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At least 37 records · Page 2Linked to original sources
PubMed2006

Sonographic findings of placental lacunae and the prediction of adherent placenta in women with placenta previa totalis and prior Cesarean section.

OBJECTIVE: To investigate the value of transvaginal sonographic findings of intraplacental lacunae for predicting adherent placenta and clinical outcome in patients with placenta previa totalis and a history of Cesarean section. METHODS: Fifty-one patients with placenta previa totalis diagnosed by transvaginal sonography and with a history of Cesarean section who delivered at our hospital were included in the study. The sonographic findings of intraplacental lacunae were classified into one of four grades. Pathological analysis of the placenta was performed for all patients who delivered, and in cases of hysterectomy, examination of the uterus was also performed. The placental findings and obstetric complications, including massive transfusion, intensive care unit admission and Cesarean hysterectomy, were compared with the grade of lacuna. RESULTS: Lacunae were classified as Grade 1+ in 10 cases, Grade 2+ in 11 cases, Grade 3+ in five cases and as Grade 0 (i.e. lacunae were absent) in the remaining 25 cases. When lacunae of > or = Grade 1+ were considered, the sensitivity, specificity, positive predictive value and negative predictive value of diagnosing adherent placenta were 86.9%, 78.6%, 76.9% and 88.0%, respectively. When lacunae of > or = Grade 2+ were considered, the sensitivity, specificity, positive predictive value and negative predictive value of diagnosing placenta increta or percreta were 100%, 97.2%, 93.8% and 100%, respectively. Hysterectomy was performed in 18 cases, among whom two cases showed Grade 1+ lacunae, 11 cases showed Grade 2+ lacunae, and five cases showed Grade 3+ lacunae. No hysterectomy was performed in any case in which lacunae were absent. Compared to those without lacunae, the number of massive transfusions and intensive care unit admissions and cases of disseminated intravascular coagulopathy and Cesarean hysterectomy were significantly greater in those with lacunae (P < 0.0001). CONCLUSION: Transvaginal sonographic findings of intraplacental lacunae in patients with placenta previa totalis and a history of Cesarean section are useful in the prediction of adherent placenta and may have a role in the prediction of clinical outcome.

Adult↗
PubMed2000

Hyperexpression of ICAM-1 and CD36 in placentas infected with Plasmodium falciparum: a possible role of these molecules in sequestration of infected red blood cells in placentas.

AIMS: During pregnancy, Plasmodium falciparum malaria is frequent and associated with maternofetal complications. This could be the consequence of sequestration by several adhesion molecules of parasite-infected red blood cells in syncytiotrophoblast. To investigate the expression of ICAM-1 and CD36, two of the adhesion molecules for Plasmodium falciparum, an immunohistochemical study was carried out in malaria-infected placentas. METHODS AND RESULTS: Thirty-five infected and 35 noninfected samples were chosen randomly. According to the histological classification of Bulmer, the infected placentas were separated in three groups: active, active chronic and past-chronic infection. CD36 was localized in the cytoplasm of stromal cells of terminal villi of infected or noninfected placentas, but not in syncytiotrophoblast. ICAM-1 was detected in the cytoplasm of stromal and endothelial villous cells in both infected and noninfected placentas and in syncytiotrophoblast of eight infected placentas showing more frequently active than active chronic or past-chronic infection (P < 0.001). The percentage of cells immunostained for CD36 or ICAM-1 was evaluated in the terminal villi. The proportion of villous cells, with ICAM-1 and CD36 immunostaining, was significantly higher in infected vs. noninfected placentas (P < 0.0001) and CD36 was detected more in acute inflammatory vs. past-chronic inflammatory placentas (P < 0.05). CONCLUSIONS: The higher expression of ICAM-1 in infected placentas and its localization in syncytiotrophoblast particularly during acute infection, suggest ICAM-1 can act directly in the sequestration of parasite-infected red blood cells (IRBCs). On the other hand, the expression of CD36 is influenced by the presence of IRBCs without being directly implicated in sequestration of IRBCs. The hyperexpression of these two molecules could explain the high frequency of malaria during pregnancy.

Adult↗
PubMedDate not supplied

Expression of cyclooxygenase isoforms in developing rat placenta, human term placenta, and BeWo human trophoblast model.

Cyclooxygenase (COX) catalyzes the rate-limiting step in the conversion of essential fatty acids (EFAs) to bioactive molecules such as prostaglandins (PGs), which play critical roles in many aspects of female reproduction and in fetal development. There are two primary related COX isoforms, the constitutively expressed COX-1 and the inducible COX-2. Although the expression of COX-1 and COX-2 has been demonstrated in the amnion, chorion, and decidua, relatively little information exists with regard to their expression and physiological function in the placenta during gestation. In this study, we have elucidated the spatial and temporal patterns of COX-1 and COX-2 expression in the labyrinthine and junctional zones of the developing rat placenta, in the human term placenta, and in the BeWo human trophoblast model using semiquantitative RT-PCR, Western blot, and immunohistochemical analyses. The mRNA and protein expression of COX-1 and COX-2 were demonstrated in the developing rat placenta with increasing expression observed toward parturition. COX-2 exhibited greater expression than COX-1 after mid-gestation and had a corresponding shift in spatial expression from the labyrinthine to the junctional zone at term. COX-1 and -2 were also expressed in human term placenta, while BeWo cells exhibited moderate expression of COX-1 and weak expression of COX-2. The results demonstrate that COX-1 and COX-2 are expressed in the rat and human placentas. The differential expression patterns in the rat placenta, especially of COX-2, imply that there may be gestational changes in the biosynthesis of PGs and other potential bioactive EFA metabolites. Establishing the expression of the COX isoforms provides a framework for future investigations into the functional and physiological significance of COX-1 and COX-2 in the placenta, particularly with respect to influencing normal pregnancy and fetal development, and to provide insights into therapeutic utilization of COX inhibitors in pregnancy.

Animals↗
PubMed1988

Insulin-like growth factor-I messenger ribonucleic acid in the developing human placenta and in term placenta of diabetics.

Fetal growth and development are dependent upon the growth and development of the placenta. Control of placental growth and development is little understood. Immunoreactive insulin-like growth factor-I and -II (IGF-I and IGF-II) have been shown to be released by human placental tissue and human placental membranes have been observed to contain specific receptors for these growth factors. Furthermore, we have demonstrated the presence of IGF-II mRNA transcripts in the developing human placenta and at gestational term in placentae of diabetics. Thus, the IGFs may have a regulatory role in the growth and development of the placenta via autocrine and/or paracrine mechanism(s) of action. In this report we demonstrate the presence of four differing size species of placental poly(A)+ RNA which specifically hybridize to an IGF-I probe originally isolated from an adult human liver cDNA library and localize IGF-I and IGF-II mRNA to syncytiotrophoblasts and fibroblasts, respectively, of the placenta by in situ hybridization. The major transcript is 7500 bases in size and the remaining three transcripts are 5000, 1100, and 900 bases in length with no apparent changes from these sizes throughout gestation and at term in diabetics. Quantification by densitometry of placental IGF-I mRNA detected by dot blot hybridization indicated that first and second trimester placentae each express more IGF-I mRNA relative to that expressed in placenta at term. These results suggest that there are developmental changes in the relative amount of IGF-I mRNA expressed in the human placenta. IGF-I is, therefore, most likely important early in gestation as a placental growth factor. This time period is critical for fetal development and growth, when embryonic induction, organogenesis, and rapid cell proliferation occur.

Female↗
PubMed1978

[The importance of regressive changes in the placenta during the so-called migration of the placenta (author's transl)].

Starting from the tenth to the sixteenth week of pregnancy ultrasonic placental localizations were performed in 22 pregnant women at four week intervals. In all cases the placenta was located in the anterior wall of the uterus and bordered or covered the internal os of the cervix. In 17 cases a cephalad migration of the placental localization was registered. In 5 cases the low implantation of the placenta did not change until delivery. In 14 of 19 cases marginal atrophic changes of the placenta were found. No morphologic abnormality was detected in five placentas from patients who showed migration of the placental localization. Since the placenta is tightly implanted in the endometrium a true migration of the placenta is unlikely. Our investigations show that areas of low implantation of the placenta are stretched with increasing growth of the uterus and then undergo regressive and pressure atrophy changes. It is likely that the cervical margin of the placenta cannot be detected by ultrasound in a large number of cases.

Atrophy↗
PubMed2003

Comparison of neonatal outcome including cerebral palsy between abruptio placentae and placenta previa.

OBJECTIVE: Our purpose was to evaluate the neonatal prognosis after abruptio placentae and placenta previa during pre-term gestation. STUDY DESIGN: A case-control study was performed using a logistic regression model. A poor outcome was defined as neonatal death occurring before hospital discharge or a diagnosis of cerebral palsy. RESULTS: A poor outcome was more frequent in cases of abruptio placentae (11/42, 26.2%) than in placenta previa (2/72, 2.8%) and pre-term labor (1/120, 0.8%). The difference was mainly due to the incidence of cerebral palsy. A significant association of abruptio placentae (odds ratio (OR) 61.0, 95% confidence interval (CI 3.4-1084), delivery at <31 weeks of gestation (OR 19.0, CI 2.8-128.8), and low Apgar score (<7) at 5min (OR 70.8, CI 16.5-304.9) with increased risk of poor outcome was found in the logistic regression model that controlled for confounding effects. In abruptio placentae, a low Apgar score (<7) at 5min (OR 19.8, CI 2.0-197.8) was associated with increased risk of poor outcome in the logistic regression model. CONCLUSION: From the standpoint of poor perinatal outcome including cerebral palsy, abruptio placentae was the most significant clinical entity in pre-term gestation.

Abruptio Placentae↗
PubMed1996

Translabial ultrasonography and placenta previa: does measurement of the os-placenta distance predict outcome?

The aim of this study was to assess the value of the measurement of os-placenta distance by translabial ultrasonography in the evaluation of placenta previa. This method was used in 40 women with suspected placenta previa to measure the distance between the placenta and internal cervical os. Sonographic diagnoses were compared to placental location determined at delivery. Translabial ultrasonography proved superior to the transabdominal route in both diagnosis and exclusion of placenta previa. Measurement of the os-placenta distance can be used as an adjunct to clinical assessment to predict the likelihood of safe vaginal delivery in cases of suspected placenta previa.

Adult↗
PubMed1987

Levels of epidermal growth factor binding in third-trimester and term human placentas: elevated binding in term placentas of male fetuses.

Specific binding of iodine 125-labeled epidermal growth factor was measured in membrane homogenates of third-trimester and term human placentas of male and female fetuses. All placentas (n = 35) generated curvilinear Scatchard plots, and all placentas had similar equilibrium dissociation constants for both high-affinity (210 pmol/L) and low-affinity (830 pmol/L) binding sites. Mean maximum number of available binding sites of term placentas from male fetuses (330 +/- 110 fmol/mg protein; n = 11) was significantly higher (p less than 0.001) than that of female fetuses (170 +/- 80 fmol/mg protein, n = 13). Occupation of epidermal growth factor receptors by endogenous epidermal growth factor could not account for the difference in levels of epidermal growth factor binding. Kendall's rank order correlation test demonstrated a significant positive correlation of the gestational age in weeks with the maximum number of epidermal growth factor receptors in placentas from male fetuses (p less than 0.002; T = 0.527; n = 17) and female fetuses (p less than 0.01; T = 0.404; n = 18). These results indicate that there is a sexual dimorphism in the level of epidermal growth factor receptors in placentas of male and female fetuses during the third trimester and that the level of epidermal growth factor receptors increases during the third trimester for placentas of both male and female fetuses.

Epidermal Growth Factor↗
PubMed1996

Persistent placenta increta: a complication of conservative management of presumed placenta accreta.

BACKGROUND: Recent reports have advocated conservative management rather than hysterectomy for placenta increta and its related conditions, placenta accreta and percreta. We report an unusual case of placenta increta in which initial conservative therapy for a presumed placenta accreta failed and hysterectomy was performed 6 months postpartum. CASE: A 32-year-old woman, gravida 2, para 2, was referred 5 months after a repeat cesarean delivery and bilateral tubal interruption for evaluation of an intrauterine mass. A presumed placenta accreta noted at delivery had been managed conservatively. Hysterectomy was performed, and pathologic evaluation was consistent with a retained placenta increta. CONCLUSION: Persistent placental tissue is a potential complication of conservative management of an abnormally adherent placenta.

Adult↗
PubMed2006

Sulprostone reduces the need for the manual removal of the placenta in patients with retained placenta: a randomized controlled trial.

OBJECTIVE: The purpose of this study was to determine the extent that the administration of sulprostone reduces the need for manual removal of the placenta in patients with retained placenta. STUDY DESIGN: A double-blinded sequential randomized controlled trial of sulprostone versus placebo was conducted among 103 patients with retained placenta. RESULTS: In the first phase of this sequential study, sulprostone was compared with placebo. The null hypothesis of equal effectiveness of both treatments was rejected after 50 patients. In patients with retained placenta, the placenta was expelled after sulprostone in 13 of 24 cases (51.8%, bias adjusted), whereas expulsion after placebo was achieved in only 4 of 26 cases (17.6%, bias adjusted). The difference was significant (P = .034). In the second phase of the study, in which the placebo arm was stopped, results were confirmed; in 25 of 53 patients (47%), the placenta was expelled. CONCLUSION: Sulprostone reduces the need for the manual removal of the placenta by 49%.

Abortifacient Agents, Nonsteroidal↗
PubMed2005

Risk factors for retained placenta and the effect of retained placenta on the occurrence of postpartum diseases and subsequent reproductive performance in dairy cows.

The objectives of this study were to determine the risk factors for retained placenta by evaluating several reproductive factors in individual cows, and to determine the effects of retained placenta on the occurrence of postpartum diseases and subsequent reproductive performance in dairy herds. The health status, cow parity, calving, and breeding dates were recorded from 805 calvings in nine dairy herds from October 2000 to March 2004. We used logistic regression to evaluate the effects of these factors on the incidence of retained placenta. A stepwise procedure, used to obtain the appropriate model with alpha = 0.05, revealed that abnormal partus and gestation length were important risk factors for retained placenta. The occurrence of endometritis and metabolic disorders was greater (p<0.01) in the group with retained placentas than in the control group. The mean intervals from calving to first service and conception were prolonged (p<0.05) by 7 and 18 days, respectively, in the group with retained placentas compared to the control group. These results suggest that abnormal partus and gestation length are strongly correlated with the development of retained placenta, which increases the occurrence of postpartum diseases and subsequently decreases reproductive performance in dairy herds.

Animals↗
PubMedDate not supplied

Placenta creta and placenta praevia creta.

The placental bed in placenta creta and placenta praevia creta was studied from pregnancy or immediate postpartum hysterectomy specimens. In all cases placental villi were seen in direct contact with myometrium, the sine qua non of placenta creta, but was focal in some cases. There was no apparent diminution of decidua parietalis or, in cases of focal accreta, of adjacent basalis. In all cases the extravillous trophoblast was mainly uninuclear or binuclear, in contrast to the placental bed syncytial giant cells seen in late normal placentation. There was an apparent proliferation of interstitial trophoblast at the junction of placenta with myometrium, but the density of interstitial trophoblast deeper in the myometrium was lower than it is in normal placentation. An unusual uteroplacental vasculature was seen in which physiological changes were present in large arteries of the radial/arcuate system deep in the myometrium, while there were also spiral arteries more superficially without physiological changes. These findings suggest that in placenta creta there is defective interaction between maternal tissues, particularly decidua, and migratory trophoblast in the early stages of placentation resulting in undue adherence of the placenta or penetration into the uterus coupled with the development of an abnormal uteroplacental circulation.

Arteries↗
PubMed1983

Rh immunoglobulin use with placenta previa and abruptio placentae.

Patients with obstetric hemorrhage from placenta previa or abruptio placentae may be at increased risk of Rh sensitization because they fail to receive Rh immunoglobulin (RhIG) or are given an inadequate dose. To evaluate the use of RhIG in this clinical situation, we studied 498 patients with hemorrhage from placenta previa or abruptio placentae treated at a large municipal hospital from 1975 to 1979. All 25 RhIG candidates received the product before their discharge from the hospital. This rate of RhIG use was equal to that for patients whose infants were delivered without these complications and significantly higher than that for patients with spontaneous abortion and ectopic pregnancy at the same hospital (P less than .05). Prompt administration of an adequate dose of RhIG to candidates with bleeding from placenta previa or abruptio placentae can further reduce Rh hemolytic disease.

Abortion, Spontaneous↗
PubMed2006

Expression of kallikrein, bradykinin b2 receptor, and endothelial nitric oxide synthase in placenta in normal gestation, preeclampsia, and placenta accreta.

In an effort to define the varied expression of three vasoactive markers in the clinical models of normal placenta/ normal invasion (n = 11), preeclampsia/restricted trophoblast invasion (n = 15), and placenta accreta/exaggerated invasion (n = 6), we performed semiquantitative immunohistochemistry for kallikrein, bradykinin B2 receptor, and endothelial nitric oxide synthase (eNOS). In the floating villi, the syncytiotrophoblast expressed more kallikrein in placenta accreta (p < 0.05), than in normal and preeclamptic placentas, while the bradykinin B2 receptor and eNOS were similarly expressed in all groups; in the fetal endothelium, the bradykinin B2 receptor was enhanced in placenta accreta (p < 0.005), but kallikrein and eNOS were similarly expressed in the other two groups. In the extravillous trophoblast, both kallikrein and eNOS expression were higher in placenta accreta (p < 0.001), while the bradykinin B2 receptor signal was only enhanced in preeclampsia (p < 0.05). The presence and localization of kallikrein, the bradykinin B2 receptor, and eNOS in the fetomaternal interface in the three study conditions supports a local role for interrelated vasodilatory/antiaggregating systems. This first report of the variations observed in kallikrein and eNOS in a condition of exaggerated trophoblast invasion supports the participation of vasodilatation in trophoblast migration.

Chorionic Villi↗