Mean Follicle-stimulating Hormone Concentrations Research Articles

Roles of Follicle-Stimulating Hormone on Bone Metabolism in Late Postmenopausal Women.

BackgroundThe effects of elevated follicle-stimulating hormone (FSH) levels on physiological changes in the bone remain unclear. This study aimed to clarify the association between FSH concentrations and bone mineral density (BMD) and bone turnover markers (BTM) in late postmenopausal women.MethodsA total of 169 Korean women were enrolled. The participants’ ages ranged from 60 to 84 years (mean age, 69.0±5.1) and reported a mean duration of 19.4±6.6 years since menopause (YSM). The participants showed an average body mass index (BMI) of 24.4±2.8 kg/m2. Age, YSM, estradiol, testosterone, and BMI were confounders in the Pearson’s partial correlation. A test for trends across the quartiles of FSH levels was performed for each variable.ResultsThe mean FSH and estradiol concentrations were 61.5 IU/L and 2.9 pg/mL, respectively. Serum FSH concentration was not significantly associated with BMD (lumbar, r=0.09, P=0.30; total hip, r=0.00, P=0.96; and femoral neck, r=0.05, P=0.62). BTM across the FSH quartiles did not show any trend association (bone-specific alkaline phosphate, P=0.31; cross-linked C-terminal telopeptide of type I collagen, P=0.90). Instead, FSH levels were negatively correlated with BMI (r=−0.34, P=0.00). In the multivariate regression model adjusted for age, testosterone, and estradiol, only BMI showed a negative value across the FSH quartiles (β coefficient −0.11, P=0.00).ConclusionsThis study identified that high FSH concentrations were not associated with bone loss or high bone turnover in women in the late postmenopausal period.

Elevated serum malondialdehyde (MDA), insulin, follicle-stimulating hormone (FSH), luteinizing hormone (LH), and thyroid- stimulating hormone (TSH), and reduced antioxidant vitamins in polycystic ovarian syndrome patients.

Elevated oxidative stress and hormonal imbalance have been suggested to associate with polycystic ovarian syndromes (PCOS), a causal factor for unsuccessful pregnancy outcomes and other associated complications in women. The aim of this study was to compare the oxidative stress markers and different relevant hormones between pregnant women with and without PCOS. The levels of malondialdehyde (MDA), insulin, follicle- stimulating hormone (FSH), luteinizing hormone (LH), thyroid-stimulating hormone (TSH), vitamin A and vitamin C were measured in 80 pregnant women with PCOS and 80 healthy pregnancies. The mean MDA and insulin levels were significantly elevated in pregnant women with PCOS compared to healthy controls (1.98±0.07 vs. 1.06±0.02 nmol/mL and 11.15±0.25 vs. 6.67±0.25 mIU/L, respectively with p<0.001 for both). Compared to healthy controls, the mean concentrations of FSH (3.65±0.16 vs. 1.75±0.10 IU/L) and LH (15.67±0.63 vs. 3.65±0.16 IU/L) were significantly higher in pregnant women with PCOS, p<0.001 for both comparisons. Similarly, the concentration of serum TSH was also higher in PCOS cases compared to controls (2.79±0.22 vs. 2.34±0.06, p=0.048). In contrast, the levels of vitamin A and C were lower in PCOS cases compared to healthy pregnancy group, 0.45±0.01 vs. 1.05±0.01 and 0.26±0.01 vs. 0.53±0.02, respectively with p-values <0.001 for both comparations. In conclusion, in PCOS cases, serum MDA, insulin, FSH, LH and TSH levels were found to be elevated while the levels of antioxidant vitamins were lower compared to healthy pregnant women. Unusual hormonal imbalance and increase of oxidative stress markers during the pregnancy might be important to establish the PCOS diagnosis.

The Effect of Estetrol/Drospirenone on Ovarian Function Is Similar to a Well-Established Combined Oral Contraceptive: Results From a Phase 2 Study

Background: Combined oral contraceptives (COCs) often contain ethinylestradiol (EE), an estrogen known to be associated with several side effects including venous thromboembolism. Estetrol (E4) is a native estrogen synthesized by the human fetal liver during pregnancy. Results from a phase 2 dose-finding study showed that E4 15 mg in combination with drospirenone 3 mg (E4/DRSP) resulted in a good bleeding profile and cycle control. Here, we present phase 2 results showing the effect of E4/DRSP on ovarian function. Study Design: A single-center, randomized, open-label, parallel study was conducted in healthy young volunteers with proven ovulatory cycles. Study subjects received either E4 15 mg/DRSP 3 mg (n=41) or EE 20 µg/DRSP 3 mg (n=41) in a 24/4-day regimen for three consecutive cycles. Both in cycle 1 and 3, serum follicle-stimulating hormone (FSH) and luteinizing hormone (LH), estradiol and progesterone levels were determined, and follicular size and endometrial thickness were measured every three days using transvaginal ultrasound. Ovarian function was assessed using the Hoogland score, which considers follicular size and estradiol/progesterone levels. Return of ovulation was determined after treatment cessation. Safety and tolerability were assessed by monitoring adverse events (AEs), vital signs, physical and gynecological examination, clinical laboratory parameters, 12-lead electrocardiogram and echocardiogram. Results: No ovulations were reported during the use of E4/DRSP, while three ovulations occurred in two subjects in the EE/DRSP group. In both groups, most participants had no ovarian activity according to the Hoogland score. In cycle 1, Hoogland scores and follicular diameters were similar in both groups. In cycle 3, these parameters were slightly less suppressed in the E4/DRSP group when compared to EE/DRSP. While mean FSH and LH concentrations were less inhibited by E4/DRSP, mean estradiol and progesterone concentrations and endometrial thickness were similarly suppressed in both groups. Return of ovulation occurred on average 15.5 days after discontinuation of E4/DRSP intake. The number of frequently reported AEs considered to be related to study medication was similar for both treatment groups except for breast pain (11 subjects in the E4/DRSP group versus 4 subjects with EE/DRSP). Most related AEs were of mild or moderate intensity. Three subjects discontinued due to an AE, one with E4/DRSP (severe stress, emotional lability), and two with EE/DRSP (emotional lability, depressed mood). Other safety assessments did not show significant abnormalities. No serious AEs were reported. Conclusions: The combination of E4 15 mg and DRSP 3 mg results in adequate ovulation inhibition and ovarian function suppression, which is similar to a well-established COC containing EE/DRSP. E4/DRSP is considered safe and well-tolerated.

Intravenous infusion of kisspeptin increased serum luteinizing hormone acutely and decreased serum follicle stimulating hormone chronically in prepubertal bull calves

Kisspeptin (KP) is a hypothalamic neuropeptide that stimulates the secretion of gonadotropin releasing hormone. To determine the acute and chronic effects of KP on serum concentrations of luteinizing hormone (LH) and follicle stimulating hormone (FSH), prepubertal bull calves [12 ± 1 (SD) weeks of age; 96.5 ± 14.5 kg BW] were administered one of four treatments [0.0 (control; CON), 0.125 (L-KP), 0.25 (M-KP), or 0.5 (H-KP) μg of KP/kg BW/hour] by intravenous infusion for 76 h. Blood samples were collected every 15 min for the first (acute; 1–6 h; Day 1) and last (chronic; 71–76 h; Day 4) 6 h of the intravenous infusions. Serum concentrations of LH and FSH were determined by radioimmunoassay. For each day, effects of treatment, time, and interactions on LH and FSH concentrations and pulse parameters were analyzed using procedures for repeated measures with JMP Software (SAS Inst. Inc., Cary, NC). There was a treatment effect (P = 0.002) and a treatment × time interaction during Day 1 (P = 0.02) such that LH concentrations were greatest following administration of all doses of KP when compared to CON. However, there was no treatment effect (P = 0.57) or a treatment × time interaction during Day 4 (P = 0.20) on serum LH concentrations. There was a treatment by day interaction (P = 0.02) on mean serum FSH concentrations. Most notably, on Day 4 mean serum FSH concentrations during intravenous infusion of M-KP and H-KP doses were less than that of CON. There was a treatment by day interaction (P = 0.0054) on FSH pulse amplitude concentrations, such that intravenous infusion of all doses of KP on Day 4 decreased FSH pulse amplitudes. In conclusion, acute infusion of KP increased LH concentrations and chronic infusion of KP decreased FSH concentrations. Despite the potential suppression of the hypothalamic–pituitary–gonadal axis with chronic infusion of KP, there are likely applications of KP, KP analogs, or KP receptor agonists to hasten the onset of puberty in livestock.

Acquired Hypogonadotropic Hypogonadism (AHH) in Thalassaemia Major Patients: An Underdiagnosed Condition?

IntroductionIn males, acquired hypogonadotropic hypogonadism (AHH) includes all disorders that damage or alter the function of gonadotropin-releasing hormone (GnRH) neurons and/or pituitary gonadotroph cells. The clinical characteristics of AHH are androgen deficiency and lack, delay or halt of pubertal sexual maturation. AHH lead to decreased libido, impaired erectile function, and strength, a worsened sense of well-being and degraded quality of life (QOL).Patients and methodsWe studied 11 adult men with thalassemia major (TM) aged between 26 to 54 years (mean ± SD: 34.3 ± 8.8 years) with AHH. Twelve age- and sex-matched TM patients with normal pubertal development were used as a control group. All patients were on regular transfusions and iron chelation therapy. Fasting venous blood samples were collected two weeks after transfusion to measure serum concentrations of IGF-1, free thyroxine (FT4), thyrotropin (TSH), cortisol, luteinizing hormone (LH), follicle stimulating hormone (FSH), total testosterone (TT), prolactin and estradiol (E2), glucose, urea, creatinine and electrolytes (including calcium and phosphate). Liver functions and screening for hepatitis C virus seropositivity (HCVab and HCV-RNA) were performed. Iron status was assessed by measuring serum ferritin levels, and evaluation of iron concentrations in the liver (LIC) and heart using MRI- T2*. Bone mineral density was measured at the lumbar spine (L1–L4) for all patients with AHH by dual energy X-ray absorptiometry (DXA) using Hologic QDR 4000 machine.ResultsThe mean basal serum LH and FSH concentrations in AHH patients were 2.4 ± 2.2 IU/L and 1.2 ± 0.9 IU/L respectively; these, values were significantly lower compared to the control group. Semen analysis in 5 patients with AHH showed azoospermia in 3 and oligoasthenozoospermia in 2. The percentage of patients with serum ferritin level >2000 ng/ml (severe iron load) was significantly higher in AHH patients compared to controls, 5/11 (45.4 %) versus1/12 (8.3%), p=0.043. Heart iron concentrations (T2* values) were significantly lower in AHH patients compared to controls (p=0.004). Magnetic resonance imaging in the 3 azoospermic patients revealed volume loss and reduction of pituitary signal intensity. Heart T2* values were significantly reduced in the AHH group vs. the controls (p=0.004). On the other hand, liver iron concentration (mg/g dry weight) was not different between the two groups of TM patients. Using DXA, 63.6 % (7/11) of patients with AHH were osteoporotic, and 36.3 % (4/11) were osteopenic.ConclusionsIn this cohort of thalassemic patients iron overload and chronic liver disease appear to play a role in the development of AHH. Treatment of AHH in TM patients is a vital and dynamic field for improving their health and QOL. Early identification and management of AHH are very crucial to avoid long-term morbidity, including sexual dysfunction and infertility. Therapy aims to restore serum testosterone levels to the mid–normal range. Many exciting opportunities remain for further research and therapeutic development.

Association between follicle-stimulating hormone receptor polymorphisms and reproductive parameters in young men from the general population

Follicle-stimulating hormone (FSH) regulates gametogenesis through binding to its receptor (FSHR). In women, the Thr307Ala and Asn680Ser polymorphisms in the FSHR gene affect reproductive function, but it is not clear whether they have any impact on spermatogenesis and have mainly been investigated in infertile men of varying ages. The aim of the present study was therefore to examine whether these genetic variants of the FSHR influence reproductive parameters in men from the general population. Men aged 17-20 years (n=313) were genotyped. All men provided a semen sample and a blood sample for hormonal measurements and DNA extraction. They underwent a medical examination and analyses of possible associations between Thr307Ala and Asn680Ser polymorphisms and hormonal and sperm parameters were subsequently carried out. Men homozygous for Thr307/Asn680 had a lower mean serum FSH concentration (3.07 vs. 3.65 IU/l, P=0.009), and higher mean serum estradiol (94.0 vs. 86.1 pmol/l, P=0.001), sex hormone-binding globulin (33.6 vs. 31.3 nmol/l, P<0.0001), and total testosterone (19.1 vs.17.9 nmol/l, P<0.0001) concentrations compared with men with other genotypes. In addition, sperm concentrations (71.9 × 10 vs. 70.8 × 10/ml, P=0.040) and the total sperm counts were higher (212 × 10 vs. 206 × 10, P<0.0001) and their testes volumes were larger (left: 11.5 vs. 11.0 ml, P<0.0001; right: 12.4 vs. 11.6 ml, P=0.002). As in women, the results from the present study indicate that variants of the FSHR influence reproductive parameters in men.

Impacto da embolização arterial do leiomioma uterino no volume uterino, diâmetro do mioma dominante e na função ovariana

To evaluate the impact of uterine artery embolization (UAE) on uterine volume (UV), greater myoma diameter (GMD) and ovarian function three months after the procedure, by transvaginal pelvic ultrasonography (TVPUS) and by the determination of follicle-stimulating hormone (FSH). Thirty patients with leiomyomas were submitted to UAE. TVPUS and FSH determination were performed before and three months after UAE. UV was determined in cm³, GMD in cm and FSH in IU/mL. Data are reported as as mean standard deviation (SD) and were analyzed statistically by the nonparametric Mann-Whitney test. Twenty-nine patients were analyzed. Before UAE, mean UV was 402.4 165.9 cm³ and GMD was 5.9 2.1 cm. After UAE, mean UV was 258.9 118.6 cm³ and GMD was 4.6 1.8 cm. Mean FSH concentration was 4.9 3.5 IU/mL before UAE and 5.5 4.7 IU/mL after UAE, with p=0.5. There was a 35% reduction of UV and a 22% reduction of GMD, with no changes in FSH values after three months. The procedure significantly reduced UV and GMD but did not cause a significant increase in FSH levels, thus causing no changes in ovarian function.

Variation of plasma INH B, ACT A and FSH concentrations during an estrus cycle in Dazu black goat and Sannen dairy goat

To study the relationship between the concentrations of INH B (Inhibin B), ACT A (Activin A), and FSH (Follicle stimulating hormone) in blood plasma and fecundity, Dazu black goat with high productivity and Sannen dairy goat with low productivity were used as experiment objects in this research. The concentrations of INH B, ACT A, and FSH in blood plasma were measured by enzyme-linked immunosorbent assay (ELISA) in order to study the secretion rule of INH B, ACT A, and FSH during an estrus cycle of two goat breeds. The results indicated that the secretion of FSH showed a positive correlation with ACT A and a negative correlation with INH B. The mean concentration of FSH in Dazu black goat was higher than that in Sanen dairy goat during a estrous cycle. However, during the time from obviously estrus to ovulation, the mean concentration of FSH in Dazu black goat was significantly higher than that in Sannen dairy goat (0.01<P<0.05). These results showed that during an estrus cycle, the differences in INH B, ACT A, and FSH might be the reason for fecundity differences. Activin A might not be responsible for the number of eggs ovulated of goats. The main effect of ACT A may be extention of follicular stage. Inhibin B indirectly influences ovulation by regulation of FSH level.

Circulating concentrations of ovarian steroids and follicle-stimulating hormone (FSH) in ewes with 3 or 4 waves of antral follicle emergence per estrous cycle

The mechanism governing the number of follicle-stimulating hormone (FSH) peaks and emerging follicular waves in ruminants remains unknown. The main purpose of the present study was to examine the relationships between progesterone (P(4)) levels, circulating concentrations of FSH and antral follicular development throughout the interovulatory interval in sheep. We retrospectively analyzed and compared daily serum concentrations of (P4), FSH and estradiol (E2) obtained in cyclic (November-December) Western White Face ewes (Columbia×Rambouillet) that had 3 (n=10) or 4 (n=19) follicular waves per estrous cycle. Follicular growth was monitored in all animals by daily transrectal ultrasonography. Mean P(4) concentrations were greater (p<0.05) in sheep with 4 waves per cycle compared to their counterparts with 3 waves of follicular growth. The ewes with 3 waves exceeded (p<0.05) animals with 4 follicular waves in mean serum FSH concentrations on days 0-2, 6, 7, 9-11, 14 and 15 post-ovulation. Animals with 4 follicular waves exceeded (p<0.05) the ewes with 3 waves in mean serum E(2)> concentrations on days - 1, 2 and 10 of the estrous cycle studied (day 0=ovulation). The present results are supportive of the notion that luteal P(4) is an important endocrine signal, which controls the periodicity of FSH peaks and the number of emerging follicular waves in cyclic ewes.

Suppression of Follicle Wave Emergence in Cyclic Ewes by Supraphysiologic Concentrations of Estradiol-17beta and Induction with a Physiologic Dose of Exogenous Ovine Follicle-Stimulating Hormone1

Follicle waves are preceded by follicle-stimulating hormone (FSH) peaks in ewes. The purpose of the present study was to see whether estradiol implant treatment would block FSH peaks to create a model in which the effect of the timing and mode of FSH peaks could be studied by ovine FSH (oFSH) injection. In Experiment 1, 10 ewes received estradiol-17beta implants on Day 4 after ovulation (Day 0, day of ovulation); five ewes received large implants, and five ewes received small implants. Five control ewes received empty implants. In Experiment 2, 12 ewes received large implants on Day 4. On Day 9, six ewes received oFSH twice, 8 h apart (0.5 microg/kg; s.c.). Implants were left in place for 10 days in both experiments. In both studies, ovarian ultrasonography and blood sampling was done daily. In Experiment 1, estradiol concentrations were significantly higher in ewes with large implants (10.4 +/- 0.7 pg/ml) compared with controls (3.9 +/- 0.7 pg/ml) and ewes with small implants (5.4 +/- 0.7 pg/ml; P < 0.001). A significant reduction was found in mean FSH peak concentration (31%; P < 0.05) and FSH peak amplitude (45%; P < 0.05) in ewes with large implants compared with controls. Mean and basal FSH concentrations were unaffected by the large implants. The large implants halted follicle-wave emergence between Day 0 and 8 after implant insertion. The small follicle pool (2-3 mm in diameter) was unaffected by the large implants. When oFSH was injected into ewes with large implants, a follicle wave emerged 1.5 +/- 0.5 days after injection; however, in ewes given saline alone, a follicle wave emerged 4.8 +/- 0.8 days after injection (P < 0.01). We concluded that truncation of FSH peaks by estradiol implants prevented follicle-wave emergence, but injection of physiologic concentrations of oFSH reinitiated follicle-wave emergence.

Relationship of Hormonal Parameters to Sperm Production in Patients with Varicocele

Idiopathic varicocele is a one of the all too often organic causes of male infertility and may can affect hormonal and spermatogenic function of the testis. We demonstrated relationships of hormonal parameters to sperm production on follicle-stimulating hormone (FSH), (LH) and testosterone blood concentrations to sperm production. The investigations involved a total of 329 patients with varicocele, at aged from 20 to 48 years, mean age 28.76 ± 0.66 years, divided into three groups: group I – patients with varicocele dextra; group II – patients with varicocele sinistra; and group III – patients with varicocele bilateralis. We established in our investigations that in 65.35% of cases the varicocele was attended coupled by with some disorders in the fertilizing ability, included including oligospermia Gr I-II (groups I and II) in 41.33% of cases, oligospermia (Gr.II-IIIgroups II and III) in 15.5% of cases and azoospermia in 8.52% of cases. In 56.83% of cases, the low sperm concentration was attended by decreasedcoupled with reduced sperm motility and velocity. Our data did not demonstrated a statistically significant increase in blood plasma T testosterone and we noted no significant correlation between the magnitude of the change in serum androgen and improvements in sperm concentration or total sperm motility per ejaculate in patients with varicocele. No significant correlations were noted in mean blood LH and FSH concentrations in patients with varicocele and in controls group.

Targeting FSH in androgen-independent prostate cancer: abarelix for prostate cancer progressing after orchiectomy

Objectives To determine the efficacy of the gonadotropin-releasing hormone antagonist abarelix in patients with androgen-independent prostate cancer progressing after orchiectomy and to measure its effect on serum follicle-stimulating hormone (FSH). Methods Sixteen patients with prostate cancer progressing after orchiectomy received abarelix-depot 100 mg by intramuscular injection on days 1, 15, and 29 and then every 28 days for up to 24 weeks (52 weeks in patients who met the criteria for a prostate-specific antigen [PSA] response after 24 weeks). PSA response was the primary endpoint and was defined as a 50% reduction confirmed 4 weeks later. The time to progression and effect of therapy on serum FSH were secondary endpoints. Results No patient met the criteria for a PSA response. Five patients (31%, 95% confidence interval 11% to 58%) experienced confirmed reductions in the PSA level ranging from 9.3% to 31.8%. At the end of the six cycles of therapy, 6 patients remained stable without PSA progression or other signs of disease progression. The median time to progression was 12 weeks (95% confidence interval 6 to 18). The mean serum FSH concentration declined after 4 weeks of study treatment by nearly 90% from a baseline of 45.1 IU/L (95% confidence interval 34.0 to 56.2) and remained suppressed throughout the observation period. Treatment was well tolerated, with one grade 3 allergic reaction. Conclusions Treatment with abarelix in patients with androgen-independent prostate cancer after orchiectomy results in marked reduction in circulating FSH. None of the patients met the PSA response criteria; nonetheless, minor reductions in serum PSA were observed in 5 of 16 patients.

Influence of estradiol, progesterone, and nutrition on concentrations of gonadotropins and GnRH receptors, and abundance of mRNA for GnRH receptors and gonadotropin subunits in pituitary glands of beef cows.

Nutritionally induced anovulatory cows (n = 28) were used to determine the effect of steroids on regulation of synthesis and secretion of gonadotropins. Anovulatory cows were ovariectomized and received intravaginal inserts containing estradiol (E2), progesterone (P4), E2 and P4 (E2P4), or a sham intravaginal insert (C) for 7 d. Concentrations of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were quantified in serum and E2 and P4 were quantified in plasma. Cows were exsanguinated within 1 to 2 h after removal of intravaginal inserts and pituitary glands were collected and stored at -80 degrees C until messenger ribonucleic acid (mRNA) for gonadotropin-releasing hormone receptor (GnRH-R) and gonadotropin subunits, pituitary content of GnRH-R, and LH and FSH were quantified. Pituitary glands from five proestrous cows were harvested to compare gonadotropin characteristics between ovariectomized, anovulatory cows and intact cows. Plasma concentrations of E2 were greater (P < 0.05) in E2-treated cows than in sham-treated cows. Concentrations of P4 were greater (P < 0.05) in cows treated with P4 than in sham-treated cows. Mean serum concentrations of LH and FSH were not significantly influenced by steroid treatments. However, frequency of LH pulses of ovariectomized, nutritionally induced anovulatory cows was increased (P < 0.05) by treatment with E2 and amplitude of LH pulses was greater (P < 0.05) in cows treated with E2 or P4 than in cows treated with E2P4 or sham-treated. Quantity of mRNA for LHbeta in the pituitary gland was greater when cows were treated with P4. Concentrations of LH in the pituitary gland were not affected by steroid treatments; however, pituitary concentrations of FSH were less (P < 0.1) in E2 cows than in sham-treated cows. The number of GnRH-R was increased (P < 0.05) in cows treated with E2, but P4 treatment did not influence the number of GnRH-R. Abundance of mRNA for GnRH-R, common alpha-subunit, and FSHbeta were not affected by treatments. Pituitary concentrations of LH were greater (P < 0.05) and concentrations of FSH were less (P < 0.05) in proestrous cows than in ovariectomized, anovulatory cows treated with or without steroids. Abundance of mRNA for GnRH-R, common alpha-subunit, LHbeta and FSHbeta were similar for proestrous and anovulatory cows. We conclude that treatment of nutritionally induced anovulatory cows with progesterone and estradiol may cause pulsatile secretion of LH.

Ovarian follicular dynamics and endocrine profiles in Polwarth ewes with high and low body condition

AbstractIn this investigation we tested the hypothesis that static body condition (BC) of the ewe affects oestradiol and FSH with implications for subsequent follicular growth and turn-over. Sixteen Polwarth ewes were selected from a flock according to their BC score (scale: 1 emaciated; 5 obese). High BC (HBC) ewes (no. = 8) had a BC score of 4·1 (s.e. 0·1) and low BC (LBC) ewes (no. = 8) had a BC score of 1·9 (s.e. 0·1). Daily ultrasound examinations were performed and blood samples for progesterone, oestradiol and follicle-stimulating hormone (FSH) determination were collected. All HBC ewes (8/8) exhibited three waves of follicular development, while four LBC ewes (4/8) had two waves and the other four (4/8) had three waves of follicular development (P ≤ 0·05) during the interovulatory period. Overall, the emergences of 33 out of 44 follicular waves were preceded by significant increases in FSH concentrations. Maximum FSH concentrations were detected 0·9 ± 0·2 days before wave emergence. Oestradiol concentrations increased significantly during the growing phase in 38 out of 44 large follicles. A negative correlation between oestradiol and FSH was observed in HBC ewes. A similar inhibitory effect of oestradiol on FSH was observed in LBC ewes, irrespective of whether they developed two or three follicular waves. However, a longer period with high FSH was needed to promote the emergence of the second follicular wave in two-wave LBC ewes. Four HBC ewes had twin ovulations but no LBC ewes did (P ≤ 0·05). In HBC ewes, the follicular phase was characterized by lower oestradiol (6·5 (s.e. 1·0) pmol/l) but higher mean FSH concentrations (2·4 (s.e.0·4) μg/l) than in LBC ewes (8·9 (s.e. 1·2) pmol/l and 2·0 (s.e. 0·3) μg/l, respectively; P ≤ 0·05). The present results suggest that BC influences the pattern of follicular dynamics through changes in the endocrine milieu. Higher FSH concentrations during the follicular phase in HBC ewes, which allowed an extended period of follicular recruitment from a significantly larger pool of small antral follicles could explain the higher ovulation rate observed in this group.

Bone mass, gonadal function and biochemical assessment in young men with trisomy 21

Objective: The objective of the study was to find out whether biochemical and hormonal profile of sexual function and mineral metabolism are related to low bone mass in young men with Down syndrome. Study design: Eleven young men with trisomy 21 (mean age 26.45 years) and 12 healthy university students of similar age, participated in the study. The bone mineral density (BMD) of the lumbar vertebrae was measured in posteroanterior (PA) projection. Sexual development was assessed by clinical examination. The levels of follicle stimulating hormone (FSH), luteinizing hormone (LH), testosterone, dehydroepiandrosterone sulfate (DHEA-S), 17-OH progesterone and parathormone (PTH) were measured accordingly by radioimmunoassay. Serum calcium (Ca) and phosphate (P) as well as fasting urinary Ca and hydroxyproline (OHP) were also measured. Results: BMD in DS patients was significantly lower (P<0.001) compared to their control counterparts. No significant differences were observed in mean concentrations of FSH, testosterone and DHEA-S, while LH and 17-OH progesterone levels were significantly higher in DS compared to control group (P<0.01 and <0.05, respectively). Serum Ca and P and urine Ca/Creat ratio did not differ between groups. OHP/Creat ratio was significantly higher in DS patients. PTH levels were extremely low (1pmol/l) in two patients. Conclusions: The findings of this study show decreased bone mass in subjects with DS. Factors, possibly related to low bone mass, are some degree of hypogonadim, hypotonia, low muscular strength and immobility. The findings suggest further research on the biochemistry and endocrinology of bone metabolism in patients with trisomy 21.

Effect of dioxin on ovarian function in the cynomolgus macaque ( M. fascicularis)

Ovarian function was evaluated in mature female cynomolgus macaques 443 to 625 days following a single oral exposure (1, 2, or 4 μg/kg BW) to 2,3,7,8-tetrachlorodibenzo- p-dioxin (TCDD). Urinary estrone conjugates (E1C), pregnanediol-3-glucuronide (PdG), and follicle stimulating hormone (FSH) were measured. Three of four animals in the high dose group had no evidence of menstrual cycles while animals in the low and medium dose groups plus one from the high dose group had cycles that were similar to those of control animals. The noncycling animals had baseline E 1C concentrations without ovulatory midcycle peaks and monotonic PdG profiles. Mean FSH concentrations during the midfollicular phase of the medium dose group and during the entire cycle of the high dose group were elevated compared to those of the control group and the endometria of the noncycling animals were inactive. These data demonstrate that a single exposure of 4 μg/kg BW TCDD leads to long-term adverse effects on ovarian function in primates.

Day 3 serum inhibin B and FSH and age as predictors of assisted reproduction treatment outcome.

Recent reports investigating the value of basal inhibin B determination as a predictor of ovarian reserve and assisted reproduction treatment have led to discordant results. This study was undertaken to further assess the relative power of day 3 inhibin B and follicle stimulating hormone (FSH) (defined before treatment) and the woman's age both as single and combined predictors of ovarian response and pregnancy in an in-vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) programme. A total of 120 women undergoing their first cycle of IVF or ICSI was included. Forty consecutive cycles cancelled because of poor follicular response were initially selected. As a control group, the nearest completed IVF/ICSI cycles before and after each cancelled cycle (i.e. the closest cycles in temporal relationship to the index cycle) were used. Mean age and basal FSH concentrations were significantly higher in the cancelled than in the control group (P: < 0.01 and P: < 0.001 respectively), whereas basal inhibin B was significantly higher in the latter (P: < 0.05). The association of basal FSH (with an accuracy or predictive value of ovarian response of 79%) with cancellation rate was significant, independent of, and stronger than the effects of age and inhibin B (P: < 0.05). Any two or all three of these variables studied did not improve the predictive value of FSH alone. Woman's age was the only variable independently associated with pregnancy rate. It is concluded that the stronger predictors of success in patients undergoing their first IVF/ICSI treatment cycle are age and basal FSH rather than inhibin B. Basal FSH concentration was a better predictor of cancellation rate than age, but age was a stronger predictor of pregnancy rate.

Gonadal function in young women with Down syndrome

Objective: Investigations suggest an increased incidence of gonadal dysfunction in patients with Down syndrome. New features, Alzheimer disease and osteoporosis emerge in these individuals. Therefore, hormonal investigation in persons with Down syndrome is pursued. Methods: Thirteen females with trisomy 21 (23.65±3.23 years old) participated in the study. Ultrasound studies were performed to explore the internal genitals. Blood samples were taken for the determination of follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), prolactin (PRL), dehydroepiandrosterone sulfate (DHEA-S), testosterone (T) and 17-hydroxyprogesterone (17-OHP). Results: The patients were at stage V of sexual development. Ultrasonography demonstrated normal uterine and ovarian size and endometrial thickness as well. The ovaries of all patients contained follicles of normal distribution and various sizes. The mean concentrations of FSH, DHEA-S and E2 were normal. The level of PRL was significantly higher than that of the controls, but within the normal lab range. The levels of LH, T and 17-OHP were significantly elevated, compared to those of the control group ( P<0.05, P<0.01, P<0.001, respectively). Conclusions: Our data produce new information on the gonadal function of Down syndrome women. Specific studies on pituitary-gonadal and pituitary-adrenal axis function are needed.

Median eminence lesions reveal separate hypothalamic control of pulsatile follicle-stimulating hormone and luteinizing hormone release.

The effects of hypothalamic lesions designed to destroy either the anterior median eminence (ME) or the posterior and mid-ME on pulsatile release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) were determined in castrated male rats. In sham-operated animals, mean plasma FSH concentrations rose to peak at 10 min after the onset of sampling, whereas LH declined to a nadir during this time. In the final sample at 120 min, the mean FSH concentrations peaked as LH decreased to its minimal value. In rats with anterior ME lesions, there was suppression of LH pulses with continuing FSH pulses in 12 of 21 rats. On the other hand, in animals with posterior to mid-ME lesions, 3 out of 21 rats had elimination of FSH pulses, whereas LH pulses were maintained. Fifteen of 42 operated rats had complete ME lesions, and pulses of both hormones were abolished. The remaining 12 rats had partial ME lesions that produced a partial block of the release of both hormones. The results support the concept of separate hypothalamic control of FSH and LH release with the axons of the putative FSH-releasing factor (FSHRF) neuronal system terminating primarily in the mid- to caudal ME, whereas those of the LHRH neuronal system terminate in the anterior and mid-median eminence. We hypothesize that pulses of FSH alone are mediated by release of the FSHRF into the hypophyseal portal vessels, whereas those of LH alone are mediated by LHRH. Pulses of both gonadotropins simultaneously may be mediated by pulses of both releasing hormones simultaneously. Alternatively, relatively large pulses of LHRH alone may account for simultaneous pulses of both gonadotropins since LHRH has intrinsic FSH-releasing activity.

Concentrations of gonadotropins, estradiol and progesterone in sows selected on an index of ovulation rate and embryo survival.

The objective of this study was to determine concentrations of follicle stimulating hormone (FSH), luteinizing hormone (LH), progesterone (P4) and 17beta-estradiol (E2) in sows from a line selected on an index which emphasized ovulation rate (Select) and from a control line. A further classification of the sows in each line was made according to the estimated number of ovulations during an estrous cycle. Sows in the Select line were ranked into a high (HI) or low group (LI) when their estimated number of ovulations were 25 or more and 14 to 15, respectively. Sows of the control line were classified into groups as high (HC) or low (LC) when the estimated values for ovulation rate were 14-15 and 8-9 ovulations, respectively. Blood samples were collected every 12 h during a complete estrous cycle and samples were analyzed for concentrations of FSH and LH. Samples collected every 24 h were assayed for P4 and E2. Mean concentrations of FSH, LH, P4 and E2 did not differ (P > 0.10) between lines or between HI and LI or HC and LC groups. Selection of pigs for ovulation rate and embryonal survival did not affect concentrations of FSH, LH, P4 and E2 in sows during the estrous cycle.