pulse amplitude and LH secretion in response to a physiologic bolus of GnRH were not significantly different in unexplained infertility patients at any phase of the cycle. Luteinizing hormone pulse frequency and amplitude, as well as response to GnRH, varied significantly across the cycle. Mean early follicular serum LH and FSH concentrations were significantly higher in unexplained infertility patients than in fertile control subjects (LH: 5.31 +/-.51 vs. 4.03 +/-.33 [mIU/mL +/- SEM]; FSH: 5.81 +/-.63 vs. 3.80 +/-.45) but were not different at any other phase of the cycle. CONCLUSION(S): These data do not support the hypothesis that unexplained infertility is caused by an abnormality in pulsatile GnRH secretion or abnormal pituitary sensitivity to GnRH. However, the results are consistent with a difference in negative feedback from the ovary to the pituitary in unexplained infertility patients that is suggestive of diminished ovarian reserve.     

Transient hyperprolactinemia in infertile women with luteal phase deficiency

This study was conducted to evaluate the prevalence of transient hyperprolactinemia in infertile women with luteal phase deficiency. One hundred fifty-one luteal phase deficiency patients and 11 controls had serum prolactin (PRL) measured daily for 3-4 days near ovulation. Thirty-three subjects (21.9%) had transient hyperprolactinemia, with PRL above 20 ng/mL for 1 or 2 days, and were studied further. The blood samples of these 33 subjects and of the controls were also analyzed for LH and FSH. Plasma progesterone was measured on the fourth, seventh, and tenth days after ovulation in both groups. The mean (+/- SD) of the mid-cycle integrated LH surge (125.0 +/- 23.0 mIU/mL; N = 26) and the sum of three plasma progesterone levels (23.8 +/- 4.5 ng/mL; N = 21) in the luteal phase deficiency women were significantly (P less than .001) lower than those of the controls (LH 158.7 +/- 13.8 mIU/mL; progesterone 33.8 +/- 6.5 ng/mL). All 33 luteal phase deficiency subjects with transient hyperprolactinemia were treated with bromocriptine at a dose ranging from 1.25-5 mg/day to maintain mid-cycle PRL levels between 5-15 ng/mL. Both the integrated LH surge and the sum of three progesterone levels increased significantly (P less than .05) during bromocriptine treatment, to 142.6 +/- 22.4 mIU/mL (N = 20) and 28.2 +/- 6.2 ng/mL (N = 18), respectively. Fourteen of the 33 patients conceived. The cumulative probability of conception was 31% for six cycles and 45% for 12 cycles of treatment.(ABSTRACT TRUNCATED AT 250 WORDS)     

Episodic luteinizing hormone release in hyperprolactinemic women

Episodic luteinizing hormone (LH) secretion was studied in 16 hyperprolactinemic women (microprolactinoma, 12; idiopathic, 4) with amenorrhea of 1.4 to 7 years' duration. Blood samples obtained through an indwelling venous catheter at 20-minute intervals over 5 hours were assayed for LH, follicle-stimulating hormone (FSH), prolactin (PRL), and estrogen (E) (selected samples). LH pulse patterns were divided arbitrarily into high-amplitude release (LH pulse greater than 10 mIU/ml) (n = 7), low-amplitude release (LH pulse less than 10 mIU/ml (n = 6), and no release (n = 3). Mean pulse frequencies in women with high-amplitude and low-amplitude release were 2.4 +/- 0.3 (mean +/- standard error) and 1.3 +/- 0.2 pulses/5 hours and differed significantly (P greater than 0.02), whereas mean percentages of secretory increment were 155% and 62%, respectively. Mean LH concentrations in the high-amplitude (18.0 +/- 0.8 mIU/ml), low-amplitude (13.2 +/- 0.6 mIU/ml), and no-pulse groups (7.5 +/- 0.2 mIU/ml) differed significantly (P greater than 0.02). Despite the different pulse patterns, mean serum FSH, PRL, and total E concentrations were similar. The lack of episodic LH release and/or low infrequent LH release could account for the absence of cyclic hypothalamic pituitary ovarian function, although other mechanism(s) may be operative in women with augmented LH secretory pulses.     

Lipid and hormonal profile of Panamanian women during the menstrual cycle.

Forty-one women of reproductive age were included in the study, to establish the variation of serum lipids during the menstrual cycle and simultaneously, to determine the physiological fluctuation of FSH, LH, prolactin (PRL), progesterone (P4) and estradiol (E2) concentration in serum, during the menstrual cycle. A significant decrease of total serum cholesterol (165.29 +/- 3.6 mg/dl) and triglycerides (108.99 +/- 9.65) occurred during the luteal phase, as compared with the follicular phase (176.16 +/- 3.51, 108.99 +/- 9.65). Changes were not observed with HDL-cholesterol during the cycle. On the other hand, FSH showed an initial rise (mean 5 IU/l) followed by a surge (10 IU/l) and a progressive fall toward the midcycle. In contrast LH secretion showed a steady increase with a maximal concentration at surge (32.1 IU/l). PRL mean value was observed, with a discrete increase after day 13 of the menstrual cycle, that was more noticeable at the end of the cycle. Forty-eight hours after the FSH and LH midcycle surge, elevation of progesterone was observed, with maximal concentration occurring on day 24 (23 nmol/l) and later on progesterone levels fell rapidly. Thirty-six to 24 h before the surge of LH and FSH at midcycle was observed the peak serum concentration of estradiol (1300 pmol/l) followed by a progressive fall. Changes in the concentration of serum lipids during the menstrual cycle are presumably due to a direct or indirect effect of physiological fluctuation of sex hormones.     

Subnormal 24-hour mean plasma LH concentration and elevated plasma FSH/LH ratio in obese premenopausal women. A possible human counterpart of the slow-GnRH-pulsing model in primates

The 24-hour mean plasma concentrations of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were measured during the follicular phase of the menstrual cycle in 15 healthy, regularly cycling obese women (59-218% above desirable weight) and 9 healthy, regularly cycling nonobese women (14% below to 14% above desirable weight). The obese women showed slightly but not significantly higher FSH values (12.5 vs. 9.6 mIU/ml), definitely and significantly lower LH values (11 vs. 17 mIU/ml; p less than 0.005) and markedly and very significantly higher FSH/LH ratios (1.2 vs. 0.62; p less than 0.0005). These abnormalities may represent a human counterpart of the slow-GnRH-pulsing model of primates: monkeys in which the GnRH secretory centers have been ablated and that receive GnRH infusions at subnormal pulsing rates show slightly elevated FSH levels, markedly decreased LH levels, greatly elevated FSH/LH ratios and anovulation.     

Estradiol, FSH and LH profiles in nine ethnic groups of postmenopausal Asian women: the Pan-Asia Menopause (PAM) study.

OBJECTIVES: Significant differences in the prevalence of menopausal symptoms and in lipid profiles have previously been reported for nine ethnic groups of postmenopausal Asian women participating in the Pan-Asia Menopause (PAM) study. Based on these findings, we tested the hypothesis that reproductive hormone profiles differ among the nine ethnic groups under investigation in the PAM study. METHODS: Baseline serum samples from postmenopausal women (n=1020) representing nine ethnic groups were analyzed at a central laboratory by electro-chemiluminescence immunoassay methods. Hormone concentrations were measured for estradiol (E2), follicle stimulating hormone (FSH) and luteinizing hormone (LH). RESULTS: The hormone levels for the overall study population (mean+/-SD) were: E2=74.1+/-125.1 pmol/l (n=1015); FSH=81.2+/-31.4 IU/l (n=1013); LH=36.8+/-15.6 IU/l (n=1015). Estradiol levels ranged from 50.0 pmol/l in Chinese women to 106.8 pmol/l in Vietnamese women; FSH ranged from 68.2 IU/l in Korean women to 90.8 IU/l in Malay women; and LH ranged from 30.7 IU/l in Korean women to 44.1 IU/l in Malay women. There was an inverse correlation between log E2 and FSH levels and a positive correlation between FSH and LH levels. The concentrations of E2, FSH and LH were significantly associated with ethnicity after adjustment for age and body mass index. Additionally, the concentrations of all three hormones were significantly associated with body mass index, whereas E2 and LH levels were associated with age, but FSH levels were not. CONCLUSION: The levels of FSH, LH and particularly of E2 differ substantially among ethnic groups of postmenopausal Asian women. The clinical significance, if any, of these differences remains to be investigated. The inverse correlation of E2 and FSH levels suggests that E2 at the postmenopausal state still affects pituitary FSH output.     

Pituitary responses in LH secretion to LHRH during pregnancy.

Thirty-six pregnant women and 15 normally menstruating women were each given 100 microng of synthetic luteinizing hormone releasing hormone (LHRH) by a single intravenous injection. Human chorionic gonadotropin (hCG), luteinizing hormone (LH), and follicle stimulating hormone (FSH) levels were determined by specific radioimmunoassay (RIA) technics. For the determination of the serum LH levels, the LHbeta-RIA method, which is unaffected by hCG at sample levels as high as 500 IU/ml, was used. Serum concentrations of LH and FSH were lower in pregnant women than in the normal women in the follicular and luteal phases. While the release of LH was observed in pregnant women following the administration of LHRH, the average net increase was less than that seen in both the follicular and luteal phases. During pregnancy, there was a progressive decrease in the LH response to LHRH, but no release of FSH.     

Are follicle stimulating hormone measurements predictive of ovarian response to hyperstimulation with human menopausal gonadotrophin?

Previous studies have suggested that elevated serum follicle stimulating hormone (FSH) concentrations are associated with a poor ovarian response to hyperstimulation with human menopausal gonadotrophin (HMG) in in vitro fertilisation (IVF) programmes. We have used the day 2 serum FSH concentration to determine the dose of HMG administered in women under 40 years. If the FSH concentration was below 9 IU/l, a constant dose of 150 IU HMG were administered; if above 9 IU/l a constant dose of 300 IU HMG was used. Women over the age of 40 years were given 300 IU HMG regardless of their serum FSH concentration. This retrospective study was undertaken to assess whether this approach was beneficial for the younger women and also whether the FSH concentration was predictive of outcome in older women. The study included all women < 40 years (n = 143) and > 40 years (n = 32) having their first IVF treatment cycle during 1994. In the younger women, there was no difference in the number of cancelled treatment cycles (9.7% vs. 7.5%); the number of follicles present (9.6 vs. 8.2); serum oestradiol concentration (6971 pmol/l vs. 6686 pmol/l); number of eggs collected (7.9 vs. 5.7); number of embryos created (3.7 vs. 3.6); and pregnancy rate (13.5% vs. 15%) between women with normal (n = 103) or elevated (n =40) FSH concentrations. By using the serum FSH concentration to select women in whom a poor response was expected, and administering a higher dose of HMG, a similar ovarian response was produced and the pregnancy rate was similar to those in women with normal FSH concentrations. Women over 40 years with elevated serum FSH concentrations (n = 17) had a significantly (P < 0.05) higher cancellation rate (17.6% vs. 0%) and fewer number of eggs collected (6.9 vs. 2.5) than the group with normal FSH concentrations (n = 15). One woman conceived in each group. These findings confirmed previous studies showing that the serum FSH is predictive of ovarian response. This study confirmed the value of measuring the day 2 serum FSH concentration as a predictor of response; and it provides a scientific approach to determine the dose of HMG administered for IVF stimulation. A satisfactory response to induction of ovulation will be achieved using 150 IU HMG in women with FSH < 9 IU/l but if the FSH is raised i.e. above 9 IU/l, 300 IU is required to achieve a similar response.     

Exogenous melatonin enhances the TRH-induced prolactin release in normally cycling women: a sex-specific effect.

The aim of the present study was to analyze the effects of exogenous melatonin (MT) upon pituitary and adrenal responsiveness to releasing hormones in different phases of the menstrual cycle. We evaluated the response of FSH and LH to 100 micrograms gonadotropin releasing hormone, of TSH and prolactin (PRL) to 200 micrograms thyrotropin releasing hormone (TRH), and of cortisol to 10 micrograms ACTH 1-17. We studied eight young women with normal ovulatory cycles in the early follicular (days 5-7) and luteal (days 22-24) phases. Stimulation tests were performed at 18.00 in baseline conditions as well as 1 h after oral intake of exogenous MT (2 mg as a gelatine capsule). We did not observe any significant change in FSH, LH, TSH and cortisol responses to their respective releasing hormones in either phase of the cycle. PRL response to TRH was higher after MT in the follicular phase, when evaluated in terms of net increment and integrated area of response (p less than 0.02 versus baseline conditions for both variables). In the luteal phase, we recorded larger interindividual variability and higher responses after MT were observed in five out of eight subjects. These results suggest that MT may play a facilitatory role in the TRH-induced PRL release in women of reproductive age.     

Urinary reproductive hormone level differences between African American and Caucasian women of reproductive age

OBJECTIVE: To compare urinary levels of reproductive hormones in African American and Caucasian women. DESIGN: Cross-sectional study. SETTING: Ten United States Air Force (USAF) bases. PATIENT(S): African American (n = 33) and Caucasian (n = 65) women of reproductive age from a larger study of USAF women (n = 170). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Urinary endocrine end points: follicular luteinizing hormone (LH), preovulatory LH, level of LH surge peak, early follicular follicle stimulating hormone (FSH), follicular LH:FSH ratio, midluteal FSH, FSH rise before menses, early follicular estrone 3-glucuronide (E(1)3G), midfollicular E(1)3G, periovulatory E(1)3G peak, midluteal E(1)3G, early follicular pregnanediol 3-glucuronide (Pd3G), follicular Pd3G, rate of periovulatory Pd3G increase, E(1)3G:Pd3G on the day of luteal transition, slope of E(1)3G:Pd3G, and midluteal Pd3G. RESULT(S): Relative to Caucasians, African American women had significantly lower follicular phase LH:FSH ratios (mean +/- SD: 0.7 +/- 0.4 vs. 1.0 +/- 0.6), lower follicular phase Pd3G levels (1.0 +/- 0.5 vs. 1.2 +/- 0.8 microg/mg creatinine), and lower rates of periovulatory Pd3G increase (0.5 +/- 0.7 vs. 1.0 +/- 1.2 microg/mg creatinine). CONCLUSION(S): Findings of this analysis should be considered preliminary evidence of racial differences in hormone levels. Future studies are needed to determine whether these differences have clinical significance.     

Pituitary LH response to LHRH during puerperium.

Forty puerperal women and 15 normally menstruating women used as controls were given 100 microgram of synthetic luteinizing hormone releasing hormone (LHRH) in a single intravenous injection. Serum concentrations of luteinizing hormone (LH), follicle-stimulating hormone (FSH) and human chorionic gonadotropin (hCG) were measured by a specific radioimmunoassay (RIA). The LH-beta RIA method, which is unaffected by hCG at sample levels as high as 500 IU/ml, was used to determine serum LH levels. Basal serum FSH and LH levels determined immediately after delivery were lower than those in the follicular and luteal phases during the normal menstrual cycle. These levels rose gradually after delivery, and finally returned to normal levels during the 16th to 25th days of the puerperal period. Small, but significant, LH response to LHRH was observed 6-10 days after delivery, and gradually returned to normal thereafter, though the response was poor during the first 35 days of the puerperal period when compared with that of the controls. On the other hand, no FSH response to LHRH was observed until 16-25 days after delivery, when the response was greater than that of the controls.     

The effects of inducing a follicular phase gonadotropin secretory pattern in normal women during the luteal phase

It has been hypothesized that the slowing of the luteinizing hormone (LH) pulse frequency in the luteal phase may be necessary for the demise of the corpus luteum, the intercycle rise in baseline follicle-stimulating hormone (FSH), or ovarian follicular development in the subsequent cycle. For assessment of the physiologic role of the luteal phase LH pulse pattern, this pattern was converted to a follicular pattern in six normal women who used exogenous gonadotropin-releasing hormone administered with a portable pump (dose 50 to 100 ng/kg subcutaneously every 90 minutes beginning in the early luteal [n = 3] and midluteal [n = 3] cycle phases). There was no significant difference between the treated and the subsequent cycle for luteal progesterone production [186.3 versus 159.0 (ng/ml) day], preovulatory follicular size (23.1 versus 22.5 mm), estradiol levels, luteal phase length (15.6 versus 14.3 days), and daily gonadotropin concentrations including the intercycle FSH rise (160.5 versus 139.1 ng/ml). A follicular phase gonadotropin pulse pattern (increased frequency, decreased amplitude) in the luteal phase had no discernible effects on the corpus luteum or on follicular development in the subsequent cycle.     

Predictive value of the FSH:LH ratio on follicular and luteal phase characteristics of the human menstrual cycle

A prospective study was designed to assess the predictive value of gonadotropin measurements obtained during the early follicular phase upon the hormonal characteristics of the subsequent cycle. The data obtained in 12 normal cycles were used to compute the mean and confidence interval (mean +/- 2 SEM) of the FSH:LH ratio, FSH and LH plasma levels. The limits of the confidence intervals for these different parameters were used to classify the patients. Data of 204 patients were analysed. Low FSH:LH ratios (less than 1.34) are associated with an increase in follicular phase length (+2.4 days), a lower ovulatory rate, but neither luteal phase length nor progesterone levels differ between these two groups. When patients are classified according to FSH levels, our results show that low FSH levels (less than 2.94 mIU/ml) are associated with longer follicular (+2.6 days) and shorter (-1.1 days) luteal phase lengths, but ovulatory rate and progesterone levels in the luteal phase of the ovulatory cycles are similar to those obtained in patients of the normal or high FSH group. High LH levels (greater than 3.15 mIU/ml) are associated with a decreased ovulation rate but follicular and luteal phase characteristics are similar to those obtained in patients in the normal or low LH group. In conclusion, low FSH: LH ratios and low FSH plasma levels measured in the early follicular phase of the cycle are associated with longer follicular phase lengths; but basal gonadotropin measurements have limited predictive value on luteal phase characteristics.     

血清抑制素含量在月经周期中的变化及其与卵泡刺激素的相关性

目的了解育龄妇女在月经周期中血清抑制素(INH)含量的变化规律及其与卵泡刺激素(FSH)、黄 体生成素(LH)、雌二醇(E2)及孕酮(P)的相关性。方法建立一种改良的INH放射免疫测定法(RIA),对育龄妇 女正常月经周期中及绝经后妇女血清INH含量的变化进行监测;同时测定血清FSH、LH、E     

Elevated day 3 FSH/LH ratio due to low LH concentrations predicts reduced ovarian response

Adequate ovarian response, essential for successful IVF, cannot be accurately predicted. This study retrospectively reviewed all patients undergoing IVF from 1998 to 2001. Inclusion criteria were age <41 years at treatment onset and a basal day 3 serum FSH concentration <12 IU/l. Women with FSH or=3 in group 1 and <3 in group 2 (controls). Age at treatment initiation, basal serum day 3 FSH and LH concentrations, peak serum oestradiol concentration, number of retrieved and fertilized oocytes and pregnancy rate were analysed. Groups 1 (n = 41, 111 IVF treatment cycles) and 2 (n = 596, 1,434 IVF treatment cycles) were similar in term of woman's mean age. Group 1 had significantly higher mean basal day 3 FSH concentration (P < 0.01) and significantly lower oestradiol concentrations at oocyte retrieval (P < 0.01), mean number of oocytes retrieved and fertilized (P < 0.01) and pregnancy rate (P = 0.016). The same trend persisted after excluding 98 patients with basal FSH concentrations >8 IU/l. In conclusion, elevated day 3 FSH/LH ratio is associated with an inferior outcome in IVF treatment cycles and may be used as an additional predictor for decreased ovarian response.     

Pulsatile release of gonadotropins in athletic women

In athletic women menstrual disorders such as luteal insufficiency, oligomenorrhea and amenorrhea are often seen. It has been suggested that such disorders may be related to hypothalamic-pituitary axis insufficiency caused by physical activity. To investigate the mechanism by which the disorder is promoted, episodic gonadotropin secretion was studied in 10 athletic women (normal ovulatory, 5; short luteal, 5) and 6 non-athletic controls. In the early follicular phase of the menstrual cycle, blood samples were obtained through an indwelling venous catheter at 15-minute intervals for 4 hours. The concentrations of luteinizing hormone (LH) and follicle-stimulating hormones (FSH) were measured by radioimmunoassay. The mean LH and FSH concentrations in the athletic groups were lower than those in the control group. LH pulse frequencies in the short luteal group were 2.8 +/- 0.2 times/four hours (mean +/- standard error) and decreased compared with that of the control group (3.7 +/- 0.2 times/four hours; p less than 0.001). The LH pulse amplitudes of all three groups were similar. Pulsatile FSH secretion was also observed in all the women. Dynamism of FSH was the same as that of LH except for low pulse amplitude in the athletic groups. These data suggest that hypothalamic-pituitary axis insufficiency, especially of hypothalamic origin may be caused by athletic activity.     

Ovulation triggering in clomiphene citrate-stimulated cycles: Human chorionic gonadotropin versus a gonadotropin releasing hormone agonist

Purpose To compare the use of human chorionic gonadotropin (hCG) to a gonadotropin releasing hormone (GnRH) agonist, nafarelin, in initiating ovulation and supporting the luteal phase after priming with clomiphene.Methods In 26 infertile women 50 mg clomiphene citrate produced a preovulatory-size follicle. Then, 11 women were randomized to receive two 400-g doses of nafarelin intranasally 16 h apart, and 15 women were injected intramuscularly with 5000 IU of hCG (luteal day 0 = LD0). Starting on LD6, 7 more 400-g doses of nafarelin were repeated on an every 16-h schedule or a single 2500 IU dose of hCG was given, respectively. Serum levels of follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E₂), progesterone (P), and hCG were measured. On LD13, endometrium was evaluated with ultrasonography and biopsy in 19 nonpregnant women.Results As judged by a threefold rise in serum LH, an LH surge was detected on LD1 in all 11 nafarelin patients, but in only 8 hCG patients (P = 0.01). LH and FSH levels were significantly higher on LD1, 7, and 8 and were significantly suppressed on LD13 in the nafarelin group. All patients had mid-luteal P levels greater than 10 ng/ml and luteal phases longer than 13 days. Significantly different luteal E₂ or P levels were noted only on LD13, with lower values in the nafarelin group. Pregnancies were achieved in 3 of 11 nafarelin cycles and 2 of 15 hCG cycles. Luteal phase defects were also similar: 4 of 8 nafarelin patients and 7 of 11 hCG patients.Conclusion Nafarelin or hCG in conjunction with clomiphene can result in viable pregnancies, but is associated with low pregnancy rates and a high incidence of luteal phase defects.