Preliminary report: immunoperoxidase-linked human placental lactogen as a histopathologic index of perinatal morbidity and mortality

Anatomic study of placental dysfunction may benefit from the applications of new routine techniques. Immunohistochemical staining for human placental lactogen (HPL) was used in 3 cases illustrating different perinatal disorders. The amount of HPL labeling ranged from high in an acute anoxic death due to abruptio placentae, through decreased in a case of maternal hypertension, to low in severe intrauterine growth retardation. Such information complements standard clinical and pathologic studies. Ten percent buffered Formalin was superior to Bouin's fixative and alcoholic Formalin for the demonstration of HPL. Even after 4 days of refrigeration at 4 degrees C, all of the syncytiotrophoblastic tissue was labeled in sections of paraffin-embedded, Formalin-fixed normal placentas.     

Placental Protein Distribution in Maternal Diabetes Mellitus: An Immunocytochemical Study

Placentas associated with maternal diabetes are generally characterized by features of villous immaturity. We correlated the villous histology with the immunocytochemical distribution of four trophoblastic proteins: beta human chorionic gonadotropin (beta HCG), placental alkaline phosphatase (PLAP), pregnancy specific beta-1-glycoprotein (SP1), and human placental lactogen (HPL) in 14 third-trimester placentas associated with diabetes mellitus. Staining was increased for beta HCG and decreased for PLAP, SP1, and HPL in the diabetic placentas compared to control placentas of similar gestational age. This pattern was most prominent in areas of marked architectural villous immaturity within individual placentas and suggests concomitant functional immaturity.     

Placental protein distribution in maternal diabetes mellitus: an immunocytochemical study

Placentas associated with maternal diabetes are generally characterized by features of villous immaturity. We correlated the villous histology with the immunocytochemical distribution of four trophoblastic proteins: beta human chorionic gonadotropin (beta HCG), placental alkaline phosphatase (PLAP), pregnancy specific beta-1-glycoprotein (SP1), and human placental lactogen (HPL) in 14 third-trimester placentas associated with diabetes mellitus. Staining was increased for beta HCG and decreased for PLAP, SP1, and HPL in the diabetic placentas compared to control placentas of similar gestational age. This pattern was most prominent in areas of marked architectural villous immaturity within individual placentas and suggests concomitant functional immaturity.     

Quantitative structure of the normal human placenta from 10 weeks of gestation to term

Ninety five placentae from normal term and 'normal' preterm pregnancies have been analysed by morphometry. The growth of the whole placenta, of the microscopic placental constituents and of the villous surface area has been measured in placentae from uncomplicated pregnancies from 10 weeks of gestation to term to provide data for comparison with values from placentae from pathological pregnancies. No evidence for placental senescence is found in the placentae from normal pregnancies up to term although the rate of growth of the villous surface area decreases gradually from approximately 34 weeks gestation. Evidence is given to suggest that in normal pregnancy villi continue to elaborate until term. The relationship of villous surface area to fetal growth is assessed.     

Placental size of small-for-gestational-age infants at term

Placental size was compared between appropriate-for-gestational age (AGA) and small-for-gestational age (SGA) infants born at term. Placental weight, chorionic plate area and villous surface area were significantly reduced in the SGA infants. Although the ratio of placental weight to birth weight was similar in the AGA and SGA infants, the latter had significantly underweight placentas for their head circumference and crown-heel length. The ratios of placental weight to assessed brain weight and villous surface area to assessed brain weight were also significantly reduced in the SGA infants. It is concluded that the study SGA infants had both absolutely and relatively small placentas.     

Infant size and relative placental weight at birth

In 811 unselected term infants, the ratios of placental weight to (a) body weight, (b) head circumference and (c) body length were assessed as possible determinants of infant size at birth. Unlike the placentofetal weight ratio, the ratio of placental weight to either head circumference or body length proved an excellent predictor of infant size, ponderal index and skinfold thickness. Infants with a relatively small placenta at term were growth-retarded when compared to infants with relatively large placentas.It is suggested that the ratio of placental weight to either head circumference or body length at term reflects not only relative placental size but also the functional capacity of the placenta to meet the nutritional demands of the fetus.     

Chronic Villitis of Unknown Etiology in Twin Gestations

Chronic villitis of unknown etiology (CVUE) is a frequently encountered placental lesion associated with poor pregnancy outcome. We examined 22 twin placentas with CVUE to determine its distribution and clinicopathological significance in twin gestations. CVUE affected both twins' placental portions with an approximately equal degree of severity in 12 of 22 cases (9 dichorionic, 3 monochorionic). Only one twin's placental portion was affected in 8 cases (8 dichorionic). In the remaining 2 (1 dichorionic, 1 monochorionic), both placental portions were affected, but the CVUE was significantly more severe in one. The CVUE varied in extent from rare foci to diffuse involvement. Seven of the 22 (32%) pairs of twins had intrapair weight differences of15% or greater, and 14 pairs were premature. The twins with placental involvement by CVUE had a lower mean birthweight than their cotwins with less or no CVUE; however, these results were not statistically significant. CVUE may affect placentas from one or both twins, and may be a cause of discordant twin size.     

THE TRANSCAPILLARY ESCAPE RATE OF T-1824 IN HEALTHY NEWBORN INFANTS The Influence of the Placental Transfusion

The transcapillary escape rate of T-1824 was measured in 12 normal newborn infants and found to be significantly higher among infants with late clamping of the umbilical cord (25.0% per hour) than in early-clamped infants (19.1% per hour). The magnitude of the placental transfusion was assessed from the volume of the residual placental blood and it was demonstrated that the transcapillary escape rate of T-1824 increases parallel to the placental transfusion. The disappearance rate of the early-clamped infants was almost the same as that previously found in early-clamped infants of diabetic mothers.     

Early embryonic losses in mice induced by diethylstilbestrol

Estrogens cause embryonic lethality and the disturbance of early placental development in mice. Diethylstilbestrol (DES) at 1, 10, or 100 µg/kg was orally administered to Institute of Cancer Research mice on gestational days (GD) 4 through 8, and the uterus and placenta were examined histopathologically on GD 9. Decidua of DES‐treated mice showed insufficient development, and the uterine lumen at the implantation site did not effectively minimize. The trophoblast giant cell layer was not separated from the uterine lumen by the decidua capsularis, and hemorrhage from the denuded trophoblast giant cell layer into the uterine lumen was noted at the peripheral part of the decidua basalis. The results of the present study suggest that decidual hypoplasia and subsequent placental hemorrhage causes fetal death due to the administration of DES during the early stage of pregnancy.     

Two Live-Born Infants with Trisomy 22

The autopsy findings and karyotypes of two live-born fetuses with full trisomy 22 are discussed. Confined placental mosaicism was documented in one of the two cases. Confined placental mosaicism may play a role in the intrauterine survival of some trisomy 22 conceptions.     

The duration of maternal cigarette smoking, fetal and placental disorders

Data from a large prospective study of pregnancy were used to determine whether the number of years a mother had smoked cigarettes influenced the development of common fetal and placental disorders. Three disorders increased in frequency when mothers had smoked for more than 6 yr: placenta previa +143%, abruptio placentae +72% and large placental infarcts +37% (all P less than 0.05). Mothers' current smoking habits had a smaller influence on the frequency of these disorders, and the effects of smoking were largely independent of maternal pregnancy weight gain. The placentas of smokers had microscopic evidences of underperfusion from the uterus. The placental abnormalities were influenced by both the number of years mothers had smoked and by their current smoking habits.     

Placental transfer of IgG subclasses in a Japanese population

BACKGROUND: Maternal immunoglobulin G (IgG), transferred across the placenta to the fetus during intrauterine life, is an important component of the neonatal immunological defence mechanisms against infection. There is controversy with respect to differences in placental transfer of the different IgG subclasses, and no definite data are available on a Japanese population. Therefore, we investigated placental transfer of IgG subclasses in a Japanese population. METHODS: A total of 228 matched pairs of cord and maternal serum samples (20-42 weeks gestation) were assayed for each IgG subclass by an enzyme-linked immunosorbent assay. RESULTS: The mean values and hierarchy of cord/maternal concentration ratios of IgG subclasses at 40 weeks gestation were as follows: IgG1(1.47) > IgG3(1.17) = IgG4(1.15) > IgG2(0.80). The cord/maternal concentration ratios of all IgG subclasses were positively correlated to gestational age. The mean ratios for IgG1 and IgG4 nearly reached a plateau at 39 and 37 weeks gestation, respectively, while those for IgG2 and IgG3 increased until 41 weeks gestation. The ratios of all IgG subclasses for full-term deliveries were reciprocally correlated to the respective maternal IgG subclass serum levels. CONCLUSIONS: The results suggest that although all four IgG subclasses are actively transferred across the placenta, the efficiency of their transfer ranks in the order IgG1 > IgG3 = IgG4 > IgG2. The different results as to placental transfer of IgG subclasses in the literature might be due, at least in part, to different maternal IgG subclass serum levels in the populations studied.     

Variation in size at birth in infants born small for gestational age in Lithuania

The aim of this study was to describe the heterogeneity in body proportions of infants born small for gestational age (SGA), defined by birthweight, and to study the relationship of placental size with neonatal anthropometric measurements. Anthropometry was evaluated in 107 symmetrically and asymmetrically growth-retarded infants born SGA (birthweight <-2 SD) and compared with 181 appropriate-for-gestational age infants (AGA; birthweight and length +/- 2 SD). Study children were born at Kaunas University Hospital during the period from 1 January 1998 to 25 August 2000. Two-thirds of SGA children were light (SGA(W)) and one-third was both light and short (SGA(WL)) for gestational age. Infants in both SGA groups were significantly leaner than AGA children. SGA(WL) infants had significantly larger heads in relation to their length compared with SGA(W) and even AGA children, probably indicating a brain-sparing effect. SGA(WL) children had the lowest mean placental weight, but the highest placental weight to birthweight (PW/BW) ratio. The PW/BW ratio was inversely correlated with most infant measurements; the strongest negative relationship was observed with birthlength and lower leg length. CONCLUSION: There is heterogeneity in children born SGA, defined by birthweight. It is suggested that the two SGA groups represent the continuum of intrauterine growth retardation, with an initial reduction in trophic growth and a subsequent retardation of linear growth. The PW/BW ratio is a strong indicator for impaired prenatal linear growth.     

IgG deficiency in association with placental oedema

Deficiency of the immunoglobulin G (IgG) in the human newborn is rare in the absence of maternal hypogammaglobulinaemia. Low concentrations of IgG in cord blood were found in 3 conditions — the donor twin in the feto-fetal transfusion syndrome, hydrops fetalis and congenital hepatic disease. These were all associated with placental oedema. It is suggested that the oedema may be responsible for a disturbance in maternofetal placental transfer.     

PERINATAL ACIDOSIS AND PLACENTAL TRANSFUSION1

Umbilical artery pH and residual placental blood volume (RPBV) were determined for 75 full-term newborn infants born by vaginal delivery. For 39 infants of multiparous mothers (IMM), there was a significant relationship between fetal acidosis and reduced RPBV. For 36 infants of primiparous mothers (IPM) a significant relationship was not present. Results of an earlier study suggested that perinatal acidosis was associated with reduced RPBV. The present study confirms this association for IMM's. The reason for the lack of a clearcut effect in IPMs is unknown.     

Placental tyrosine transport and maternal phenylketonuria

Brush border and basal plasma membrane vesicles prepared from normal human placental syncytiotrophoblast have been used to study L-tyrosine transport across placenta in an attempt to investigate the aetiology of the fetal damage found in maternal phenylketonuria. The results suggest that competition for transport with a grossly raised L-phenylalanine concentration at the basal surface of the trophoblast is responsible for the suppressed delivery of L-tyrosine to the fetus across the placenta.     

Hepatic Hemangioendotheliomas, Placental Chorioangiomas, and Dysmorphic Kidneys in Beckwith-Wiedemann Syndrome

A 4-month-old female, birth weight 3150 g, had a history of maternal eclampsia, multiple placental chorioangiomas, and persistent neonatal hypoglycemia. Macroglossia and enlarged kidneys were recorded. Autopsy revealed multiple hepatic hemangioendotheliomas (type 1), massive cardiomegaly, and bilateral nephromegaly. Both kidneys were lobulated with active glomerulogenesis and clusters of immature tubules and foci of dysplastic medullary ducts. The features suggest that the nephrogenesis was secondary to the persistence of actively branching nephron-inducing ducts. Nodular hyperplasia of the adrenal cortex (adrenoblastomatosis) was present. This report expands the list of tumors to be found in Beckwith-Wiedemann syndrome (BWS).     

Confined Placental Mosaicism and Stillbirth

The cause of stillbirth can usually be determined in only 20% of cases. An increased frequency of adverse pregnancy outcome, including pregnancy loss, intrauterine growth restriction, and premature labor, has been observed in association with confined placental mosaicism (CPM), which is characterized by a discrepancy between the karyotype of the fetus and placenta. Specific chromosomal trisomies have been observed in CPM more frequently than others, with trisomy of chromosomes 7, 16, and 18 being the most prevalent. In pregnancies with CPM it has been shown that the zygote is often trisomic, and postzygotic loss of the additional chromosome occurred in the embryonic progenitor cells leading to a dichotomy between the placenta and the embryo/fetus. In one third of such cases fetal uniparental disomy (UPD), which is the presence of both homologues of a chromosome derived from one parent, can be expected. The specific role of the trisomic placenta and the presence of fetal UPD in cases of altered intrauterine fetal development has not been fully established for various chromosomes. Therefore, to enhance our understanding of the pathogenesis of stillbirth it is imperative that cytogenetic analysis of both fetal and placental tissues be performed in all cases of unexplained stillbirth.     

The influence of some perinatal variables on neonatal blood pressure

Adult hypertension has been linked to fetal growth. This study investigates whether this link is evident in the newborn. We measured blood pressure by oscillometry in 248 healthy neonates on day 3/4 of life. Antenatal data and neonatal measurements were obtained from hospital records. Elevated neonatal blood pressure correlated with higher birthweight. There was no correlation between placental weight and blood pressure. Babies born by caesarean section had lower systolic blood pressure. Babies of maternal smokers had higher diastolic blood pressure, but their mothers (45% of this study) had lower blood pressure than non-smokers. Thus, smoking was associated with a significant change in both maternal and neonatal blood pressure, and may be an important influence on the developing cardiovascular system.