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(1/881) Changes in basement membrane thickness in the human endometrium during the luteal phase of the menstrual cycle.

We have examined aspects of the fine structure of the basal laminae associated with the luminal and glandular epithelium and small blood vessels in the human endometrium. Four short studies are presented and reviewed. Study 1 examined biopsies from 20 fertile women taken on days after the luteinizing hormone surge (LH): LH +2, 4, 6, 8 and 10. The basal lamina (both lamina densa and lucida) increased in thickness over the period studied. Study 2 again studied the glandular epithelium and examined the effect of RU486 (a progesterone receptor blocker) administered on day LH +3 and biopsied on day LH +6. The basal laminae were found to be the same as LH +2 control group but thinner than LH +6 control. Study 3 documented increased thickness of the basal laminae between LH +6, 8 and 13 in the luminal epithelium. The within-group coefficient of variation was 16% and 27% for LH +6 and LH +13 groups but only 2 % for LH +8. Study 4 demonstrated an increase in basal lamina thickness associated with small blood vessels between LH +6 and LH +10 in normal fertile women. The basal lamina provides the interface between epithelial and mesenchymal environments; changes in its structure can alter the phenotypic expression of the epithelia. It is one of the maternal barriers that must be transgressed by the trophoblast during implantation. Together, these combined studies provide quantitative baseline structural information on the electron microscopical appearance of the basal lamina during the luteal phase of the menstrual cycle.  (+info)

(2/881) Physiological variability of fluid-regulation hormones in young women.

We tested the physiological reliability of plasma renin activity (PRA) and plasma concentrations of arginine vasopressin (P[AVP]), aldosterone (P[ALD]), and atrial natriuretic peptide (P[ANP]) in the early follicular phase and midluteal phases over the course of two menstrual cycles (n = 9 women, ages 25 +/- 1 yr). The reliability (Cronbach's alpha >/=0.80) of these hormones within a given phase of the cycle was tested 1) at rest, 2) after 2.5 h of dehydrating exercise, and 3) during a rehydration period. The mean hormone concentrations were similar within both the early follicular and midluteal phase tests; and the mean concentrations of P[ALD] and PRA for the three test conditions were significantly greater during the midluteal compared with the early follicular phase. Although Cronbach's alpha for resting and recovery P[ANP] were high (0.80 and 0.87, respectively), the resting and rehydration values for P[AVP], P[ALD], and PRA were variable between trials for the follicular (alpha from 0.49 to 0.55) and the luteal phase (alpha from 0.25 to 0. 66). Physiological reliability was better after dehydration for P[AVP] and PRA but remained low for P[ALD]. Although resting and recovery P[AVP], P[ALD], and PRA were not consistent within a given menstrual phase, the differences in the concentrations of these hormones between the different menstrual phases far exceeded the variability within the phases, indicating that the low within-phase reliability does not prevent the detection of menstrual phase-related differences in these hormonal variables.  (+info)

(3/881) A quantitative study of changes in the human corpus luteum microvasculature during the menstrual cycle.

Endothelial cells are the most abundant cell type in the corpus luteum (CL), and changes in blood vessels have been proposed to play a pivotal role in CL regression. We have studied quantitatively the changes in the human granulosa-luteal microvasculature in CL of various ages: young (Days 17-19 of the cycle), mature (Days 20-24), old (Days 25-27), early regressing (follicular phase of the following cycle), and late regressing (luteal phase of the following cycle). Blood vessels were identified by immunohistochemical staining for the endothelial cell marker CD34. Because of the anisotropy of blood vessels, both vertical and transverse sections of the granulosa-lutein layer (GLL) were used to estimate relative (volume, surface, and length densities) and absolute (mean cross-sectional area) vascular variables. Full luteinization from young to mature CL was accompanied by a 61% increase in the mean cross-sectional area of vascular profiles and a 52% increase in the mean volume of granulosa-lutein cells, as an estimator of changes in the volume of the GLL. In old and early regressing CL, there was a progressive increase in relative structural vascular variables, due to the shrinkage of the GLL, whereas the mean cross-sectional area of capillaries showed a 53% decrease from mature to old CL. Finally, in late regressing CL, there was a decrease in most relative structural variables, in spite of the increasingly shrunken GLL. The decrease in the capillary diameter found at the late luteal phase most likely leads to a decreased blood flow, and early changes in blood vessels could initiate and/or accelerate CL regression.  (+info)

(4/881) Endometrial evaluation is not predictive for in vitro fertilization treatment.

PURPOSE: The main purpose of this study was to evaluate ovarian function by clomiphene citrate (CC) challenge test in a group of tubal infertile women and to study endometrial morphological maturation in the early luteal phase of CC-stimulated cycles as compared to in vitro fertilization (IVF) treatment outcome. METHODS AND RESULTS: Four women presented with strongly retarded, proliferative endometrium in the luteal phase. Of these, three presented with impaired ovarian function, high basal follicle-stimulating hormone, and high follicle-stimulating hormone levels after clomiphene stimulation on cycle day 10. In the remaining 30 women, showing an in-phase endometrium after CC stimulation, a comparison of six morphological characteristics did not reveal any significant differences between the 14 women who did become pregnant and the 16 who did not. No significant differences in endometrial thickness were observed between the groups. Significant differences were found when comparing estradiol and progesterone area under the curve during the luteal phase (P < 0.001 and P < 0.01, respectively) between those who did and those who did not become pregnant. CONCLUSIONS: Luteal endometrium morphology was not a sharp instrument to detect differences between women who did and women who did not become pregnant following IVF treatment, while ovarian function, as measured by hormonal markers, seemed to be a more reliable prognostic factor for IVF treatment outcome.  (+info)

(5/881) Fluctuations in CA 125 and CA 15-3 serum concentrations during spontaneous ovulatory cycles.

The aim of this study was to investigate cycle dependent changes of serum CA 125 and CA 15-3 concentrations during spontaneous ovulatory cycles. Twenty apparently healthy women with spontaneous menstrual cycles attending our infertility clinic were included. Of these women, 18 had occluded tubes as a result of sterilization. Ovulation was confirmed by luteinizing hormone test and ultrasonography and, to exclude endometriosis, a laparoscopy was performed. Serum samples for CA 125, CA 15-3, 17 beta-oestradiol and progesterone determinations were taken every second day starting on the 2nd day of the cycle until the 7th day of the next cycle. After correction for inter-individual variation in serum concentrations, highest CA 125 concentrations were found during the menstruation. During the follicular and peri-ovulatory phase CA 125 serum concentrations were lowest. For CA 15-3, serum concentrations were not statistically different throughout the cycle. CA 125 and oestradiol concentrations were negatively correlated, CA 15-3 and oestradiol concentrations were positively correlated. Absolute serum concentrations of both CA 125 and CA 15-3 vary among females. Within the female, fluctuations of CA 125 are phase related. In the population studied most of the patients had tubal obstruction and high CA 125 serum concentrations during menstruation, which revokes the theory that the menstrual rise of CA 125 is due only to retrograde menstruation.  (+info)

(6/881) Steroidogenic enzyme expression in human corpora lutea in the presence and absence of exogenous human chorionic gonadotrophin (HCG).

In a human conception cycle, the expected decline in progesterone production by the corpus luteum during the late luteal phase is prevented by human chorionic gonadotrophin (HCG) secreted by the implanting blastocyst. This study investigated the expression of components of the synthetic pathway for progesterone in human corpora lutea in the presence and absence of HCG in vivo. Corpora lutea were obtained from: (i) normally cycling women at the time of hysterectomy and classified on the basis of the urinary luteinizing hormone (LH) surge as early (n = 3), mid- (n = 3), or late luteal (n = 3); or (ii) women who had received daily doubling doses of HCG (n = 3) to 'rescue' the corpus luteum. Expression patterns of steroidogenic acute regulatory protein (StAR), cytochrome P450 cholesterol side-chain cleavage (P450scc) and 3beta-hydroxysteroid dehydrogenase (3beta-HSD) were investigated by Northern blotting, in-situ hybridization and immunohistochemistry. Luteal 'rescue' with HCG was associated with the continued expression of these components. In the late luteal phase, in the absence of HCG, expression remained but was more variable. The expression of 3beta-HSD mRNA was significantly reduced during the luteal phase (P<0.01). In conclusion, during luteal 'rescue', HCG acts to maintain the steroidogenic pathway. In the absence of HCG, the decline in progesterone production begins in the presence of the main components of the steroidogenic pathway. While unlikely to initiate this decline, the altered expression levels of these components, particularly that of 3beta-HSD, may contribute to the continued reduction in progesterone production.  (+info)

(7/881) Human albumin enhances expression of vascular endothelial growth factor in cultured human luteinizing granulosa cells: importance in ovarian hyperstimulation syndrome.

Ovarian hyperstimulation syndrome (OHSS) is a severe complication of ovarian stimulation for assisted reproductive techniques. Clinical manifestations are massive extravascular fluid accumulation and haemoconcentration. Vascular endothelial growth factor (VEGF) has been demonstrated to mediate the development of OHSS. Intravenous albumin at the time of oocyte aspiration has been suggested as an effective prophylactic treatment against the occurrence of severe OHSS. Here it is reported that in cultured human luteinizing granulosa cells, VEGF mRNA expression was enhanced by human albumin and maximum expression was observed in cultured granulosa cells obtained from patients with serum oestradiol concentrations >2000 pg/ml on the day of human chorionic gonadotrophin injection (P < 0. 05).  (+info)

(8/881) Main inhibitor of follicle stimulating hormone in the luteal-follicular transition: inhibin A, oestradiol, or inhibin B?

The roles of oestradiol, inhibin A and inhibin B in the luteal-follicular transition were assessed by means of specific assays. Six premenopausal women were studied during a control and then a cycle treated with percutaneous oestradiol 0.1 mg/day from day 10 after the luteinizing hormone (LH) surge until day 4 of the following cycle. Inhibin A concentrations decreased similarly in control and treated cycles from day -5 to day 2, then increased in control cycle to 23.3 +/- 3.4 pg/ml on day 10 (mean +/- SEM). They remained low until day 5 in treated cycles and were lower than controls on day 10 (P < 0.01). Follicle stimulating hormone (FSH) concentrations increased on day 1 in controls and on day 5 in treated cycles when oestradiol concentration fell abruptly. Inhibin B concentrations remained low until day 1 in controls and day 4 in treated cycles. In both, inhibin B concentrations increased 1 day after FSH, peaking at 160 pg/ml. FSH concentrations began to plateau when inhibin B concentrations were >100 pg/ml and oestradiol concentrations below 200 pmol/l. These data suggest that inhibin A is not responsible for FSH suppression in the luteal phase and that the negative control of FSH shifts from oestradiol in the luteal phase to inhibin B in the mid-follicular phase.  (+info)