Luteal Phase Levels Research Articles

Blood glucose variance measured by continuous glucose monitors across the menstrual cycle

Past studies on how blood glucose levels vary across the menstrual cycle have largely shown inconsistent results based on limited blood draws. In this study, 49 individuals wore a Dexcom G6 continuous glucose monitor and a Fitbit Sense smartwatch while measuring their menstrual hormones and self-reporting characteristics of their menstrual cycles daily. The average duration of participation was 79.3 ± 21.2 days, leading to a total of 149 cycles and 554 phases in our dataset. We use periodic restricted cubic splines to evaluate the relationship between blood glucose and the menstrual cycle, after which we assess phase-based changes in daily median glucose level and associated physiological parameters using mixed-effects models. Results indicate that daily median glucose levels increase and decrease in a biphasic pattern, with maximum levels occurring during the luteal phase and minimum levels occurring during the late-follicular phase. These trends are robust to adjustments for participant characteristics (e.g., age, BMI, weight) and self-reported menstrual experiences (e.g., food cravings, bloating, fatigue). We identify negative associations between each of daily estrogen level, step count, and low degrees of fatigue with higher median glucose levels. Conversely, we find positive associations between higher food cravings and higher median glucose levels. This study suggests that blood glucose could be an important parameter for understanding menstrual health, prompting further investigation into how the menstrual cycle influences glucose fluctuation.

P-614 Endometrial preparation: effect of estrogen levels before the embryo transfer on the live birth rate from 14825 freezing-all cycles

Abstract Study question Is there a difference in live birth rate during discrepant estrogen levels before the embryo transfer following either hormone replacement therapy (HRT) or natural cycle(NC)? Summary answer The higher estrogen level on the day before embryo transfer may reduce the live birth rate in either HRT or NC. What is known already The endometrial preparation of frozen embryo transfer cycle is to synchronize of endometrium and embryo under the condition of exogenous estrogen and progesterone drugs in HRT or follicle monitoring in NC. Estrogen is crucial and different estrogen levels could imply variations on endometrial preparation. Information on the effect of discrepant estrogen levels before the embryo transfer on reproductive outcomes of women undergoing freezing-all cycles is scarce. Study design, size, duration Retrospective cohort study including 14825 first frozen embryo transfers following IVF/ICSI undergoing freezing-all cycles from January 2016 to December 2020. A total of 12305 (83.0%) patients received NC while 2520 (17.0%) received HRT. Participants/materials, setting, methods Effect of estrogen levels on live birth rates, stratifified by deciles and ROC to determine the cutoff values for estrogen level on the day before embryo transfer.Multivariable logistic regression analysis was performed to adjust for confounders. Main results and the role of chance The live birth rate was 44.7% and 52.4% in HRT and NC respectively. The live birth rate of HRT began to decline when the estrogen level was P60 in the deciles which the cut-off values of ROC was closed with the estrogen level was 891.6 pg/ml. The lower level of estrogen on the day before embryo transfer in HRT corresponds to a higher live birth rate（51.4% vs 32.9%）.The cut-off values of ROC in NC was statistically different with the estrogen level was 194.4 pg/ml. The lower level of estrogen on the day before embryo transfer in NC corresponds to a higher live rate（53.0% vs 48.6%）.After adjusting the possible confounding factors by multivariate logistic regression, it was found that the estrogen level on the day before embryo transfer in HRT and NC was the independent influencing factor of live birth rate with the OR of 0.57 (0.47,0.68) and 0.82 (0.74,0.90), respectively. Limitations, reasons for caution The greatest limitation of this study is its retrospective study. On the other hand, this study was performed using non-PGT cycle, although this is unlikely to affect the results,we cannot exclude the possibility that euploid embryo responds differently to endometrial state in comparison to aneuploid embryo. Wider implications of the findings In freezing-all cycles, the higher estrogen level on the day before embryo transfer may reduce the live birth rate in either HRT or NC. Clinicians should pay attention to the control of estrogen level in luteal phase. Trial registration number Nona

Emotion-induced brain activation across the menstrual cycle in individuals with premenstrual dysphoric disorder and associations to serum levels of progesterone-derived neurosteroids

Premenstrual dysphoric disorder (PMDD) is a debilitating disorder characterized by severe mood symptoms in the luteal phase of the menstrual cycle. PMDD symptoms are hypothesized to be linked to an altered sensitivity to normal luteal phase levels of allopregnanolone (ALLO), a GABAA-modulating progesterone metabolite. Moreover, the endogenous 3β-epimer of ALLO, isoallopregnanolone (ISO), has been shown to alleviate PMDD symptoms through its selective and dose-dependent antagonism of the ALLO effect. There is preliminary evidence showing altered recruitment of brain regions during emotion processing in PMDD, but whether this is associated to serum levels of ALLO, ISO or their relative concentration is unknown. In the present study, subjects with PMDD and asymptomatic controls underwent functional magnetic resonance imaging (fMRI) in the mid-follicular and the late-luteal phase of the menstrual cycle. Brain responses to emotional stimuli were investigated and related to serum levels of ovarian steroids, the neurosteroids ALLO, ISO, and their ratio ISO/ALLO. Participants with PMDD exhibited greater activity in brain regions which are part of emotion-processing networks during the late-luteal phase of the menstrual cycle. Furthermore, activity in key regions of emotion processing networks - the parahippocampal gyrus and amygdala - was differentially associated to the ratio of ISO/ALLO levels in PMDD subjects and controls. Specifically, a positive relationship between ISO/ALLO levels and brain activity was found in PMDD subjects, while the opposite was observed in controls. In conclusion, individuals with PMDD show altered emotion-induced brain responses in the late-luteal phase of the menstrual cycle which may be related to an abnormal response to physiological levels of GABAA-active neurosteroids.

Role of allopregnanolone-mediated γ-aminobutyric acid A receptor sensitivity in the pathogenesis of premenstrual dysphoric disorder: Toward precise targets for translational medicine and drug development.

Premenstrual dysphoric disorder (PMDD) can be conceptualized as a disorder of suboptimal sensitivity to neuroactive steroid hormones. Its core symptoms (emotional instability, irritability, depression, and anxiety) are related to the increase of stress sensitivity due to the fluctuation of hormone level in luteal phase of the menstrual cycle. In this review, we describe the emotional regulatory effect of allopregnanolone (ALLO), and summarize the relationship between ALLO and γ-aminobutyric acid A (GABAA) receptor subunits based on rodent experiments and clinical observations. A rapid decrease in ALLO reduces the sensitivity of GABAA receptor, and reduces the chloride influx, hindered the inhibitory effect of GABAergic neurons on pyramidal neurons, and then increased the excitability of pyramidal neurons, resulting in PMDD-like behavior. Finally, we discuss in depth the treatment of PMDD with targeted GABAA receptors, hoping to find a precise target for drug development and subsequent clinical application. In conclusion, PMDD pathophysiology is rooted in GABAA receptor sensitivity changes caused by rapid changes in ALLO levels. Targeting GABAA receptors may alleviate the occurrence of PMDD.

Serum progesterone level in luteal phase improves pregnancy rate in fresh cycles with blastocyst embryo transfer.

To assess the association between serum level of progesterone during stimulation and in the luteal phase with pregnancy rate in a cohort of patients undergoing in vitro fertilization and embryo transfer (IVF-ET) on day 5. Retrospective Cohort Study. Patients: 62 infertile women, aged 24-42 years, undergoing ART at our center from May 2019 to May 2021. Progesterone was evaluated during ovarian stimulation on Day 2, Day 6, and Day 8 of stimulation, day of trigger (P4dhCG), and on the day of blastocyst transfer with 5 days of progesterone supplementation (P4d5+). We also calculated the difference of P4d5+ with P4dhCG. (∆P4). Then we divided the patients into two groups based on progesterone serum levels at P4d5+; <10ng/ml (Group A), ≥10ng/ml (Group B). The Student's t-test was performed for continuous variables; Mann-Whitney's Test and Spearman's Test were used where appropriate for categorical variables. p<0.05 was considered statistically significant. There were positive correlations between βhCG positive with P4d5+ (p<0.001; Rho 0.770) and ∆P4 (p<0.001; Rho 0.703). The pregnancy rate doubled when the serum progesterone level was ≥10ng/ml on the fifth day of progesterone supplementation compared with P4<10ng/ml (44% vs. 21%, respectively). The pregnancy rate was positively correlated with the serum P4 level on the fifth day of progesterone supplementation and with the difference between the serum progesterone level in the Dd5+ / dhCG. A higher pregnancy rate was observed when serum progesterone level on the fifth day of progesterone supplementation was ≥10ng/ml.

Additional luteal support might improve IVF outcomes in patients with low progesterone level in middle luteal phase following a GnRH agonist protocol

Aim The purpose of the study was to explore the efficacy of additional luteal support (ALS) for patients with low progesterone (P4) level in the middle luteal phase. Methods A retrospective study of 1401 women who underwent their first in vitro fertilization (IVF) treatment with a GnRH agonist protocol was analyzed. Patients were divided into five groups according to P4 level in the middle luteal phase (group I>40ng/mL, group II 31–40 ng/mL, group III 21–30 ng/mL, group IV 11–20 ng/mL and group V 0–10 ng/mL. Besides routine luteal support, the group V was offered with additional oral dydrogesterone 10 mg twice daily to HCG test (ALS group). Results After a multiple regression analysis, a similar higher hCG positive rate, clinic pregnancy rate and lower early pregnancy loss rate were achieved in group I and group V. In contrast to group I, group IV demonstrated significant lower HCG positive rate (OR = 0.65 [0.43; 0.99], p = .05), lower clinic pregnancy rate (OR = 0.60 [0.41; 0.88], p < .01) and significant higher early pregnancy loss rate (OR = 1.80 [1.08; 2.99], p = .02). The group III also resulted in significant lower clinic pregnancy rate (OR = 0.56 [0.36; 0.87], p = .01). The live birth rate tended to be higher in group I and group V but without a significant difference. Conclusion Following agonist protocol, additional luteal support might improve IVF outcomes in patients with low serum P4 level in the middle luteal phase.

Peripheral administration of SB223412, a selective neurokinin-3 receptor antagonist, suppresses pulsatile luteinizing hormone secretion by acting on the gonadotropin-releasing hormone pulse generator in estrogen-treated ovariectomized female goats.

Accumulating evidence suggests that KNDy neurons located in the hypothalamic arcuate nucleus (ARC), which are reported to express kisspeptin, neurokinin B, and dynorphin A, are indispensable for the gonadotropin-releasing hormone (GnRH) pulse generation that results in rhythmic GnRH secretion. The aims of the present study were to investigate the effects of peripheral administration of the neurokinin 3 receptor (NK3R/TACR3, a receptor for neurokinin B) antagonist, SB223412, on GnRH pulse-generating activity and pulsatile luteinizing hormone (LH) secretion in ovariectomized Shiba goats treated with luteal phase levels of estrogen. The NK3R antagonist was infused intravenously for 4 h {0.16 or 1.6 mg/(kg body weight [BW]·4 h)} during which multiple unit activity (MUA) in the ARC was recorded, an electrophysiological technique commonly employed to monitor GnRH pulse generator activity. In a separate experiment, the NK3R antagonist (40 or 200 mg/[kg BW·day]) was administered orally for 7 days to determine whether the NK3R antagonist could modulate pulsatile LH secretion when administered via the oral route. Intravenous infusion of the NK3R antagonist significantly increased the interval of episodic bursts of MUA compared with that of the controls. Oral administration of the antagonist for 7 days also significantly prolonged the interpulse interval of LH pulses. The results of this study demonstrate that peripheral administration of an NK3R antagonist suppresses pulsatile LH secretion by acting on the GnRH pulse generator, suggesting that NK3R antagonist administration could be used to modulate reproductive functions in ruminants.

Control and induction of ovulation in cattle

The control and induction of ovulation in cattle are discussed with particular reference to use of progesterone-impregnated coils in heifers and beef cows. Progesterone treatment for 14 days was required to obtain precise onset of oestrus. With 7, 9 or 12 days of progesterone treatment a luteolytic agent in the form of a prostaglandin (PG) or oestradiol benzoate had to be used. Fertility was normal after treatment durations of 7, 9 or 12 days, but fertility after 14-day treatment requires further testing. The progesterone coil was not effective in maintaining luteal-phase levels of progesterone throughout a 12-day treatment and increasing the concentration of progesterone in the coil from 4 to 20% was not effective in elevating the progesterone concentrations in blood. When progesterone concentrations dropped below approximately 1.5 ng/ml the basal level of LH began to rise before removal of the coil. A 2-fold rise in the basal level of LH was observed following the removal of the progesterone coil. This early rise in LH was absent in cows which did not ovulate after they were given a 12-day progesterone treatment and GnRH 24-36 h after removal of coils to induce the main LH peak. Absence of this early rise suggests that frequency and amplitude of episodic LH release were inadequate in the post-partum anovulatory period. Ovariectomy in the early post-partum period was not followed by an abrupt LH release.

Effect of season on hormonal profile and some biochemical parameters at different stages of estrous cycles in Baladi goats

Understanding the seasonal patterns of estrus cycle in caprine is crucial to develop the efficient breeding plans in the subtropics. Thus, the aim of the current research was to evaluate the effects of breeding season on hormonal profile and blood biochemical indices at different stages of estrus cycle in normal breeding or out-of-season breeding in goats. Forty-four Baladi goats were monitored for a period of eight months (July–February). Baladi goats exhibit a normal seasonal breeding (NS) at midsummer and continue through the autumn season (68%), with a considerable percentage of females having estrus signs during out-of-season (OS) period (32%). At the mid and late luteal phases of estrus cycles, the NS breeding group had significantly higher serum progesterone level than that reported in the OS group (p = 0.013 and 0.039, respectively). At the estrus and late luteal phases of estrus cycles, the NS breeding group had significantly higher serum β-estradiol level than that reported in the OS group (p = 0.022 and 0.001, respectively). Compared to the OS group, the NS breeding group had significantly higher serum cholesterol at the mid and late luteal phases of estrus cycle (p = 0.001 and 0.016, respectively), and higher serum glucose level in the early luteal phase of the cycle (p = 0.009). In conclusion, the NS breeding goats had superior progesterone (mid-luteal and late luteal phases) and estradiol (estrus and late luteal phases) profiles than that reported in the OS group. This may indicate specific approaches to maintain the breeding efficiency of goats during the out-of-season period.

Changes in hormones of the hypothalamic-pituitary-gonadal axis in migraine patients

The incidence of migraine is higher in women than in men. Abnormality of the hypothalamus-pituitary-gonadal (HPG) axis is believed to be implicated in the pathogenesis of migraine. The aim of this study was to detect serum hormone levels in the HPG axis of migraineurs and analyze the relationship between the hormone levels and migraine-related clinical characteristics. One hundred and nineteen migraineurs were enrolled. Serum FSH, LH, estradiol, progesterone, testosterone, prolactin and GnRH was detected. Pain intensity and migraine-related disability were evaluated using the visual analogue scale (VAS) and the Migraine Disability Assessment questionnaire (MIDAS). The relationships between sex hormone levels and the VAS score and the MIDAS score were also examined. Progesterone levels in male migraineurs were lower than those in healthy controls (P < .01). In female patients, in the follicular phase, testosterone levels were lower than in healthy controls (P < .01). In the luteal phase, estrogen and testosterone levels (P < .05) were lower than in healthy controls. Progesterone and testosterone levels (P < .01) were lower than in healthy controls in the postmenopausal phase. In male patients, estrogen levels were negatively associated with the MIDAS score (r = −0.602). In female patients, in the follicular phase, estrogen levels were positively correlated with headache duration and VAS score (r = 0.374, r = 0.331, respectively) and negatively related with MIDAS score (r = −0.334). In the luteal phase, estrogen and progesterone levels were negatively correlated with the MIDAS score (r = −0.772, r = −0.464, respectively). The levels of HPG axis hormones were abnormal in migraineurs and were associated with migraine-related clinical characteristics.

Interactive Effects of Dopamine Baseline Levels and Cycle Phase on Executive Functions: The Role of Progesterone.

Estradiol and progesterone levels vary along the menstrual cycle and have multiple neuroactive effects, including on the dopaminergic system. Dopamine relates to executive functions in an “inverted U-shaped” manner and its levels are increased by estradiol. Accordingly, dopamine dependent changes in executive functions along the menstrual cycle have been previously studied in the pre-ovulatory phase, when estradiol levels peak. Specifically it has been demonstrated that working memory is enhanced during the pre-ovulatory phase in women with low dopamine baseline levels, but impaired in women with high dopamine baseline levels. However, the role of progesterone, which peaks in the luteal cycle phase, has not been taken into account previously. Therefore, the main goals of the present study were to extend these findings (i) to the luteal cycle phase and (ii) to other executive functions. Furthermore, the usefulness of the eye blink rate (EBR) as an indicator of dopamine baseline levels in menstrual cycle research was explored. 36 naturally cycling women were tested during three cycle phases (menses–low sex hormones; pre-ovulatory–high estradiol; luteal–high progesterone and estradiol). During each session, women performed a verbal N-back task, as measure of working memory, and a single trial version of the Stroop task, as measure of response inhibition and cognitive flexibility. Hormone levels were assessed from saliva samples and spontaneous eye blink rate was recorded during menses. In the N-back task, women were faster during the luteal phase the higher their progesterone levels, irrespective of their dopamine baseline levels. In the Stroop task, we found a dopamine-cycle interaction, which was also driven by the luteal phase and progesterone levels. For women with higher EBR performance decreased during the luteal phase, whereas for women with lower EBR performance improved during the luteal phase. These findings suggest an important role of progesterone in modulating dopamine-cycle interactions. Additionally, we identified the eye blink rate as a non-invasive indicator of baseline dopamine function in menstrual cycle research.

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A Potential Role for Endoplasmic Reticulum Stress in Progesterone Deficiency in Obese Women.

Obesity in reproductive-aged women is associated with a shorter luteal phase and lower progesterone levels. Lipid accumulation in follicles of obese women compromises endoplasmic reticulum (ER) function, activating ER stress in granulosa cells. We hypothesized that ER stress activation in granulosa-lutein cells (GLCs) would modulate progesterone production and contribute to obesity-associated progesterone deficiency. Pretreatment with an ER stress inducer, tunicamycin or thapsigargin, inhibited human chorionic gonadotropin (hCG)-stimulated progesterone production in cultured human GLCs. Pretreatment of human GLCs with tunicamycin inhibited hCG-stimulated expression of steroidogenic acute regulatory protein (StAR) and 3β-hydroxysteroid dehydrogenase (3β-HSD) messenger RNAs (mRNAs) without affecting expression of cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), as determined by real-time quantitative polymerase chain reaction. Pretreatment with tunicamycin also inhibited hCG-stimulated expression of StAR protein and 3β-HSD enzyme activity in cultured human GLCs, as determined by Western blot analysis and an enzyme immunoassay, respectively, but did not affect hCG-induced intracellular 3',5'-cyclic adenosine monophosphate accumulation. Furthermore, tunicamycin attenuated hCG-induced protein kinase A and extracellular signal-regulated kinase activation, as determined by Western blot analysis. In vivo administration of tunicamycin to pregnant mare serum gonadotropin-treated immature mice prior to hCG treatment inhibited the hCG-stimulated increase in serum progesterone levels and hCG-induced expression of StAR and 3β-HSD mRNA in the ovary without affecting serum estradiol levels or the number of corpora lutea. Our findings indicate that ER stress in the follicles of obese women contributes to progesterone deficiency by inhibiting hCG-induced progesterone production in granulosa cells.

Abstract 1102: miRNAs are key mediators of crosstalk between estrogen and progesterone regulating breast cancer invasiveness

Abstract Even though estrogen receptor (ER)-positive breast tumors are exquisitely sensitive to anti-estrogen therapy, the disease is virtually incurable when it has progressed to ER+ distal metastasis. Therefore a better understanding of regulatory processes in ER+ breast tumor invasiveness is important. Invasive ER+ breast tumors frequently express high levels of the progesterone receptor (PR) isoform A (PR-A), relative to PR-B. We have previously reported that E2 strongly represses in vitro invasiveness below concentrations of E2 corresponding to median plasma and breast tissue levels post-menopause. Progesterone, at concentrations corresponding to postmenopausal levels, completely abrogates inhibition of invasiveness by E2. The ability of progestins to rescue invasiveness from estrogen regulation is exclusively mediated by PR-A. In contrast, at the high concentrations associated with luteal phase and pregnancy levels, progesterone induces invasiveness independent of E2 through PR-B. Interventions that target PR-A are limited by the fact that functional PR-A is needed to protect against E2-induced uterine dysplasia and hyperplasia. In order to attenuate PR-A dependent invasiveness, it is necessary to identify and target mediators of specific cross-talk between E2/ER and progestin/PR-A in the context of hormonal regulation of invasiveness. As micro-RNAs (miRs) are known to play a major role in the actions of E2, we investigated two possible modalities for miRs to mediate this cross talk: (1) Progesterone/PR-A could induce expression of critical miRs that attenuate suppressive effects of E2 on invasiveness; (2) E2-regulated miRs that directly influence invasiveness may be counter-regulated by progesterone/PR-A. Using microarray analysis and quantitative PCR in several ER+ cell lines, we identified five miRs (miR-6805, miR-584, miR-1228, miR-501, and miR-668) that were activated by progestin exclusively by PR-A, but were not regulated by E2. Whereas these miRs could serve as a signature of hyperactive PR-A, loss-of-function studies using miR inhibitors indicated that they did not play a functional role in the ability of PR-A to regulate invasiveness. An additional ten miRs were regulated by E2/ER (activated or repressed), in a manner that was counter-regulated by progestin/PR-A. Two of these miRs (miR-92a, and miR-26b) were identified using miR inhibitors to have a direct role in mediating the ability of progesterone to rescue invasiveness from E2 regulation. In conclusion, this study has provided a potential diagnostic miR signature of hyper-active PR-A and has also identified two miRs that could potentially be targeted to attenuate breast tumor invasiveness supported by progesterone/PR-A. Citation Format: Thomas B. McFall. miRNAs are key mediators of crosstalk between estrogen and progesterone regulating breast cancer invasiveness. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1102.

Effects of season and ovarian status on the outcome of long-term progesterone-based estrus synchronization protocols and ovulatory follicle development in Santa Inês ewes under subtropical conditions

This study set out to investigate the efficiency of long-term estrus synchronization protocols and ovulatory follicle dynamics in ultrasonographically monitored Santa Inês ewes during lengthening (LD; September−October) and shortening photoperiods (SD; April−May), and the transitional period (TP; January). In addition, the influence of ovarian status (e.g., size of antral follicles and/or presence of corpora lutea) at the outset of the estrus synchronization protocols on the ensuing development of ovulatory follicles was examined. Seventy sexually mature Santa Inês ewes were subjected to one of the two estrus synchronization regimens; on Day 0 (random day of the estrous cycle or anovulatory period), the ewes were fitted with an intravaginal progesterone (P4)-releasing (controlled intrauterine drug release [CIDR]) device, which was left in place for 14 days (G-1CIDR, n = 35) or replaced on Day 7 (G-2CIDR, n = 35), and received an intramuscular injection of 10 mg of PGF2α. The ewes allocated to the G-1CIDR group had mean serum P4 concentrations less than 2 ng/mL during the last 4 days of the synchronization protocol. There were no differences (P > 0.05) in mean ovulation rates between the two protocols tested nor among the ewes varying in ovarian status or studied at different times of the year, but ovulations occurred ∼12 hours later in the TP compared with the SD period (P < 0.05). Ovulatory follicles emerged earlier (P < 0.05) in the G-1CIDR group than in the G-2CIDR group (Day 8.3 ± 0.5 vs. 9.2 ± 0.4) and during LD (Day 7.1 ± 0.6) compared with the TP (Day 9.1 ± 0.6) and SD (Day 9.9 ± 0.5 of the protocol). In conclusion, the replacement of CIDR devices prevented the occurrence of lower-than-normal luteal phase levels of P4 at the end of the 14-day estrus synchronization protocol. However, although this procedure and seasonal influences altered certain growth characteristics of ovulatory follicles, there were no effects of these factors on the mean ovulation rate.

Assessment of the reproductive physiology of the potto (Perodicticus potto) through fecal hormone metabolite analyses and trans-abdominal ultrasonography

Potto (Perodicticus potto) reproductive biology has been minimally studied. Noninvasive endocrinology and ultrasonography are proven tools for reproductive assessment in other primates. In this study, we used fecal hormone metabolite analysis to monitor one adult male potto and four females at different life stages. Validated testosterone (T), estrone conjugate (EC), and progesterone (P4) enzyme immunoassays (EIA) were used to assess male testicular function and female ovarian and placental activity. The male excreted mean T concentrations of 4.72 (±1.66) μg/g feces, that did not differ (P > 0.05) over time or when paired with alternate females. Baseline concentrations of EC (range: 47.93-78.81 ng/g feces) and P4 (range: 2.29-12.46 μg/g feces) differed among adult females. Follicular phases averaged 9.1 days (±3.43, n = 30 phases), whereas luteal phases averaged 19.89 days (±9.49, n = 19 phases). Gestation length (n = 2 pregnancies) was 170 days. Gestational EC and P4 concentrations were positively correlated (pregnancy A, r (132) = 0.71; pregnancy B, r (145) = 0.76) and returned to non-pregnant luteal phase levels 3-7 days post parturition. Extreme differences between pregnant and non-pregnant EC and P4 concentrations may allow for one-sample pregnancy diagnosis. Trans-abdominal ultrasonography was validated for pregnancy diagnosis with the fetus observed between 100 and 110 days post breeding. To our knowledge, this is the first use of fecal endocrinology and ultrasonography to monitor reproductive function and pregnancy in this species, and the only study in any lorisid to measure progestagens in correlation with reproductive events.

Endocrine pregnancy monitoring in the two-toed sloth (Choloepus didactylus): “Pregnant or not pregnant”

Progesterone (P4), pregnanediol glucuronide (PdG), estradiol-17β (E2), and estrone sulfate (E1S) were measured in the feces of four female two-toed sloths (Choloepus didactylus) for early pregnancy diagnosis. For individual feces assignment, the examined female sloths were fed with a turquoise food colorant every second day. Fecal samples were collected one to four times per week, depending on the defecation rate throughout the pregnancies and the postpartum periods. The complete course of pregnancy was subdivided into three 16-week intervals (trimester of pregnancy, TP1-3) and a 5-week post-partum period after birth. Progesterone and PdG concentrations started to increase above luteal phase levels 3 weeks after conception (P = 0.028 and 0.005, respectively). At the beginning of TP1, P4 concentrations averaged 345.0 ± 283.0 ng/g and increased approximately 100- to 300-fold to a peak of 7588.0 ± 6717.0 ng/g over the TP3. Progesterone concentrations were considerably lower than PdG concentrations that started with 3206.0 ± 1500.0 ng/g at TP1 and increased up to 12.8556.0 ± 53.744.0 ng/g until birth. In contrast, mean concentrations of E2 (8.2 ± 2.4–11.7 ± 4.2 ng/g) and E1S (12.2 ± 6.7–22.9 ± 13.0 ng/g) elevated insignificantly and were not suitable for pregnancy detection. All hormones analyzed decreased rapidly within the first weeks after birth. Progesterone and PdG, as well as E2 and E1S, highly significantly correlated (r = 0.602, P < 0.001 and r = 0.497, P < 0.001, respectively) at TP1. During the TP2, only P4 and PdG significantly correlated (TP2: r = 0.661, P < 0.001 and postpartum period: r = 0.616, P = 0.009). In summary, only P4 metabolite concentrations were suitable to determine the status of reproduction in the two-toed sloth. Thereby, PdG was ideally suited to diagnose early pregnancy because it was more sensitive and detected pregnancy 2 weeks earlier than P4.

The curative effect analysis of cyproterone acetate combined with letrozole in the treatment of patients with polycystic ovary syndrome and infertility

Objective To explore the clinical effect of cyproterone acetate combined with letrozole in the treatment of patients with ovulation disorder infertility caused by polycystic ovary syndrome (PCOS).Methods 124 patients with PCOS and infertility were selected and divided into three groups.Letrozole Group (42 cases) received cyproterone acetate combined with letrozole; Control Group (40 cases) received oral cyproterone acetate treatment; Clomiphene Group (42 cases) received oral cyproterone acetate combined with clomiphene.Record the sex hormone levels,cycle ovulation rate and pregnancy rate in three groups.Results The levels of T,LH,LH/FSH significantly reduced (P ＜ 0.01).In 42 ovulation induction cycles,35 cycles (87.5％) had advantaged follicle,34 cycles (85.0％) had ovulation,with 7 cases of pregnancy (17.5％).There were statistically significant differences in sex hormone levels,cycle ovulation rate,pregnancy rate between Letrozole Group and Control Group (P ＞ 0.05).E2 levels in ovulation phase and luteal phase and LH level in ovulation phase of Clomiphene Group were higher than those of Letrozole Group,without statistically significant differences (P ＞ 0.05).Conclusions Cyproterone acetate combined with letrozole in the treatment of patients with ovulation disorder infertility caused by polycystic ovary syndrome has good curative effect,can obtain same effect as clomiphene,offer one more choice for patients with ovulation disorder infertility caused by polycystic ovary syndrome. Key words: Polycystic ovary syndrome; Infertility; Letrozole; Cyproterone acetate; Clomiphene

Ovarian Regulation of Kisspeptin Neurones in the Arcuate Nucleus of the Rhesus Monkey (Macaca mulatta)

Tonic gonadotrophin secretion throughout the menstrual cycle is regulated by the negative-feedback actions of ovarian oestradiol (E₂) and progesterone. Although kisspeptin neurones in the arcuate nucleus (ARC) of the hypothalamus appear to play a major role in mediating these feedback actions of the steroids in nonprimate species, this issue has been less well studied in the monkey. In the present study, we used immunohistochemistry and in situ hybridisation to examine kisspeptin and KISS1 expression, respectively, in the mediobasal hypothalamus (MBH) of adult ovariectomised (OVX) rhesus monkeys. We also examined kisspeptin expression in the MBH of ovarian intact females, and the effect of E₂, progesterone and E₂ + progesterone replacement on KISS1 expression in OVX animals. Kisspeptin or KISS1 expressing neurones and pronounced kisspeptin fibres were readily identified throughout the ARC of ovariectomised monkeys but, on the other hand, in intact animals, kisspeptin cell bodies were small in size and number and only fine fibres were observed. Replacement of OVX monkeys with physiological levels of E₂, either alone or with luteal phase levels of progesterone, abolished KISS1 expression in the ARC. Interestingly, progesterone replacement alone for 14 days also resulted in a significant down-regulation of KISS1 expression. These findings support the view that, in primates, as in rodents and sheep, kisspeptin signalling in ARC neurones appears to play an important role in mediating the negative-feedback action of E₂ on gonadotrophin secretion, and also indicate the need to study further their regulation by progesterone.

Inactivating Mutations of the Human Luteinizing Hormone Receptor in Both Sexes

The human luteinizing hormone/chorionic gonadotropin receptor (LHCGR) plays a fundamental role in male and female reproductive physiology. Over the past 15 years, several homozygous or compound heterozygous loss-of-function mutations in the LHCGR gene have been described in males and females. In genetic males, mutations in LHCGR were associated with distinct degrees of impairment in pre- and postnatal testosterone secretion resulting in a phenotypic spectrum. Patients with the severe form of LH resistance have predominantly female external genitalia and absence of secondary sex differentiation at puberty. Patients with milder forms have predominantly male external genitalia with micropenis and/or hypospadias or only infertility without ambiguity. The undermasculization is associated with low basal, as well as human CG-stimulated, testosterone levels and elevated LH levels after pubertal age, without abnormal step-up in testosterone biosynthesis precursors. The testes have only slightly reduced size but mature Leydig cells are absent or scarce (Leydig cell hypoplasia). Genetic females with inactivating LHCGR mutations have female external genitalia, spontaneous breast and pubic hair development at puberty, and normal or late menarche followed by oligoamenorrhea and infertility. Estradiol and progesterone levels are normal for the early to midfollicular phase, but do not reach ovulatory or luteal phase levels. Serum LH levels are high whereas follicle-stimulating hormone levels are normal or only slightly increased. Pelvic ultrasound has demonstrated a small or normal uterus and normal or enlarged ovaries with cysts. The inactivating mutations of the LHCGR have provided important insights into distinct physiological roles of LH in reproduction of both sexes.