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PubMed1998

Parathyroid hormone-related protein (PTHrP) mRNA splicing and parathyroid hormone/PTHrP receptor mRNA expression in human placenta and fetal membranes.

During human pregnancy, parathyroid hormone-related protein (PTHrP) and parathyroid hormone (PTH)/PTHrP receptor are produced by the uterus, placenta, fetal membranes (amnion and chorion) and developing fetus. PTHrP alternative 3' mRNA splicing results in transcripts which encode three PTHrP isoforms and have been identified in amnion. Uteroplacental PTHrP expression is greatest in amnion and increases dramatically during late pregnancy. The aims of this study were to determine PTH/PTHrP receptor mRNA expression at preterm and term gestations and to determine 3' alternative splicing patterns in placenta, amnion and choriodecidua at preterm and term gestations. Using semiquantitative reverse transcription-polymerase chain reaction, PTHrP and PTH/PTHrP receptor transcripts were identified in preterm (n=5) and term (n=7) gestational tissues. PTH/PTHrP receptor mRNA expression did not differ between tissue types or change with advancing gestation. In contrast, PTHrP expression in the same tissues increased with advancing gestation and was significantly greater in amnion than in placenta and choriodecidua. Thus PTHrP, although produced predominantly in amnion, may act in amnion and other tissues including placenta, choriodecidua and myometrium. In amnion over placenta, transcripts encoding PTHrP 1-139 and 1-173 were detected in some preterm and all term samples and those encoding PTHrP 1-141 were detected in all samples. Similar results were obtained for reflected amnion. In placenta and choriodecidua, PTHrP 1-139 and 1-173 transcripts were undetectable or of low abundance. PTHrP 1-141 transcripts were detected in some placenta and choriodecidua samples. In summary, transcripts encoding PTHrP 1-141 appeared to be more abundantly expressed than those encoding PTHrP 1-139 or 1-173. However, the up-regulation of PTHrP expression in amnion at term may involve each of the alternative 3' mRNA splicing pathways since transcripts for each isoform appeared to be more consistently expressed at term.

Alternative Splicing↗
PubMed1987

Potential placenta previa: definition, frequency, and significance.

Sixty-three (5%) of 1239 women studied by sonography during the second trimester of their pregnancies had a diagnosis of placenta previa. Follow-up was available for 51 of the 63 patients; in three of these, the original diagnosis was complete placenta previa, and in the other 48, the first diagnosis was partial or marginal placenta previa. At term, placenta previa was seen in only four patients for an overall frequency of 0.3% (4/1227). In all three of the patients with complete placenta previa, the condition persisted from the second trimester to term; previa persisted in only one of 48 patients with marginal/partial previa. Because of the infrequent persistence of marginal or partial placenta previa to term, we recommend using the term "potential placenta previa" in the second trimester, with follow-up sonography indicated only for vaginal bleeding.

Female↗
PubMed1997

Risk of retained placenta: multivariate approach.

BACKGROUND: To identify important covariates related to retained placenta using logistic regression analysis. METHODS: The study was carried out in the King Khalid University Hospital, Saudi Arabia, and involved 114 women who had retained placenta, and 116 women with normal deliveries. Chi-square test and logistic regression analysis were used for analysis of data. Adequacy of predictor variables was examined using indices of sensitivity and specificity and plots of probability histograms for prediction of retained placenta among patients and controls. RESULTS: Logistic regression analysis highlighted multiparity, induced labor, small placenta, and large amount of blood loss to be significantly associated with retained placenta. In addition, high pregnancy number, previous injury to uterus, and pre-term labor related significantly to retained placenta. Predictor variables had sensitivity of 65.5% and 87.9% specificity and achieved 77% overall correct classification. CONCLUSIONS: These findings could be used to develop a predictive procedure for identifying high-risk cases of retained placenta.

Case-Control Studies↗
PubMed1999

Feasibility of autologous blood donation in patients with placenta previa.

BACKGROUND: Debate continues as to whether autologous blood donation is feasible in patients with placenta previa. A recent study in a university setting concluded that routine autologous donation in patients with placenta previa is not indicated. In our study we assessed the feasibility of autologous blood donation for patients with placenta previa in a community-hospital setting. METHODS: We performed a chart review over a 5-year period of all patients admitted with placenta previa. A theoretical model was then applied to this data. To be eligible for autologous donation, the patient would need to be asymptomatic and have a hemoglobin level of 11 gm/dL or higher at 32 weeks' gestation. RESULTS: Fifty-nine patients were admitted with uncomplicated placenta previa, 34% (20) of whom were eligible for autologous donation. We found that 20% (4) of patients who met eligibility criteria for autologous blood donation would have benefitted from predonation, and 10% (2) of patients meeting eligibility criteria might have become anemic at delivery because of the donation. CONCLUSIONS: Autologous donation is not feasible in most patients with placenta previa. However, the proportion of patients eligible for autologous blood donation in a community-hospital setting is 2.5 times the proportion of eligible donors in a university hospital setting (P = .003). Asymptomatic patients with placenta previa diagnosed by 32 weeks, who have a hemoglobin level of 11 gm/dL or above, may be safely offered this option.

Adult↗
PubMed1998

Superoxide dismutase activity in normal and preeclamptic placentas.

OBJECTIVES: A deficiency in superoxide dismutase (SOD) activity in preeclamptic placentas can lead to an excess of superoxide radicals and may be responsible for the development and the severity of preeclampsia (PE). DESIGN: Our studies were undertaken in order to determine placental SOD activity and to investigate their association with the development and the severity of PE. MATERIALS AND METHODS: The activity of SOD was determined using a spectrophotometric method in 22 placentas from normal term pregnancies (group K), 24 placentas from pregnancies complicated by severe PE (group PE), and 21 placentas from pregnancies complicated by severe PE and intrauterine growth retardation (IUGR) (group PEI). RESULTS: Mean activity of SOD (MSOD) in 45 preeclamptic placentas 3.89 +/- 1.32 (M +/- SD) was significantly lower (P = 0.008) as compared to MSOD in the group K (6.75 +/- 1.96). MSOD in the PEI group (3.5 +/- 1.29) was significantly lower (P = 0.03) as compared to MSOD in the group K. MSOD in the PE group (4.23 +/- 1.25) was lower than MSOD in the group K, but this difference was not statistically significant (P = 0.11). MSOD in the group PEI was lower as compared to MSOD in the PE group, however this difference was not statistically significant (P = 0.23). CONCLUSIONS: The studies revealed decreased SOD activity in preeclamptic placentas in comparison to normal placentas.

Adult↗
PubMed1999

Effects of dopamine and melatonin on the regulation of the PIT-1 isotype, placental growth hormone and lactogen gene expressions in the rat placenta.

Rat placenta produces several members of the placental prolactin-growth hormone (PRL-GH), including placental lactogen (PL) and placental prolactin like protein (PLP), during pregnancy. It is important to study placental local regulators that control the expression of PRL-GH genes. We have previously reported that dopamine (DA) can regulate Pit-1 and PL-II gene expressions. In this study we aimed to investigate the local expression of melatonin receptor 1a (Mel1a) and the effects of DA and melatonin on the expressions of PL-Iv, PL-II, PLP-C genes and Pit-1 gene that are involved in the expression of PRL-GH genes in the rat pituitary and placenta. According to the Northern blot analysis, DA receptor 2 (D2) was expressed in the rat placenta. We also report on the local expression of Mel1a in the rat placenta for the first time. Injected DA agonist, bromocriptine (in vivo) decreased PL-Iv, PLP-C and Pit-1 mRNA levels in the rat placenta. The melatonin agonist, chloromelatonin in culture media also decreased the levels of PL-Iv, PL-II and PLP-C mRNA. However, melatonin does not affect the Pit-1 mRNA level. These data suggest that D2 and Mel1a may control the expression of PRL-GH genes in the rat placenta and its response to the extracellular changes of DA and melatonin secreted from the maternal organ. However, Pit-1 may not be involved in the Mel1a induced inhibition of PRL-GH gene expressions in the rat placenta.

Animals↗
PubMed2000

Nutrients and hormones in heat-dried human placenta.

This cross-sectional study was to assess the nutrients in terms of protein, fat, minerals, and hormones in heat-dried human placenta. Thirty heat-dried human placentas, 15 from male and 15 from female, were analyzed for protein (amino acids), fiber, fat, moisture, minerals (sodium, potassium, phosphorus, calcium, iron, magnesium, zinc, copper, manganese), hormones (estradiol, progesterone, testosterone, growth hormone). Heat-dried female human placentas had slightly higher fiber content than male, but protein and fat components were not different. Mineral levels in placentas were high especially sodium, potassium and phosphorus. There were no significant differences in the amount of minerals and hormonal profile between female and male placentas. However, hormone levels in heat-dried placenta were low compared to physiologic level in human beings. The results of this study suggest that the amount of nutrients particularly protein and minerals in heat-dried human placentas were enriched.

Amino Acids↗
PubMed2001

Placenta increta/percreta associated with uterine perforation during therapy for fetal death. A case report.

BACKGROUND: Placenta accreta involves abnormal adherence of the placenta to the myometrium. Placenta increta and percreta are defined by the degree of trophoblastic penetration of the myometrium. These conditions are rarely observed in the first trimester; placenta increta and percreta are exceptionally infrequent. CASE: A woman had a uterine perforation after suction curettage for fetal death at 11 weeks' gestation, requiring hysterectomy for control of a profuse hemorrhage. Histopathologic examination of the uterus revealed placenta increta involving the lower uterine segment and placenta percreta at the site of uterine perforation. CONCLUSION: This is the first report of placenta percreta associated with uterine perforation during therapy for first-trimester fetal death.

Adult↗
PubMed2001

Morphologic and histopathologic characteristics of placentas from twin pregnancies spontaneously conceived and from reduced and nonreduced assisted reproductive technologies.

OBJECTIVE: To prospectively evaluate morphologic and histopathologic characteristics of placentas from twin pregnancies obtained by assisted reproductive technologies (ART) and non-ART and to evaluate the influence of previous fetal reduction on placental features. STUDY DESIGN: Fifty-five placentas from consecutive deliveries of ART-obtained and 50 placentas from consecutive deliveries of non-ART-conceived twin pregnancies were investigated by one pathologist, who was blinded to specimen origins. The patients' demographic and clinical data were also recorded. RESULTS: The mean maternal and gestational ages were similar in both groups. ART-obtained pregnancies were associated with an increased incidence of pregnancy complications and lower mean birth weight. Placentas from ART-obtained pregnancies were mostly of the dichorionic type and were thinner, weighed less and had more infarctions as compared to non-ART-conceived pregnancies. Placental characteristics of reduced ART-obtained twin pregnancies were comparable to those of nonreduced ones. The second twin's placenta in all groups weighed less and had a higher incidence of anomalous umbilical cord insertion. CONCLUSION: Placentas from ART-obtained twin pregnancies appear to have more pathologic features as compared to those of non-ART-conceived ones. Fetal reduction does not significantly affect the remaining placentas.

Case-Control Studies↗
PubMed2001

[Assessment of lipid peroxidation intensification in normal and preeclamptic placentas].

OBJECTIVE: Free radical induced lipid peroxidation (LP) in the placenta has been suggested as a possible pathogenetic factor of preeclampsia (PE). DESIGN: The aim of the study was to assess LP intensification by the measurement of lipid peroxidation products (LPP) content in placentas from normal and preeclamptic pregnancies. MATERIALS AND METHODS: The investigations comprised placentas obtained immediately after delivery from 24 normal pregnancies [group K], 26 pregnancies complicated by severe PE without intrauterine growth restriction (IUGR) [group PE] and 23 pregnancies complicated by severe PE and IUGR [group PEI]. LPP content was measured by the quantitative determination of thiobarbituric acid reactive substances (TBA-RS) amounts in studied placentas. Used TBA test was calibrated with malondialdehyde (MDA) and results were expressed as MDA equivalent in nmol/mg protein. Comparative analysis was performed using U Mann-Whitney and median tests. RESULTS: Mean placental level of LPP (MLPP) in the group PE-2.45 +/- 0.39 (M +/- SD) was significantly higher (p < 0.001) as compared to MLPP in the group K (1.58 +/- 0.24). MLPP in the PEI group (2.81 +/- 0.65) was higher (p < 0.001) than MLPP in the group K as well as MLPP in the group PE but statistical significance of the latter difference was lower (p = 0.032). CONCLUSIONS: The intensification of LP in placentas from pregnancies complicated by severe PE is IUGR dependent and higher than in placentas from normal pregnancies. Obtained results may indicate that higher degree of LP intensification in preeclamptic placentas may be involved in PE pathogenesis.

Adult↗
PubMed2001

[DNA adducts level in normal and preeclamptic placentas].

OBJECTIVE: An increase in lipid peroxidation intensification in preeclamptic placentas leads to an increased level of lipid peroxidation products and increased reactive oxygen species activity which can be associated with increased activation of chemicals to electrophilic species that bind covalently to DNA and form adducts. DESIGN: The aim of the study was the determination of DNA adducts (A-DNA) in placentas from normal and preeclamptic pregnancies. MATERIALS AND METHODS: The investigations comprised placentas obtained immediately after delivery from 21 normal pregnancies [group K], 24 pregnancies complicated by severe preeclampsia-PE without intrauterine growth restriction (IUGR [group PE] and 21 pregnancies complicated by severe PE and IUGR [group PEI]. DNA adducts were determined using nuclease P1 digestion enhancement version of the 32P-postlabeling method. The results were expressed in numbers of DNA adducts per 10(8) nucleotides. Comparative analysis was performed using ANO-VA and median tests. RESULTS: Mean level of A-DNA (MA-DNA) in the group PE--1.39 +/- 1.21 (M +/- SD) was similar (p = 0.57) to MA-DNA in group K (1.16 +/- 1.03). However MA-DNA in the PEI group (1.93 +/- 1.28) was significantly higher (p = 0.045) than MA-DNA in the group K as well as MA-DNA in the group PE (p = 0.025). MA-DNA level in all studied preeclamptic placentas (groups PE + PEI) was 1.65 +/- 1.26 and was similar (p = 0.152) to revealed in group K. CONCLUSIONS: The level of DNA adducts in placentas from pregnancies complicated by severe preeclampsia and IUGR is higher than in placentas from pregnancies complicated by severe preeclampsia without IUGR and higher than in placentas from normal pregnancies.

Adult↗
PubMed2001

The retained placenta.

The retained placenta is a significant cause of maternal mortality and morbidity throughout the developing world. It complicates 2% of all deliveries and has a case mortality rate of nearly 10% in rural areas. Ultrasound studies have provided fresh insights into the mechanism of the third stage of labour and the aetiology of the retained placenta. Following delivery of the baby, the retro-placental myometrium is initially relaxed. It is only when it contracts that the placenta shears away from the placental bed and is detached. This leads to its spontaneous expulsion. Retained placenta occurs when the retro-placental myometrium fails to contract. There is evidence that this may also occur during labour leading to dysfunctional labour. It is likely that this is caused by the persistence of one of the placental inhibitory factors that are normally reduced prior to the onset of labour, possibly progesterone or nitric oxide. Presently, the only effective treatment is manual removal of placenta (MROP) under anaesthetic. This needs to be carried out within a few hours of delivery to avoid haemorrhage. For women in rural Africa, facilities for MROP are scarce, leading to high mortality rates. Injection of oxytocin into the umbilical vein has been suggested as an alternative. This method relies on the injected oxytocin passing through the placenta to contract the retro-placental myometrium and cause its detachment. Despite several placebo controlled trials of this technique, no firm conclusion have been reached regarding its efficacy. This may be due to inadequate delivery of the oxytocin to the placenta. Further trials are in progress to assess the optimal dose of oxytocin as well as the efficacy of a new technique designed to improve delivery of the oxytocin to the placental bed.

Female↗
PubMed1992

[The course of pregnancy with placenta praevia diagnosed in the 2nd and 3rd trimester].

Selected clinical features of the course of pregnancy in 118 gravidas with placenta praevia diagnosed ultrasonographically on the first breeding were compared. The clinical features significantly connected with bleeding and the prognostic features for the way of delivery were stated. The longest bleeding was observed in patients with partial or marginal placenta praevia. The most common anterior location of low placenta praevia was connected with the lowest risk as regards the cesarean section due to hemorrhage. The earlier occurrence of the bleeding was associated with its longer duration. The time of the occurrence of the first bleeding and its duration were associated with a duration of the pregnancy and a body mass of the newborn. The recurrence of bleeding was of no prognostic importance. The appearance of the first bleeding after the 28th week of pregnancy was significantly connected with the necessity of performing a cesarean section due to hemorrhage in case of central, partial or marginal placenta praevia. In case of low-lying placenta the way on delivery was significantly related to the time of appearance of the first bleeding and the distance between the placenta and the internal os. Fisher's linear discriminative function of the two features allowed for the determination of a mathematical formula for the prognosis of the way of delivery in case of a low-lying placenta.

Adolescent↗
PubMedDate not supplied

Perfusion of human term placentas with lipopolysaccharide did not affect the capacity of the fetal and maternal tissues to produce interleukin-10.

IL-10 is anti-inflammatory cytokine that is involved in the regulation of the pregnancy process. We examined the capacity of fetal and maternal placental tissues from human term placentas, to produce IL-10, in the presence and absence of LPS. The levels of IL-10 were examined (by ELISA and immunohistochemical staining) in the fetal and maternal tissues of human placentas after 10 hours of perfusion, in the presence or absence of lipopolysaccharide (LPS; 1 microg/k"g perfused tissue). We could detect IL-10 in amnion (A; 13.91+/-11.35 pg/ml) and chorion (CH; 7.85 +/- 6.38 pg/ml) tissue homogenates, and in the homogenates of three different sites of the placental tissue compartment (subchorionic placenta (SubCH); 7.39 +/- 4.39 pg/ml, mid-placenta (MidPL); 8.9 +/- 4.73 pg/ml and decidua (Decid); 16.48 + 11.86 pg/ml). Immunohistochemical studies showed that IL-10 was localized in the epithelial cells of the amnion, and in the fibroblasts and macrophages of the chorion. In the placenta and mid-placental sites, IL-10 is localized mainly in cytotrophoblasts and syncytotrophoblasts. The presence of LPS in the perfusion media of the placentas for 10 hours, did not significantly affect the capacity of the fetal and maternal tissues to produce IL-10. Thus, our results may indicate the involvement of the fetal compartment in the down-regulation of the cell-mediated response of the maternal compartment against the fetus, by producing IL-10 under physiological conditions. Infection/inflammation agents such as LPS did not affect the expression levels of IL-10 in the placenta.

Female↗
PubMed2004

Placenta previa and it's relation with maternal age, gravidity and cesarean section.

The placenta provides the essential connection between the mother and the developing fetus. Placental position were routinely mentioned in an ultrasound report starting from early second trimester to the end of third trimester when asked for pregnancy evaluation. The aim of this study was to see the prevalence of lower segment placenta (placenta previa) and its relations with previous cesarean section delivery, parity and maternal age. The study conducted in Centre for Nuclear Medicine and Ultrasound (CNMU) Mymensingh in a period from January 2001 to December 2002. About 2536 pregnant women (those included in this study) underwent ultrasound examination during pregnancy at third trimester. The prevalence of lower segment placenta was 1.34%. The highest prevalence of placenta previa (2.58%) was seen in 3rd and higher gravida group. Also the highest prevalence were seen 30 yr. and above age group in compare to below 30 yr. age group. No increased prevalence of placenta previa were seen in previous cesarean section (C / S) delivery group (0.65%) in compare to normal delivery group (1.97%). From our study it was seen that development of lower segment placenta has relation with increased number of gravidity and maternal age but no increased prevalence were seen in subjects with previously done cesarean section

Adult↗
PubMed2004

The occurrence of abruptio placentae in Canada: 1990 to 1997.

Abruptio placentae is a serious obstetric condition associated with an increased incidence of perinatal mortality and morbidity. Despite this, there is little information on the occurrence of abruptio placentae in Canada. The Discharge Abstract Database from the Canadian Institute for Health Information was used to identify a cohort of women who had singleton live or stillbirth deliveries in Canada between 1990 and 1997 (n = 2,162,815). Rates of abruptio placentae and abruptio placentae ending in stillbirth were examined by calendar year, province, maternal age and urban/rural status. There is a trend towards an increasing rate of abruptio placentae by year, from 10.9 (95 % confidence interval [CI] 10.5-11.3) cases/1000 deliveries in 1990 to a high of 12.1 (95% CI 11.6-12.5) cases/1000 deliveries in 1996, while the rate ending in stillbirth remained relatively constant. The abruptio placentae rate was highest in mothers over 40 years of age and the case-fatality rate highest in those under 20. These results provide a baseline reference for rates of abruptio placentae in Canada.

Abruptio Placentae↗
PubMed2002

[To identify human and sheep placentas by FT-IR and RP-HPLC techniques].

Placenta has a long history of being Chinese traditional medicine. The quality control methods used nowadays in the markets were mainly based on the amino acid content of the placenta. However, it is hard to distinguish human placenta from sheep placenta with these methods. In this paper, a novel method was established employing FT-IR and RP-HPLC techniques. This method can distinguish human placenta from sheep placenta and may help to improve quality control of placenta in the markets.

Amino Acids↗
PubMed2004

Pyruvate kinase activity in the placentas of women living in polluted and unpolluted environments.

BACKGROUND: It was shown earlier that in women living in a polluted environment, the proportion of hypotrophic newborns was greater than in the general population. The placentas of these women show significant histological changes. The authors decided to check whether the activity of pyruvate kinase (PK), a key enzyme in the third stage of glycolysis, changes similarly. MATERIAL/METHODS: The study was conducted on placentas collected from women who had lived in a polluted environment (Groups I and II) and those who had inhabited an unpolluted area (Group III) while pregnant. RESULTS: Total PK activity and the specific activities of its isoenzymes were measured according to the Bücher and Pfleiderer method. The isolation of PK isoenzymes was carried out following the previously described procedure. Total PK activity was lower in the placentas of women of Groups I and II than in those of Group III. The presence of two PK isoenzymes, M2 and L, was demonstrated. The M2 and L isoenzymes from the placentas of Groups I and II had a lower specific activity than those of Group III. Only one form of the M2 isoenzyme and the L dephospho-isoenzyme in the placentas from Groups I and II was observed, while in placentas of Group III women both forms of the M2 isoenzyme and the L phospho-isoenzyme were noted. CONCLUSIONS: It is possible that the presence of the two PK isoenzymes in the placenta ensures the production of a sufficient amount of pyruvate.

Air Pollution↗