Myometrial Area Research Articles

Dynamics of T2* and deformation in the placenta and myometrium during pre-labour contractions

Pre-labour uterine contractions, occurring throughout pregnancy, are an important phenomenon involving the placenta in addition to the myometrium. They alter the uterine environment and thus potentially the blood supply to the fetus and may thus provide crucial insights into the processes of labour. Assessment in-vivo is however restricted due to their unpredictability and the inaccessible nature of the utero-placental compartment. While clinical cardiotocography (CTG) only allows global, pressure-based assessment, functional magnetic resonance imaging (MRI) provides an opportunity to study contractile activity and its effects on the placenta and the fetus in-vivo. This study aims to provide both descriptive and quantitative structural and functional MR assessments of pre-labour contractions in the human uterus. A total of 226 MRI scans (18–41 weeks gestation) from ongoing research studies were analysed, focusing on free-breathing dynamic quantitative whole uterus dynamic T2* maps. These provide an indirect measure of tissue properties such as oxygenation. 22 contractile events were noted visually and both descriptive and quantitative analysis of the myometrial and placental changes including volumetric and T2* variations were undertaken. Processing and analysis was successfully performed, qualitative analysis shows distinct and highly dynamic contraction related characteristics including; alterations in the thickness of the low T2* in the placental bed and other myometrial areas, high intensity vessel-like structures in the myometrium, low-intensity vessel structures within the placental parenchyma and close to the chorionic plate. Quantitative evaluation shows a significant negative correlation between T2* in both contractile and not-contractile regions with gestational age (p < 0.05) as well as a significant reduction in T2* during contractions. The T2* values in the myometrium were however not correlated to gestational age (p > 0.5). The quantitative and qualitative description of uterine pre-labour contractions including dynamic changes and key characteristics aims to contribute to the sparsely available in-vivo information and to provide an in-vivo tool to study this important phenomenon. Further work is required to analyse the origins of these subclinical contractions, their effects in high-risk pregnancies and their ability to determine the likelihood of a successful labour. Assessing T2* distribution as a marker for placental oxygenation could thus potentially complement clinically used cardiotocography measurements in the future.

Ovarian, uterine, and luteal vascular perfusions during follicular and luteal phases in the adult cyclic female rabbits with special orientation to their histological detection of hormone receptor

Understanding the does reproductive hemodynamic changes during the estrous cycle is crucial for improving reproductive competence and fertility potential in this species. The objective of this study is to investigate the hemodynamic variations in ovarian (OA) and uterine (UA) arteries, histological and morphometric changes in ovarian and uterine tissues throughout the follicular (FP) and luteal (LP) phases in rabbits and determine estrogen (ER), progesterone (PR) receptors, and vascular endothelial growth factor (VEGF) distributions using immunohistochemistry.Fourteen adults pluriparous New Zealand rabbits were divided into rabbits at the FP (Day − 1; n = 7) and those at the LP (Day 9; n = 7). Animals were subjected to Doppler, hormonal (estrogen [E2], progesterone [P4], insulin-like growth factor [ILGF], and VEGF), histological, and immunohistochemical analyses. In LP, OA Doppler indices were significantly increased, whereas peak systolic velocity (PSV) was decreased compared with that in FP. UA Doppler indices were significantly decreased in the LP, whereas PSV was increased (P < 0.05). E2 levels were increased in the FP, whereas P4 levels were increased in the LP. The morphometric analysis of uterine tissues during the LP revealed an increase in the mean uterine endometrium length, endometrial connective tissue area percentage (%), endometrial glands number, myometrial area (%) and thickness. Furthermore, ovarian follicles and corpus luteum (CL) displayed strong positive immunoreactivity for ER, PR, and VEGF-A during both phases. The ovarian sections displayed a substantial (P < 0.05) increase in the area % of VEGF-A in the ovarian follicles during FP while in the CL during LP. Conversely, area percentage of VEGF-A immunoreactivity in the uterine luminal and glandular epithelia during the FP and LP revealed no differences. However, the number of VEGF-A–stained blood capillaries revealed an increase during LP than FP. In conclusion, this study demonstrated for the first time the changes in both ovarian and uterine arteries during two different phases of the rabbit cycle in relation to the histo-morphometric analysis and distribution of ER, PR, and VEGF-A, which regulate uterine functions that play a role in reproduction.

Endometrial and Myometrial Multidimensional Growth During the Cycle

Three-dimensional sonography enables assessment of uterine morphology. While the pattern of endometrial growth has been well described, little information is available on changes in endometrial and myometrial volume, area, and perimeters. We evaluated the ratio between myometrial and endometrial dimensions and its relation to endometrial thickness of inpatients with normal uterine morphology from our hospital. Routine hormonal assessment on the day of the sonographic exam was extracted from electronic medical records. Correlations between different dimensions of the uterus were examined. A total of 38 3D sonographic data sets were reviewed. A significant correlation was found between estradiol blood levels and endometrial thickness, area, and volume (R = 0.35, 0.53, 0.55, respectively; P &lt; .05). The ratio between the endometrial and myometrial area remained constant regardless of endometrial thickness. The findings of this study suggest that endometrial thickness, area, and volume may correlate with circulating estradiol levels. Endometrial and myometrial changes correlated in more than one dimension.

Development and Characterization of Uterine Glandular Epithelium Specific Androgen Receptor Knockout Mouse Model1

While estrogen action is the major driver of uterine development, androgens acting via the androgen receptor (AR) may also promote uterine growth as suggested by uterine phenotypes in global AR knockout (ARKO) female mice. Because AR is expressed in uterine endometrial glands, we generated (Cre/loxP) uterine gland epithelium-specific ARKO (ugeARKO) to determine the role of endometrial gland-specific androgen actions. However, AR in uterine gland epithelium may not be required for normal uterine development and function because ugeARKO females had normal uterine development and fertility. To determine if exogenous androgens acting via AR can fully support uterine growth in the absence of estrogens, the ARKO and ugeARKO females were ovariectomized and treated with supraphysiological doses of testosterone or dihydrotestosterone (nonaromatizable androgen). Both dihydrotestosterone and testosterone supported full uterine regrowth in wild-type females while ARKO females had no regrowth (comparable to ovariectomized only). These findings suggest that androgens acting via AR can promote full uterine regrowth in the absence of estrogens. The ugeARKO had 50% regrowth when compared to intact uterine glands, and histomorphologically, both the endometrial and myometrial areas were significantly (P < 0.05) reduced, suggesting glandular epithelial AR located in the endometrium may indirectly modify myometrial development. Additionally, to confirm Cre function in endometrial glands, we generated uge-specific PTEN knockout mouse model. The ugePTEN knockout females developed severe endometrial hyperplasia and therefore present a novel model for future research.

Histological Structure and Vascularity of Hysteroscopically Removed Uterine Septa in Patients With Primary Infertility and Patients With Recurrent Pregnancy Loss

ObjectiveTo examine the histological structure and vascularity of uterine septa in patients with unexplained primary infertility and patients with recurrent pregnancy loss (RPL). DesignCase-control study (Canadian Task Force classification II-2). SettingKasr Al Aini Hospital, Cairo University, Egypt. Patients and InterventionsA total of 41 patients with uterine septa presenting with either unexplained primary infertility or RPL underwent 3-dimensional (3D) and power Doppler (PD) ultrasound to calculate the septum volume, septal vascularization index (VI), and myometrial VI. Hysteroscopically removed septa were examined histologically for myometrial and fibrous tissue content. Measurements and Main ResultsSeptal characteristics differed between the primary infertility group (24 patients) and the RPL group (17 patients). Mean septal VI was significantly higher in the RPL group compared with the infertility group (18.39% ± 7.57% vs 11.67% ± 4.56%; p = .003), as was meptal myometrial area (20.74% ± 5.97% vs 13.57% ± 5.55%; p < .001). In both groups, septal VI was strongly correlated with myometrial VI and myometrial content, but not with fibrous tissue content. ConclusionUterine septa of patients with RPL are more vascularized and contain more muscular tissue compared with those of patients with primary unexplained infertility.

Increased incidence of placenta praevia and accreta with previous caesareans – A hypothesis for causation

With the increasing numbers of caesareans, long-term complications, such as anterior placenta praevia-accreta are becoming important. Two case reports are presented here, leading to a hypothesis that the increasing incidence of anterior placenta praevia after prior caesareans may be a result of excessive differential development of the lower uterine segment. This could result from marked stretching of a poorly-healed myometrial area by the developing placenta. This would explain the lower incidence of ‘apparent’ migration of low placenta, as well as the higher likelihood of morbid adhesion. Although different operative techniques do not have a significant effect on short-term outcomes of caesareans, they are likely to impact the long-term complications. In the absence of long-term studies and good quality evidence, theoretical and logical analysis suggests that adherence to good surgical techniques, such as gentle tissue handling, haemostasis, good myometrial approximation without compromising blood supply and restoration of normal anatomy, may reduce long-term complications.

Ultrasound evaluation of uterine healing after laparoscopic intracapsular myomectomy: an observational study

Can uterine scar healing after laparoscopic intracapsular myomectomy (LIM) be adequately monitored by traditional two-dimensional (2D) ultrasound (US) and Doppler velocimetry? The myometrial area of the scar after LIM can be followed by 2D US and Doppler velocimetry. Apart from post-surgical adhesions, the main concern linked to laparoscopic myomectomy is the quality of healing of the myometrial incision: it has been suggested that US could be useful for assessing uterine scars after myomectomy. However, no diagnostic method has yet been widely accepted to assess the healing process. A cohort prospective study (level of evidence II-2), run in University-affiliated hospitals: 149 women with symptomatic uterine fibroids (UFs) underwent LIM, between January 2007 and October 2011. During follow up 13 patients withdrew from the study. After LIM, all patients were followed by traditional 2D US scanning and Doppler velocimetry on Days: 0, 1, 7, 30 and 45. Authors evaluated: number, size and location of UFs, scar diameter and Doppler velocimetry and resistance index (RI) of the uterine arteries, at their ascending branch. The uterine examination showed a significant (P < 0.05) progressive reduction of uterine scar area from 78% of the previous UF location on the first day, to 19% on 30th day, and <4% on the 45th day. There was no correlation with the size of the fibroid or the relative reduction in the size of the scar, on both Days 1 and 45. There was a significant (P < 0.05) increase in the RI of the ipsilateral uterine arteries from 0.65 on the first post-operative day to 0.83 after 7 days followed by a decrease to 0.71 on the 30th and 0.61 on the 45th post-operative day. This is a cohort investigation on a limited number of patients and it does not surgically compare LIM and 'classic' myomectomy in the scar US follow up. LIM avoided intraoperative bleeding and excessive tissue damage, as post-operative US follow up showed, with just two intra-myometrial hematomas (1.5%). The 2D US and Doppler velocimetry, a non-invasive safe method to check the myometrium after LIM, can detect post-operative hematoma and disechogenic, heterogeneous or ill-defined scar area, all unfavorable signs for myometrial scarring. Moreover, Doppler transvaginal monitoring, evaluating the pulsatility index (PI) and RI of the uterine arteries at their ascending branch, could identify patients with altered PI and RI parameters, possible markers of impaired wound healing.

Subfertile Female Androgen Receptor Knockout Mice Exhibit Defects in Neuroendocrine Signaling, Intraovarian Function, and Uterine Development But Not Uterine Function

Female androgen receptor (AR) knockout mice (AR(-/-)) generated by an in-frame Ar exon 3 deletion are subfertile, but the mechanism is not clearly defined. To distinguish between extra- and intraovarian defects, reciprocal ovarian transplants were undertaken. Ovariectomized AR(-/-) hosts with wild-type (AR(+/+)) ovary transplants displayed abnormal estrus cycles, with longer cycles (50%, P < 0.05), and 66% were infertile (P < 0.05), whereas AR(+/+) hosts with either AR(-/-) or surgical control AR(+/+) ovary transplants displayed normal estrus cycles and fertility. These data imply a neuroendocrine defect, which is further supported by increased FSH (P <0.05) and estradiol (P <0.05), and greater LH suppressibility by estradiol in AR(-/-) females at estrus (P <0.05). Additional intraovarian defects were observed by the finding that both experimental transplant groups exhibited significantly reduced pups per litter (P < 0.05) and corpora lutea numbers (P < 0.05) compared with surgical controls. All groups exhibited normal uterine and lactation functions. AR(-/-) uteri were morphologically different from AR(+/+) with an increase in horn length (P < 0.01) but a reduction in uterine diameter (P < 0.05), total uterine area (P < 0.05), endometrial area (P < 0.05), and myometrial area (P < 0.01) at diestrus, indicating a role for AR in uterine growth and development. Both experimental transplant groups displayed a significant reduction in uterine diameter (P < 0.01) compared with transplanted wild-type controls, indicating a role for both AR-mediated intraovarian and intrauterine influences on uterine physiology. In conclusion, these data provide direct evidence that extraovarian neuroendocrine, but not uterine effects, as well as local intraovarian AR-mediated actions are important in maintaining female fertility, and a disruption of AR signaling leads to altered uterine development.

Use of three-dimensional ultrasonography in the evaluation of uterine perfusion and healing after laparoscopic myomectomy

To evaluate vascular perfusion and uterine healing after laparoscopic myomectomy using three-dimensional power Doppler ultrasound (3D-PDU). Prospective study. University-affiliated hospital. Ninety-seven women with symptomatic myomas warranting laparoscopic myomectomy. Three-dimensional PDU obtained preoperatively and 1 week and 3 months postoperatively. Resistance index, pulsatility index, and peak systolic velocity of the uterine artery; vascularization index, flow index, and vascularization flow index of the uterine tissue, nonoperative area, and healing myometrial area. The median age was 39 years. More than half of the patients were nulliparous, and one third desired fertility. The median myoma size was 8 cm, and median weight of the extirpated myomas was 250 g. The median myoma volume was 262 cm(3), and median uterine volume was 380 cm(3). On the 7th postoperative day all laparoscopic myomectomy healing sites appeared as highly echogenic areas with profuse blood flow at the periphery and reduced resistance index and pulsatility index of the uterine artery. Nonoperated areas had significantly more blood flow than healing areas. Two patients had hematomas, which appeared as hypoechoic areas that were almost avascular. By the 3rd postoperative month the blood flow and uterine volume decreased significantly. However, an 11-cm(3) hypoechoic hematoma with poor tissue perfusion was still seen in 1 patient with a 720-cm(3) myoma. Healing of a laparoscopic myomectomy scar can be evaluated by 3D-PDU. Adequate perfusion demonstrated by 3D-PDU might suggest good wound healing and dissolving of hematomas.

237. AR-mediated androgen actions are essential for normal mouse uterine growth and development but not implantation and embryo development

Recently the androgen receptor (AR) has been shown definitively to play a role in female reproduction. We generated a homozygous AR−/− female mouse using Cre/LoxP recombination for an in-frame excision of exon 3, encoding the second zinc finger essential for DNA-binding, while allowing production of an exon 3 deleted mutant AR protein which is nonfunctional as a nuclear transcription factor. AR−/− females were sub-fertile due primarily to ovulatory dysfunction (1). However, the mechanism(s) of the observed sub-fertility remains to be fully defined. To evaluate the role of AR in uterine function we carried out a morphological and function analysis of the AR−/− uterus. Uterine weights did not differ, however, AR−/− females exhibited a significant increase in uterine horn length (P &lt; 0.01), and a significant reduction in uterine diameter (P &lt; 0.01), total uterine area (P &lt; 0.01), endometrial area (P &lt; 0.05) and myometrial area (P &lt; 0.01), indicating a role for genomic AR-mediated actions in physiological uterine growth and development. Furthermore, during late pregnancy AR−/− females had significantly fewer implantation sites (P &lt; 0.01), fetuses present in utero (P &lt; 0.05) and a lower serum progesterone concentration (P &lt; 0.01). In spite of these findings, AR−/− females had normal gestational length, parturition and pup weights, as well as similar pre- and post implantation losses compared with AR+/+ females. Therefore, although AR is not essential for normal uterine reproductive function, disrupting genomic AR signalling in the uterus leads to dysfunctional uterine development which may have important long-term functional consequences for hormone dependent uterine disorders such as endometrial hyperplasia and cancer. (1) K. A. Walters et al. Endocrinology 148, 3674 (2007).

Comparison of 2-, 3D and doppler ultrasound with histological findings in adenomyosis

Reliable diagnosis and determination of extent of adenomyosis is critical to determining therapy. The most common preoperative diagnostic tool is ultrasound (U/S). Different sonographic features of adenomyosis have been reported in the literature. The diagnostic accuracy of 2D-, 3D and Doppler U/S were compared to histological findings in hysterectomy specimens in cases of Adenomyosis. A comparative study of 2-, 3D and Doppler ultrasound with histological findings in adenomyosis. Under an IRB-approved protocol, 60 women (35–45years of age) with menorrhagia and/or pain and the presumptive diagnosis of adenomyosis were studied by transvaginal U/S examination using 2D-, 3D- and Doppler transvaginal U/S (Sono Ace model 9900 ultrasound instrument, Medaison, Korea). The diagnostic criteria tested were a bulky or globular-appearing uterus, asymmetric wall thickness, mottled non homogenous myometrium with ill defined borders, small non vascular cystic areas, ill-defined endometrial lines, vascular myometrium with random scattered or perpendicular vessels to long axis of the uterus, hazy or ill-defined and irregular endometrial-myometrial junction in the coronal view of the 3D uterine cavity scan. After hysterectomy, specimens were processed and examined by the same pathologist who was blinded to ultrasound findings. 83.3% of the cases had histological confirmation of adenomyosis. Among the positive cases the highest sensitivity rate was for the non-homogenous or heterogeneous myometrial area with ill-defined boundaries (90%). The highest specificity was for intra-myometrial cysts (90%). The highest positive predictive value (PPV) was for intra-myometrial cysts (97.2%), followed by heterogeneous or non-homogenous ill defined myometrial area, asymmetric wall thickness, and ill-defined endometrial myometrial junction seen in the coronal view of 3D uterine cavity scan with a similar positive predictive value (95.7%, 95.4, and 95.2%). The highest accuracy was for non-homogenous myometrium (88.3%) followed by asymmetric wall thickness, ill-defined endometrial –myometrial junction in coronal view of 3D uterine cavity scan and globular uterus with accuracy of 83.3%, 80%, and 80% respectively. Abnormal Doppler findings had the lowest accuracy (51.6%). Adenomyosis produces a spectrum of pathological changes in the uterus and variable U/S features. The use of formalized scoring criteria could improve diagnostic accuracy and planning of treatment.

The effect of oral contraceptives on uterine contractility and menstrual pain: an assessment with cine MR imaging

Low-dose oral contraceptives (OC) have been reported to control primary dysmenorrhea. Furthermore, a close relationship between dysmenorrhea and uterine contractions has been visualized with magnetic resonance imaging (MRI). This study aimed to use cine MR to demonstrate the effects of OC on myometrial contractility during menstruation and to associate the findings with dysmenorrhea. MR studies were obtained of 21 healthy female volunteers (22-47 years old) taking OC, and 20 control women (24-39 years old) not taking OC. Cine- and static MR images were obtained with a 1.5 T magnet during menstruation. Uterine contractility was assessed by the presence of endometrial distortion on cine MR, the area of the mid-sagittal uterine myometrium, and the thickness of the subendometrial low-intensity area on static images. Dysmenorrhea were assessed via a questionnaire. A total of 21 OC users and 20 controls were included in the analysis. Endometrial distortion was significantly less prominent and the subendometrial low-intensity area was significantly thinner in the OC group. Furthermore in the OC group, the uterine myometrial area was larger (although not significantly) and the degree of assessed pain was significantly lower. Both cine- and static MR images demonstrate that myometrial contractility was relatively suppressed in OC users, which may represent one of the reasons explaining the reduced menstrual pain experienced by OC users.

21

The second generation thermal ablation devices have been widely accepted as alternative therapies for the treatment of menorrhagia. What may be less understood by the treating gynecologist are the mechanism of thermal penetration for these devices and more importantly the depth of thermal penetration of each device into the uterine tissue. Evidence of serosal heating in the absence of uterine perforation exists for second generation devices, as evident by a review of reports to the FDA MAUDE data base and journal publications. In this evaluation, transvaginal ultrasound was employed to measure the myometrium as a pre-operative assessment for patients prior to endometrial ablation. A minimum myometrium measurement was used to determine patient candidacy for thermal endometrial ablation. Urban gynecology group practice. Pre-menopausal women presenting for evaluation and consultation for treatment options for excessive menstrual bleeding. Transvaginal ultrasound prior to endometrial ablation. Depths of thermal penetration based on documentation within SSEDs and publications for the devices will be presented to support the understanding and importance on the use of ultrasound to successfully identify patients with thinned myometrial areas, and thus exclude them from treatment with a thermal endometrial ablation device. Ultrasound examples will be presented to demonstrate myometrial evaluation, complex scenarios for assessment, and regions of identified thin areas. Transvaginal ultrasound is a valuable tool for assessment of the myometrium prior to thermal endometrial ablation. Particular attention should be paid to patients with LTCS scars or other uterine surgery in order to reduce the risk of injury in the presence of a thinned myometrium.

LYVE-1 immunohistochemical assessment of lymphangiogenesis in endometrial and lung cancer

Aims/Methods: Normal and malignant pulmonary and endometrial tissues were analysed for lymphatic vessels to assess the process of lymphangiogenesis and its role at these sites, using specific immunostaining for LYVE-1...

Effects of endocrine disrupting compounds on the pathology and oestrogen receptor α and β distribution in the uterus and cervix of ewe lambs

A number of chemicals have been classed as endocrine disrupting compounds due to their ability to mimic the actions of endogenous hormones in vivo and in vitro. The objective of this experiment was to determine the pathological changes and oestrogen receptor (ER) distribution in the cervix and uterus of prepubertal ovariectomised ewe lambs following exposure to a range of compounds with a predominantly oestrogenic effect. Lambs were exposed to diethylstilbestrol (0.175 mg/kg biweekly), bisphenol-A (3.5 mg/kg biweekly) or octylphenol (3.5 mg/kg biweekly) for 6 weeks. Following sacrifice, uterine and cervical tissue pathology was assessed. The endometrial and myometrial areas were quantified and the distribution of ERα and ERβ assessed by immunohistochemistry. No differences were observed between control and octylphenol-exposed lambs in uterine gross pathology and histopathology. Uteri from bisphenol-A- and diethylstilbestrol-exposed lambs were heavier than both control and octylphenol-exposed lambs. In the bisphenol-A-exposed lambs, endometrial oedema accounted for a significant increase in the endometrial cross-sectional area over the other groups. Uteri from animals exposed to diethylstilbestrol showed variable pathology including oedema and cellular proliferation. Keratinisation of the cervical epithelium was observed in both bisphenol-A- and diethylstilbestrol-exposed lambs. Exposure to diethylstilbestrol and bisphenol-A was associated with a diffuse intracellular distribution of ERα and ERβ in the uterine endometrium. This was in addition to the strong cytoplasmic staining of uterine epithelial cells and nuclear staining of specific sub-epithelial cells observed in all groups. We conclude that a 6-week exposure of lambs to bisphenol-A and diethylstilbestrol altered the uterocervical environment and has the potential to disrupt subsequent reproductive function. Pathological changes could not be detected in the uterus or cervix of lambs exposed to octylphenol.

Axonal degeneration and regeneration in rat uterus during the estrous cycle

Uterine innervation of the adult virgin rat changes throughout the estrous cycle. Nerves immunoreactive for the pan-neuronal marker protein gene product 9.5 and the sympathetic marker dopamine β-hydroxylase are maximal at diestrus and minimal at estrus, whereas presumptive sensory and parasympathetic axons are unchanged. In the present study, we used quantitative electron microscopy to determine if depletion of immunoreactive nerves from the myometrium is due to loss of structurally intact axons, and whether this occurs through degeneration or retraction. Numbers of intact myometrial axons per unit sectional area were greatest at diestrus and least at estrus, while myometrial area was smallest at diestrus and greatest at estrus. However, depletion of intact axons at estrus was evident even after correcting for changes in uterine size. Varicosities adjacent to smooth muscle cells did not vary significantly with respect to their ultrastructural features or distance to the nearest smooth muscle target cell. Because retracting axons show increases in organelle content and distances to target cells, retraction probably does not play a major role in reducing uterine innervation. In contrast, axons with ultrastructural features consistent with degeneration (organelle and axolemmal disintegration, abnormal electron opacity, dense inclusion bodies) were significantly increased at proestrus and estrus. Growth cones were observed only at metestrus and diestrus. We conclude that cyclical degeneration and regeneration of myometrial innervation is a normal feature of the virgin adult rat.

Intravascular Ultrasound Contrast Agent: An Aid in Imaging Intervillous Blood Flow?

The aim of this study was to evaluate the applicability of an intravascular ultrasound contrast agent in examination of the uteroplacental circulation.Uteroplacental circulation in 25 singleton third trimester pregnancies was examined by power Doppler, first without and then with contrast agent enhancement (Levovist\\R, Schering AG, Germany). Eight subjects had fetal growth retardation and 17 had normal-sized fetuses. The effect of the contrast agent was evaluated using computerized power Doppler signal intensity measurements.The Doppler signal intensity in the uteroplacental vessels increased within 25 sec of brachial venous injection of the contrast agent, yielding an effect which was recognizable up to 5–8min later. There was clear enhancement of uteroplacental flow imaging after addition of the contrast agent in all of the examined pregnancies. The mean percentual intensity changes after administration of the contrast agent were 33 per cent (P<0.001) in the sub-placental myometrial area and 8 per cent (P<0.001) in the intraplacental area. No association was found between fetal growth retardation and intensity changes or absolute intensity parameters.In conclusion, intravascular ultrasound contrast agent facilitates imaging of the uteroplacental circulation. It may have a valuable role in determination of intervillous blood flow and in imaging blood perfusion in different regions of the placenta.

Effect of prepubertal retinyl palmitate treatment on uterine development and subsequent uterine capacity in swine.

The effect of prepubertal retinyl palmitate treatment on uterine development and uterine capacity was determined. Gilts remained intact or were unilaterally hysterectomized-ovariectomized (UHO) on d 28, 84, or 112 of age. Starting at birth, half of the gilts in each UHO group were treated with retinyl palmitate (14,000 IU.kg-1.wk-1) and half received control carrier solution. All intact gilts received control carrier solution. Blood samples (d 28, 56, 84, and 112 of age) were analyzed for retinoid and retinol-binding protein (RPB). At UHO, part of the excised uterine horn was processed for morphometric analysis of the uterine wall, and tissues were incubated in minimal essential medium with [3H]leucine to assess total protein and RBP production. After puberty, gilts were mated and then killed on d 44 to 47 of pregnancy; uterine length, number of corpora lutea and fetuses, and fetal, placental, and empty uterine weights were recorded. Endometrial tissues were incubated in minimal essential medium with [3H]leucine, and nondialyzable radioactivity, acid phosphatase, and RBP production were measured. During the prepubertal period, retinyl palmitate treatment decreased (P < .05) myometrial area (longitudinal and circular), but it had no effect on other components of the uterine wall or production of nondialyzable radioactivity or secretion of RBP by uterine tissue. During pregnancy, prepubertal retinyl palmitate treatment increased (P < .05) uterine length but had no effect on uterine weight, number of fetuses, placental or fetal weights, or endometrial production of nondialyzable radioactivity, acid phosphatase, or RBP. Therefore, prepubertal retinyl palmitate treatment at the dosage administered had no effect on uterine capacity.

Neonatal exposure to progesterone and estradiol alters uterine morphology and luminal protein content in adult beef heifers

Exposure of the developing urogenital tract to steroids can affect structure and function of adult tissues and compromise reproductive performance. This study was conducted to determine 1) if exposure of neonatal heifer calves to progesterone (P) and estradiol benzoate (E), delivered from a commercial growth-promoting implant, would affect adult uterine morphology or uterine luminal protein content; and 2) whether such effects would be related to neonatal age at the first exposure. At birth (Day 0), 20 crossbred beef heifers were assigned to 1 of 4 treatment groups (n = 5 per group), defined by age at implant placement. Heifers either received an implant on Days 0, 21 or 45, or served as untreated controls. The heifers were maintained together and slaughtered at 15 mo of age, during the luteal phase of an induced estrous cycle, when reproductive tracts and blood samples were obtained. Peripheral plasma P concentrations were determined by RIA. Uterocervical wet weights were recorded, and uterine luminal flushings (ULF) were assayed for total protein. Cross-sections of uterine tissues were evaluated histomorphometrically to determine myometrial and endometrial areas and relative endometrial gland density. Treatment did not affect plasma P concentrations (3.2 ± 0.5 ng/ml). Regardless of age at treatment, neonatal PE exposure reduced uterocervical wet weight by 35% (112.8 < 173.9 ± 13.9 g; P < 0.01), myometrial area by 23% (125.3 < 162.8 ± 8.5 mm 2; P < 0.02), and endometrial area by 27% (33.3 < 45.4 ± 2.7 mm 2; P < 0.09) compared with the untreated controls. Endometrial gland density was reduced (P < 0.01) by 40% in treated heifers. This effect was related to age at implant placement. Uterine gland density was reduced (P < 0.01) by 65% in heifers treated at birth, while reductions of 22 and 33% were observed for heifers treated on neonatal Day 21 or 45, respectively. Consistently, ULF protein content was lower (P < 0.01) in the treated heifers (2.67 < 4.98 ±. 72 mg/ULF). Thus, exposure of newborn calves to PE can have profound effects on adult uterine morphology and environment, the extent of which may depend upon the developmental period when exposure occurs. The potential of such alterations to affect reproductive performance in adult beef heifers remains to be investigated.

Effects of sex steroid implants on reproductive tissues of female garter snakes (Thamnophis sirtalis).

Female Thamnophis sirtalis were administered intraperitoneal implants of either estradiol 17β (E2), testosterone (T), 5α-dihydrotestosterone (DHT), or empty silastic capsules for 3 weeks. Plasma levels of E2 and T, measured by specific radioimmunoassay, were significantly elevated in E2 and T-implanted females when compared to controls. T-implanted females did not have elevated circulating E2 levels, suggesting that E2 in the plasma normally is not derived from peripheral conversion of T to E2. Implantation of DHT did not significantly change circulating levels of E2, T, or DHT. All three sex steroid-treated groups of animals had increased oviductal mass compared to controls, while hepatic mass of only E2-treated animals was significantly greater. None of the steroid treatments influenced ovarian mass. Oviductal epithelial cell height and area were greater in the three steroid-treated groups. Testosterone increased myometrial area while DHT drastically altered oviductal morphology. Hepatic cell area and number increased significantly in E2-treated females. However, a small increase in both hepatic cell area and number was noted in T- and DHT-treated females as well. These results suggest that androgen in both an aromatizable and non-aromatizable form can affect the oviduct of females but that the liver primarily responds to estrogenic steroids. © 1992 Wiley-Liss, Inc.