Advanced ultrasonic placental maturation in twin pregnancies

The mean length of twin pregnancies is shorter than that of singleton pregnancies. The possibility that the shorter gestation of twins is associated with advanced fetal maturational changes was studied in relation to placental maturation. For this purpose, the sonographically determined placental gradings of 158 twin pregnancies and 474 singleton pregnancies were compared at different gestational ages. The percent distributions of placental grades, from I to III, were significantly different throughout the third trimester, with a preponderance of Grade III placentas in the twin group (p less than 0.001). Considering the reported association of Grade III placentas with advanced gestation as well as fetal lung maturity, the present study suggests earlier maturational changes in twin fetuses compared with singleton fetuses.     

Placental apoptosis in pregnancies with intrauterine meconium passage

In this study we investigated the presence of placental apoptosis in pregnancies with intrauterine meconium passage. Placental tissue samples at term were obtained from 15 normal and 15 pregnancies with intrauterine meconium passage. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling method was applied to confirm apoptosis in all placental samples. The mean apoptotic ratio was significantly higher in placentas of pregnancies with intrauterine meconium passage when compared with normal ones (0.37 +/- 0.06% and 0.29 +/- 0.07%, respectively; p < 0.01). The mean apoptotic ratios in trophoblastic and stromal cells were significantly higher in placentas of pregnancies with intrauterine meconium passage than normal placentas (0.47 +/- 0.10% and 0.36 +/- 0.11% [ p < 0.05] and 0.29 +/- 0.07% and 0.22 +/- 0.07% [ p < 0.05], respectively). Increased placental apoptosis in pregnancies with intrauterine meconium passage could be a causative factor in the pathophysiology of the disorder or a direct effect of meconium on placental cells.     

Trophoblast apoptosis in human term placentas from pregnancies complicated with idiopathic intrauterine growth retardation

Objective.?To investigate proliferative, apoptotic, and antiapoptotic activity of placental trophoblast in pregnancies complicated with idiopathic intrauterine growth retardation (IUGR).

Methods.?Study group included data and placentas from 52 normal singleton term pregnancies with idiopathic IUGR. Records and placentas from 69 singleton pregnancies with normal fetal growth served as a control group. IUGR was defined by birth weight less than 10th percentile of standard values. Children with congenital malformations and those born with the signs of hypoxia, laboratory or clinical signs of preeclampsia or infection, children born to anemic mothers and those born from pregnancies with an increased coagulation system activity were excluded.

Results.?There was no statistically significant difference in the cytotrophoblast proliferation index value (Z?=?0.24; P?=?0.553), trophoblast expression of the Bcl-2 antiapoptotic factor (Z?=?0.47; P?=?0.634), and trophoblast apoptotic index (Z?=?0.51; P?=?0.613) between the idiopathic IUGR and control group.

Conclusion.?The proliferative and apoptotic events in the trophoblast of placentas with idiopathic IUGR did not differ from physiologic ones. Study results suggest the IUGR syndrome to have no uniform etiology or even underlying pathophysiology that would determine the possible fetal risk and subsequent long-term consequences for fetal health and life. This imposes the need of a more precise definition and unambiguous distinction between the idiopathic and other forms of IUGR.     

Obstetric outcomes of elderly primiparous singleton pregnancies conceived by <Emphasis Type="Italic">in vitro</Emphasis> fertilization compared with those conceived spontaneously

Aim:  To examine the obstetric outcomes of elderly primiparous singleton pregnancies conceived by in vitro fertilization (IVF) compared with those conceived spontaneously.
Methods:  Data were collected from primiparous women aged 35 years and older with a singleton pregnancy conceived by IVF ( n  = 89) or spontaneously ( n  = 849). Data included antenatal data, gestational age at delivery, obstetric complications, such as pregnancy-induced hypertension, gestational diabetes, placental previa and placental abruption, mode of delivery, birth weight, fetal demise and the Apgar score at 1 min.
Results:  The elective Cesarean rate in pregnancies following IVF was significantly higher than that in the control group ( P =  0.014). However, there were no significant differences in obstetric outcomes between the two groups.
Conclusions:  The current results did not support the IVF-related risks of elderly primiparous singleton pregnancies. (Reprod Med Biol 2007; 6: 219–222)     

Does cyclic human chorionic gonadotropin secretion indicate embryo loss in in vitro fertilization?

The human chorionic gonadotropin (hCG) beta subunit curve of normal singleton in vitro fertilization (IVF) pregnancies shows cyclic peaks during the first 56 days after embryo transfer (ET). This phenomenon is not demonstrable in normal spontaneous conceptions. The hCG curves of 151 singleton IVF pregnancies achieved by transfer of two, three, and four embryos therefore were compared statistically with the hCG curves of singleton IVF pregnancies achieved by transfer of only one embryo. The hCG levels of singleton IVF pregnancies achieved by transfer of more than one embryo had statistically higher hCG levels at 7 and 8, 19 and 20, and 37 and 38 days after ET. In a separate evaluation it was observed that declines in hCG levels of normal singleton IVF pregnancies preceded four of five first-trimester abortion incidence peaks of singleton IVF pregnancies. The observed cyclic hCG secretion may be indicative of early embryo deaths. This observation supports the contention that multiple ET results in significantly more multiple implantations than previously appreciated. Thus embryo survival in utero may represent another major contributory factor to success or failure of IVF.     

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.     

Mode of conception,placental morphology and perinatal outcome of twin gestations

OBJECTIVE: To compare the perinatal outcome and placental morphology of twins conceived by assisted reproductive technologies (ART) or natural conception (NC). METHODS: The present retrospective study included 88 twin pairs. Methods of ART included in vitro fertilization, intrauterine insemination, embryo transfer and induced ovulation. Placental morphology was described by chorionicity, amnionicity, placental weight, umbilical cord insertion and the number of cord vessels. Perinatal outcomes included maternal age, gestational age, birth weight (BW), BW discordance and mode of delivery. RESULTS: The mothers of ART twins were 4 years older than NC mothers. ART twins delivered 2.2 weeks earlier than NC twins. The BW of ART twins A and B were less than NC twins A and B. There was no difference in the proportion of discordant twins in either group. Dichorionic diamniotic (DD) placentas accounted for the majority of placentas in both groups. There were no monochorionic-monoamniotic placentas in ART pairs, but there were 2.9% in NC pairs. Mode of conception had no effect on placental weight in DD or monochorionic-diamniotic twins in either group except for larger DD fused placentas in the ART group. CONCLUSION: ART twin pairs were delivered at an earlier gestational age at lower birth weights to older mothers predominantly by cesarean section. This perinatal outcome was not reflected by placental morphology.     

Villous histomorphometry and placental bed biopsy investigation in Type I diabetic pregnancies

Insulin-dependent diabetes mellitus (Type I) is associated with disregulation of the glucose and oxygen metabolic pathways during pregnancy, both of which affect placental villous development. Term complete placentas and placental bed biopsies, between 37 and 40 weeks, from 12 singleton pregnancies complicated by Type I diabetes were collected following delivery by elective Caesarean section. The controls consisted of 10 term placentas from uncomplicated pregnancies delivered by elective Caesarean section. Villous morphology was investigated using unbiased histomorphometric techniques, in relation to the degree of transformation of the spiral arteries and the presence of fetal macrosomia. A significant increase in fetal and placental weights, placental volume, volumes of the intervillous space and the trophoblast was found in the diabetic group compared to the controls. A significant reduction in the villous membrane specific diffusing capacity was observed between the diabetic and control groups (1.32 vs 1.72 cm3 min(-1)mmHg(-1)kg(-1), P=0.032). A significant increase in the volume of the intermediate and terminal villi, the surface area of the villi and of the fetal capillaries, and the harmonic thickness of the villous membrane was found in the macrosomic subgroup compared to the controls. There were no differences between the hypertensive subgroup with histological evidence of partial transformation of the spiral arteries and the controls. These data indicate that placental development in insulin-dependent diabetic pregnancies is affected differentially when pregnancies complicated by fetal macrosomia are separated from those complicated by maternal hypertensive disorders with partial transformation of the spiral arteries. The reduction in the specific diffusing capacity of the villous membrane may contribute to the fetal hypoxia and increased fetal and neonatal morbidity associated with diabetes.     

Placental findings in low-risk, singleton, term pregnancies after uncomplicated deliveries

Should all placentas be sent to pathology for examination after delivery room triage? A cohort of 88 placentas was prospectively obtained and examined from low-risk, singleton, term pregnancies after uneventful delivery. All patients had a normal prenatal testing and anatomy ultrasound. Fifty-one placentas (58%) were normal. Thirty-seven of the placental cohort (42%) had abnormal findings. Thirteen of the abnormal placentas (35.1%) showed pathology unassociated with fetal compromise. Twenty-four of the placentas (27.3% of the total cohort and 64.9% of the abnormal placentas) showed findings associated with fetal compromise. The most common pathologies were marginal cord insertion, chorioamnionitis, and abruption. Routine placental examination is not indicated, according to our data, in low-risk, singleton, and term pregnancy unless the placenta is determined to be abnormal at delivery examination.     

Reduced fetal platelet counts in pregnancies with abnormal Doppler umbilical flow waveforms

Fetal and maternal platelet counts were correlated with antenatal assessment of the umbilical-placental waveform. Forty singleton pregnancies were studied using Doppler ultrasound, and placental resistance was categorized as normal or high according to the systolic/diastolic ratio. We performed platelet counts on maternal and cord blood taken at the time of cesarean section. The high-resistance group had a mean fetal platelet count (218 +/- 53 x 10(3)/microliters) significantly lower than that of the normal-resistance group (314 +/- 76 x 10(3)/microliters) (P less than .001). This difference was evident in both the hypertensive and nonhypertensive subgroups of the high-resistance group. There was no difference in mean maternal platelet counts between the high- and normal-resistance groups.     

The costs to the NHS of multiple births after IVF treatment in the UK

OBJECTIVES: To determine the cost to the NHS resulting from multiple pregnancies arising from IVF treatment in the UK, and to compare those costs with the cost to the NHS due to singleton pregnancies resulting from IVF treatment. DESIGN: A modelling study using data from published literature and cost data from national sources in the public domain, calculating direct costs from the diagnosis of a clinical pregnancy until the end of the first year after birth. SETTING: Academic Unit of Reproductive and Developmental Medicine. POPULATION: Theoretic core modelling study using data from published literature. METHODS: The analysis was based on the total annual number of births resulting from an IVF treatment in the UK. Main outcome measures total direct costs to the NHS per IVF singleton, twin or triplet family. MAIN OUTCOME MEASURES: Cost of singleton, twin and triplet IVF pregnancies in the UK. RESULTS: Total direct costs to the NHS per IVF twin or triplet family (maternal + infant costs) are substantially higher than per IVF singleton family (singleton: pounds 3313; twin: pounds 9122; and triplet: pounds 32,354). Multiple pregnancies after IVF are associated with 56% of the direct cost of IVF pregnancies, although they represent less than 1/3 of the total annual number of maternities in the UK. CONCLUSIONS: Multiple pregnancies after IVF are associated with high direct costs to the NHS. Redirection of money saved by implementation of a mandatory 'two embryo transfer' policy into increased provision of IVF treatment could double the number of NHS-funded IVF treatment cycles at no extra cost. Further savings could be made if a selective 'single embryo transfer' policy were to be adopted.     

Monochorionic twins with unequal placental sharing: why can the outcome still be favorable?

Objective: In monochorionic diamniotic (MCDA) twin pregnancies, unequal placental sharing does not always lead to adverse outcomes. The aim of this study is to investigate how unequal placental sharing may be compensated by placental anatomical changes.

Methods: Between January 2012 and July 2013, a total of 60 uncomplicated MCDA pregnancies ending in live birth of healthy twins were studied. Placentas were divided into two groups; an equally shared placenta group (placenta territory discordance ≤25%, N?=?40) and an unequally shared placenta group (placenta territory discordance >25%, N?=?20). Angioarchitecture, cord insertion type and the distance between two cord insertions were compared.

Results: Vascular anastomoses were seen in all 60 placentas, and 58 placentas (96.7%) had arterioarterial anastomoses (AA). The overall diameter of the AA was larger in the unequally shared placenta group as compared to the equally shared placentas (0.27?±?0.12?cm versus 0.19?±?0.1?cm, p?<?0.05). The distance between the cord insertions was shorter in the unequally shared group (14.5?±?6.0?cm versus 18.3?±?6.5?cm, p?<?0.05).

Conclusion: The absence of adverse outcomes in unequally shared placenta group can be explained by the presence of large AA and shorter distance between cord insertions, protecting the twin with the smaller placental part against growth restriction and other pathology.     

Placental abnormalities associated with isolated single umbilical artery in small-for-gestational-age births

BackgroundPrevious studies have shown that pregnancies complicated by placentas with an isolated single umbilical artery (iSUA) are at increased risk for small-for-gestational-age (SGA) births. The etiology of SGA in this population, however, remains unknown.ObjectiveThe primary objective of this study was to evaluate whether placental abnormalities in pregnancies with SGA births differ according to the presence of iSUA.Study designThis was an observational study of all women with pathologic examination of the placenta after delivering a non-anomalous, singleton SGA neonate between January 2009 and August 2015. SGA was defined as birthweight less than 10th percentile for gestational age. Women were categorized according to whether they had an iSUA or a three-vessel cord. The following placental pathologies were compared between the groups using bivariable and multivariable analyses: SGA placenta, maternal vascular malperfusion, high grade fetal vascular malperfusion, and chronic villitis.Results1833 women were included in the analysis: 34 with iSUA and 1799 with three-vessel cord. More than 85% of women in both groups had at least one placental abnormality. After adjusting for nulliparity and neonatal gender, the presence of iSUA was associated with increased odds of high grade fetal vascular malperfusion (adjusted odds ratio 2.8, 95% confidence interval 1.1–7.5) and decreased odds of maternal vascular malperfusion (adjusted odds ratio 0.2, 95% confidence interval 0.1–0.9). There was no significant association with other pathologic findings.ConclusionPathologic placental findings associated with SGA birth differed based on umbilical cord composition. The presence of iSUA in an SGA birth was associated with a higher odds of high grade fetal vascular malperfusion abnormalities and lower odds of maternal vascular malperfusion abnormalities, compared to SGA birth with a 3VC.     

The significance of plasma progesterone levels during early pregnancies achieved after in vitro fertilization (IVF) treatment

Objective Corpus luteum steroidogenesis is lower for in vivo ectopic pregnancy than for intrauterine pregnancy. There is a progesterone hallmark level distinguishing between viable intrauterine pregnancy and nonviable or ectopic pregnancy. This study attempts to answer whether this is also true for in vitro fertilization-treated patients. Study Design Using information retrieved from a computerized database, we compared the plasma 17Β-estradiol (E ₂) and progesterone during the luteal phase and for every 2 to 3 days for several weeks during early pregnancy between those patients with proven ectopic pregnancies and those with singleton and multiple intrauterine pregnancies. Vaginal ultrasonography to detect an intrauterine gestational sac was performed from day 19. A total of 73 pregnancies resulted from the replacement of fresh embryos in our in vitro fertilization-embryo transfer program. Results Only at day 10 post embryo transfer did those patients with ectopic pregnancy show statistically lower mean (SD) serum levels of E ₂ [2257 (SD, 2351) pmol/L] and plasma progesterone [PP; 221 (SD, 283) nmol/L] compared with patients with intrauterine pregnancy, whose mean E₂ was 8846 (SD, 5871) pmol/Land mean PP was 805 (SD, 582) nmol/L (P=0.008). For the rest of the follow-up until surgery was performed in ectopic pregnancy, there were no differences of statistical significance between extrauterine pregnancy and the intrauterine pregnancy groups. Furthermore, only on day 10 post embryo transfer, did we find a discriminatory zone (confidence interval, 95%) for E ₂ levels (903 to 3502 pmol/L for EP vs 6116 to 9493 pmol/L for a singleton and 4875 to 9493 pmol/L for multiple pregnancies). PP levels were 26 to 283 nmol/L for ectopic pregnancy versus 496 to 1096 nmol/L for both singleton and multiple pregnancies. An intrauterine gestational sac was visualized at a mean of 23.2 (SD, 4) days after embryo transfer. On this day, the mean P levels were 982.6 (SD, 286.2) nmol/L for intrauterine and 804.5 (SD, 502.4) nmol/L for ectopic pregnancies (P=NS. Conclusions Except for day 10 post embryo transfer, the steroidogenesis in ectopic pregnancy after in vitro fertilization treatment does not differ from successful intrauterine pregnancy. This observation negates an impaired steroidogenesis for ectopic pregnancy after in vitro fertilization and makes the PP level irrelevant in the diagnosis of pregnancy implantation.     

Placental vessel morphometry in growth retardation and increased resistance of the umbilical artery Doppler flow

OBJECTIVES: To study the tertiary-stem villi vessel lumen and wall thickness of placenta in pregnancy complicated with placental insufficiency and intrauterine growth retardation (IUGR), its correlation with the umbilical artery Doppler flow study, and compare with normal and non-IUGR pregnancies. METHODS: Placentas from 45 deliveries (between 28 and 38 weeks) were collected for morphometric study of the tertiary-stem villi vessels. Each pregnancy had clinical suspicion of IUGR and was confirmed by serial ultrasound biometry, HC/AC ratio, and had abnormal umbilical artery Doppler velocimetry (RI). Each placenta was weighed after trimming of the membrane and the cord. Sections of the placenta (4 micron) were stained with hematoxylin and eosin and periodic acid-Schiff reagents. Tertiary-stem villi vessels were identified under a microscope (x40) and morphometric study was performed. Inner and outer circumferences (2.pi.r) were measured, radii (r) were calculated, and vessel wall thickness was determined (outer r - inner r). These findings were compared with the findings from 78 placentas from normal pregnancies (between 28-40 weeks) and 27 placentas from pregnancies with medical complications without IUGR (non-IUGR) and with normal Doppler velocimetry (between 33 and 38 weeks). RESULTS: Weight of placentas were significantly (P < 0.005) lower in IUGR than the normal and non-IUGR groups. The vessel wall thickness was significantly (P < 0.0001) increased in IUGR group (mean 21.17 +/- 3.16 micron [SD]) compared to normal and non-IUGR groups (mean 13.19 +/- 1.66 micron). With advancing gestational age, the thicknesses of vessel walls in all groups were significantly (P < 0.001) decreased. There was significant (P < 0.001) decrease in lumen circumference in the IUGR group (mean 173 +/- 31 micron) compared to normal and non-IUGR groups (mean 69 +/- 23 micron). Significant (P < 0.001) correlation was observed between the thickness of a vessel wall and the increase in Doppler RI. CONCLUSIONS: Pregnancies with growth retardation are associated with smaller placentas, increase in the thickness of tertiary-stem villi vessel wall, and decrease in lumen circumference. These changes are associated with an increase in the resistance index of the umbilical artery Doppler flow velocimetry.     

Umbilical sP-selectin levels are different in preeclamptic pregnancies with intrauterine normal growth and growth restricted fetus

Objective.?The aim of this study was the analysis of the umbilical cord serum sP-selectin levels in pregnancies complicated by severe preeclampsia with and without intrauterine growth restriction and in normotensive pregnancies.

Patients and methods. The study was carried out on 18 patients with singleton pregnancies complicated by severe preeclampsia with appropriate-for-gestational-age weight infants (group P) and 18 pregnant patients with severe preeclampsia complicated by intrauterine fetal growth restriction (IUGR) (group PI). The control group consisted of 34 patients with singleton uncomplicated pregnancies (group C). Umbilical serum sP-selectin concentrations were estimated using a sandwich ELISA assay according to the manufacturer's instruction (ELISA kit Bender MedSystems Vienna, Austria).

Results.?Our study revealed different concentrations of soluble P-selectin in the umbilical cord in our both studied groups of preeclamptic women with and without IUGR. The umbilical cord levels of sP-selectin were decreased in the group with preeclampsia complicated by IUGR and increased in the preeclamptic women with the normal intrauterine fetal growth. The mean values of umbilical sP-selectin were 839.008?±?625.703?ng/ml in group P, 275.873?±?174.339?ng/ml in group PI, and 288.719?±?199.039?ng/ml in the control group, respectively.

Conclusions.?Higher levels of the umbilical sP-selectin may confirm the presence of platelet and endothelial cell activation and confirm a hypercoagulant state in preeclamptic disorder, especially in preeclampsia without IUGR.     

Hyrtl's anastomosis is normally developed in placentas from small for gestational age infants

BACKGROUND: The aim of this study was to investigate the occurrence and appearance of the anastomosis between the two umbilical arteries in placentas from infants small for gestational age (SGA). METHODS: The arterial systems of 64 placentas from singleton pregnancies resulting in SGA infants were visualized by angiography. The method allowed study of the anastomosis between the umbilical arteries and calculation of the relative placental area supplied by each artery. The results were compared with findings in a previous study of appropriate for gestational age (AGA) infants. One-way analysis of variance (ANOVA) and chi2-analyses were used for statistics. RESULTS: In 56 placentas the anastomosis was represented by a true vessel, in two by a fenestration, and in another two cases by fusion of the umbilical arteries. The anastomosis was absent in one case and another three cases had a single umbilical artery (SUA). When the diameter of the anastomosis was thinner than that of the umbilical arteries, their supply areas were significantly (p < or = 0.001) more symmetrical than in cases with a wider anastomosis. The anatomy of the anastomosis and the relationship between its width and the symmetry between the supply areas of each umbilical artery did not differ in placentas from SGA and AGA infants, despite various types of cord insertion and placentation. CONCLUSION: Static measurements of Hyrtl's anastomosis do not indicate a contributing part for intrauterine growth retardation.     

Placental pathology and pregnancy outcomes in donor and non-donor oocyte in vitro fertilization pregnancies

OBJECTIVE: Intrinsically poor maternal adaptation to pregnancy and dysregulated processes have been postulated to occur as a consequence of an immune response to the feto-placental unit as "foreign" material. The aim of our study was to compare placental pathology and pregnancy outcomes of in vitro fertilization (IVF) pregnancies conceived by donor oocytes with those conceived by non-donor oocytes. STUDY DESIGN: We conducted a retrospective, case-control study on 91 placentas from IVF pregnancies (36 from donor oocytes and 55 from non-donor cycles). All placentas were examined by a single pathologist for signs indicative of an immune response, including chronic villitis, chronic deciduitis, increased perivillous fibrin, ischemic change/infarction, decidual vasculopathy, increased syncytial knots, intervillous thrombi, and retroplacental hematomas. RESULTS: Placentas from donor cycles were significantly more likely to demonstrate certain pathologic findings: chronic villitis (P<0.001), chronic deciduitis (P=0.034), increased perivillous fibrin (P=0.001), ischemic change/ infarction (P=0.001), and intervillous thrombi (P =0.008). There was no statistical significance with respect to decidual vasculopathy, increased syncytial knots, or retroplacental hematomas. CONCLUSION: Pathologic evidence of an immune-mediated process is much more pronounced in donor oocyte IVF pregnancies compared to non-donor cycles. Clinical implications of these findings have yet to be determined.     

Circulating and placental endoglin concentrations in pregnancies complicated by intrauterine growth restriction and preeclampsia

Inadequate trophoblast invasion and spiral artery remodeling leading to poor placental perfusion and hypoxia are believed to underlie preeclampsia (PE) and intrauterine growth restriction (IUGR). Recent studies implicate increased circulating endoglin as a contributor to the pathogenesis of PE. The objective of this study was to determine whether placental and circulating endoglin concentrations are altered in pregnancies complicated by intrauterine growth restricted (IUGR) infants and to address the role of hypoxia on the regulation of placental endoglin. We analyzed 10 placentas each from normal pregnant (NP), PE, and IUGR subjects. Endoglin levels were 2.5-fold higher in preeclamptic placentas compared to NP (15.4+/-2.6 versus 5.7+/-1.0, p<0.01). In contrast, endoglin levels were similar in NP and IUGR placentas (5.7+/-1.0 vs 5.9+/-1.1, p=NS). Placentas from pregnancies with both PE and IUGR exhibited endoglin levels comparable to the PE group and significantly different from normotensive pregnancies with and without IUGR pregnancies (mean 14.9+/-4.0, n=9, p=0.013). Soluble endoglin concentrations in maternal plasma were comparable in NP and IUGR, but higher in women with PE (n=10 per group, p<0.05). Despite a 2-fold increase in hypoxia inducible factor, HIF-1alpha, we did not observe endoglin upregulation in NP, PE, or IUGR placental villous explants exposed to hypoxia (2% oxygen). In contrast to PE, placental or circulating endoglin is not increased in normotensive women delivering small, asymmetrically grown (IUGR) infants at term. The placentas of women with IUGR appear to be fundamentally different from PE women with respect to endoglin, despite the proposed common pathology of deficient trophoblast invasion/spiral artery remodeling and poor placental perfusion.     

Expression of low density lipoprotein receptor messenger ribonucleic acid in placentas from pregnancies with intrauterine growth retardation.

The low density lipoprotein receptor plays an important role in the uptake of maternal plasma lipoproteins for placental steroid metabolism. Using an RNase protection assay, the expression of low density lipoprotein receptor mRNA was measured in human placentas from pregnancies in the second and third trimester and from pregnancies with intrauterine growth retardation. Pregnancies complicated by intrauterine growth retardation showed a significantly higher expression (1.28), compared with the term and preterm pregnancies (P < 0.05). The increased low density lipoprotein receptor expression in placentas from pregnancies with intrauterine growth retardation could be a compensatory mechanism for the lower circulating low density lipoprotein concentrations in women with intrauterine growth retardation.