Sex differences in regional specialisation across the placental surface

There may be regional specialisation in structure and function across the placental surface. In Riyadh, Saudi Arabia, the length and the breadth of the placental surface at birth were highly correlated, but the breadth was more closely associated with the size of the baby. To replicate this we studied 321 pregnant Saudi women in the town of Baish. We measured the size of the newborn babies and their placentas.     

Mother's lifetime nutrition and the size, shape and efficiency of the placenta

Background

Studies have shown that the shape and size of the placenta at birth predict blood pressure in later life. The influences that determine placental morphology are largely unknown. We have examined the role of mother’s body size.

Methods

We studied 522 neonates who were born in a maternity hospital in Mysore, South India. The weight of the placenta and the length and breadth of its surface, were measured after delivery.

Results

Higher maternal fat mass predicted a larger placental surface (p = 0.02), while larger maternal head circumference predicted a more oval placental surface (p = 0.03). Higher maternal fat mass and larger maternal head circumference were associated with greater placental efficiency, indicated by lower ratios of the length (p = 0.0003 and p = 0.0001 respectively) and breadth (p = 0.0002 and p < 0.0001) of the surface to birthweight. In a sub-sample of 51 mothers whose own birthweight was available, higher maternal birthweight was related to lower ratios of the length and breadth of the surface to birthweight (p = 0.01 and 0.002). Maternal height was unrelated to placental size or shape.

Conclusions

Higher maternal fat mass, reflecting the mother’s current nutritional state, and larger maternal head circumference, reflecting the mother’s fetal/infant growth, are associated with changes in the shape and size of the placental surface and greater placental efficiency. We suggest that these associations reflect effects of the mother’s nutrition at different stages of her lifecourse on the development of the placenta and on materno-placento-fetal transfer of nutrients.     

The lifespan of men and the shape of their placental surface at birth

Background

Tall men generally lead longer lives than short men. Within the Helsinki Birth Cohort, however, there is a group of boys among whom being tall when they entered school was associated with reduced lifespan. These boys had birthweights and maternal heights above the median for the cohort; but they tended to be lighter at birth than their mother’s body mass index (weight/height²) in pregnancy predicted. We suggested that, while they had grown rapidly in utero, their growth had faltered at some point; and their tallness at age seven was the result of a resumption during infancy of their rapid growth trajectory. We here examine the size and shape of their placentas at birth to gain further insight into their path of fetal growth.

Methods

We examined all cause mortality in the 1217 men who had birthweights and maternal heights above the median for the cohort. Their birth measurements included placental weight and the length and breadth of the placental surface.

Results

Shorter length of the placental surface was associated with increased mortality (p = 0.002). There was no similar trend with the breadth. Mortality rose as the difference between the length and breadth decreased, that is as the surface became rounder. The hazard ratio was 1.10 (1.03–1.18, p = 0.007) for every cm decrease in the difference. Among men with a round placental surface (length-breadth difference 2 cm or less) increased mortality was associated with lower birthweight (p = 0.03 or 0.005 allowing for mother’s body mass index) and shorter gestation, but not with lower head circumference or length.

Conclusion

Reduced lifespan among men is associated with a particular path of early growth. After rapid growth in early gestation, associated with tall maternal stature, soft tissue growth falters in mid-gestation. Rapid growth resumes in late gestation and continues through infancy.     

Ankyloglossia: a case study in which clipping was not necessary

Following the birth of a baby with a short frenulum, the mother experienced pain from the infant's first feeding that was severe and persistent, despite usually effective interventions. The pain forced the mother to pump her breastmilk and use a feeding bottle and rubber nipple despite her determination to breastfeed. Because the baby's tongue could not extend over the lower gumline, suckling injured all tissue the tongue touched--both the mother's nipples and areolae. Nevertheless, even though this baby's frenulum extended to the tip of the tongue, he was able to adapt his suckling movements to provide good areolar stimulation without persistent nipple damage. Infant growth was not compromised and no surgical intervention was necessary.     

Fetal Growth Restriction is Associated with Accelerated Telomere Shortening and Increased Expression of Cell Senescence Markers in the Placenta

A hallmark of fetal growth restriction (FGR) is restricted placental development and insufficient nutrient supply to the fetus. It has previously been shown that activity levels of telomerase, the enzyme responsible for completing replication of telomeric DNA during cell division, is suppressed in FGR placenta samples as compared to control placenta samples from donors of the same gestational age. Here we examine whether telomere length maintenance is also compromised in FGR placenta samples. Southern analysis of telomere length for placenta and cord blood samples from 32 FGR and 36 control donors, ranging in gestational age from 37 to 40 weeks, revealed significantly shorter telomeres (P ≤ 0.001) in FGR placenta samples, but not cord blood samples. Furthermore, analysis of telomerase extracts, RNA and DNA placental samples from donors with and without idiopathic FGR confirmed a direct association between suppression of telomerase activity and reduced telomere length in FGR placenta. In addition, expression levels of markers of telomere-induced senescence, p21, p16 and EF-1α, were significantly elevated in FGR placenta samples (P ≤ 0.01). These observations support a direct affect of reduced telomerase activity levels on the placental pathology associated with FGR.     

The Role of the Placenta in Fetal Programming—A Review

The fetal origins hypothesis proposes that adult cardiovascular and metabolic disease originate through developmental plasticity and fetal adaptations arising from failure of the materno-placental supply of nutrients to match fetal requirements. The hypothesis is supported by experimental data in animals indicating that maternal nutrition can programme long term effects on the offspring without necessarily affecting size at birth. There is now evidence linking body composition in pregnant women and the balance of nutrient intake during pregnancy with raised levels of cardiovascular risk factors in the offspring. Maternal body composition and diet are thought to affect fetal development and programming as a result of both direct effects on substrate availability to the fetus and indirectly through changes in placental function and structure. Alterations in placental growth and vascular resistance, altered nutrient and hormone metabolism in the placenta, and changes in nutrient transfer and partitioning between mother, placenta and fetus all have important effects on the fetal adaptations thought to be central to programming. Future interventions to improve placental function are likely to have lifelong health benefits for the offspring.     

Placental composition and surface area but not vascularization are altered by maternal protein restriction in the rat

Amino acids are essential nutrients for foetal growth and development, and maternal protein restriction decreases foetal growth despite increasing placental size. To determine if placental structure is altered so as to impair function despite increased size, the effect of maternal protein restriction on the composition and vascularization of the placenta in the rat was determined.Pregnant rats were randomized to receive either a normal protein (20 per cent) or an isocaloric low (8 per cent) protein diet. Placentae were studied at day 18 of gestation. Tissue sections were stained with biotinylated Bandeiraea simplicifolia (BS-1) lectin to allow identification of foetal capillaries, and analysed using stereological techniques.Protein restriction increased total placental volume, but decreased the proportion of the placental volume composed of labyrinth. Consequently the total volumes of labyrinthine tissue and of foetal and maternal blood space were not different between the two groups.Protein restriction increased the surface area density and total surface area of the materno-foetal interface, but did not alter foetal capillary surface area, diameter or length.This study found that maternal protein restriction is associated with an increase in placental size, and that this enlargement is accompanied by increases in some, but not all, structural correlates of function.     

Morphometric studies on villi in human term placentae and the effects of altitude, ethnic grouping and sex of newborn

Stereological methods were used to test whether or not altitudinal, ethnic and sex differences in birthweight in Bolivia are associated with differences in placental morphology. Estimates of the volumes, surface areas, lengths and diameters of villi and of fetal capillaries were obtained by analysing paraffin sections of tissue. The average highland placenta contains villi of smaller overall volume, surface area and length. These villi possess a less voluminous fetal vascular space, and the capillaries are smaller in mean diameter. The average Amerindian placenta has longer but thinner capillaries than the average placenta delivered by non-indigenous women. Altitude and ethnic grouping interact to have an effect on total villous length, whilst ethnic grouping and sex interact to influence fetal capillary length. These structural differences are discussed in the context of their likely impact on placental functioning, notably on exchange by passive diffusion.     

Submucosal leiomyoma of the uterus incorporated into the fetal membranes and mimicking a placental neoplasm: a case report

Leiomyoma of the placenta is uncommon. We present a leiomyoma of the fetal membranes that was incidentally discovered on examination of a spontaneously expulsed placenta following Caesarean section. Although it is an uncommon entity, it is known that leiomyomas may arise from the vasculature nourishing the fetal membranes. The baby was male and genetic studies were performed to detect Y chromosome in tumoral tissue. Polymerase chain reaction technique demonstrated Y chromosome in placental tissue but not in tumour tissue. Thus the tumour was finally diagnosed as incorporated benign uterine leiomyoma.     

The sex-specific effects of famine on the association between placental size and later hypertension

Background

People who had low birth weight are at increased risk of hypertension. This may reflect fetal programming by undernutrition. Placental size is also associated with hypertension. Maternal undernutrition during the Dutch famine reduced placental surface area. We examined whether maternal undernutrition altered the relationship between placental size and later hypertension.

Methods

Retrospective cohort study among 860 subjects born in Amsterdam during 1943-47. 216 subjects were taking anti-hypertensive medication. Birth records included placental length and breadth from which we calculated its area.

Results

Among men who were not in utero during the famine hypertension was associated with a small placental surface area due to a small placental breadth, and with an oval-shaped surface. The OR for hypertension was 0.83 (95% CI 0.70 to 1.00) for a 40 cm² increase in surface area. Among men who were in utero during the famine hypertension was associated with a large placental surface area due to a large placental breadth, and with a round-shaped surface. The OR for hypertension was 1.34 (95% CI 0.99 to 1.80) for a 40 cm² increase in surface area. The associations between placental size and hypertension in men who were and were not in utero during the famine were significantly different (p values for interaction = 0.008 for placental surface area, 0.001 for the breadth and 0.01 for the difference in the two diameters). Among women hypertension was not associated with placental size.

Conclusions

Our study provides the first direct evidence that changes in maternal diet during pregnancy alter the relationship between placental size and later hypertension among men but not women. We suggest that among men who were not in utero during the famine, hypertension was related to impaired implantation, whereas among men who were in utero during the famine it was related to compensatory expansion of the placental surface.     

前置胎盘附着位置与剖宫产子宫切口选择

在剖宫产术前可通过病史资料和影像学检查来了解前置胎盘附着位置,而剖宫产术中直视所见虽是最终诊断,但却是滞后的诊断,故其只能作为对术前评估不足的补充。剖宫产术是前置胎盘终止妊娠的主要方式,而选择子宫切口沿着胎盘边缘相比必须打洞穿过胎盘组织取胎者的母源性失血和新生儿贫血发生率显著降低。对不同前置胎盘的患者的术式选择应个别对待,根据超声胎盘定位及术中评估等制定个体化手术方案,只要选对子宫的切口,尽量避免胎盘开窗,可有效减少母儿不良预后。     

Effects of famine on placental size and efficiency

Background

Placental growth responds to maternal influences including diet. We have examined placental size, shape and efficiency among babies born around the time of the 5-month wartime famine in Holland 1944-1945.

Methods

We examined the birth records of 2414 term singleton babies born in Amsterdam during 1943-1947. The records included the size of the baby and the thickness of the placental surface, together with its length and breadth which we used to calculate its area and volume.

Results

Compared to babies born before the famine babies who were in utero during the famine had smaller placental areas. Babies whose mothers conceived after the famine ended also had smaller placental areas. Famine was associated with a 19 cm² decrease in area. Babies who were in mid-late gestation during the famine were 160 g lighter than would have been predicted from their placental area (p < 0.001). Babies who were in early gestation during the famine, or who were conceived after it had ended were 102 g heavier than would have been predicted from their placental area (p < 0.001). These latter babies were either longer or had larger head circumferences depending on when the mother experienced the famine. Among babies who were in early gestation during the famine the reduction in placental area was greater in boys than girls (p for interaction 0.03).

Conclusion

Famine impaired the normal processes of placentation, even among babies who were conceived after it had ended. In babies who were in mid-late gestation during the famine, the placenta was less efficient. In babies who were in early gestation during the famine, or who were conceived after it had ended, the placenta was more efficient. The placentas of boys and girls responded differently to famine.     

Circulating levels of maternal plasma cell-free pregnancy-associated placenta-specific microRNAs are associated with placental weight

The aim of this study was to investigate the relationship between plasma concentration of cell-free pregnancy-associated placenta-specific microRNAs and clinical variables (placental weight, maternal body mass index, and neonatal birth weight). Circulating levels of cell-free pregnancy-associated placenta-specific microRNAs (miR-515-3p, miR-517a, miR-517c and miR-518b) in maternal plasma were measured by quantitative real-time RT-PCR in sixty-two pregnant women. The levels of cell-free pregnancy-associated placenta-specific microRNAs were significantly associated with placental weight, but not associated with body mass index or birth weight. Therefore, the measurement of cell-free pregnancy-associated placenta-specific miRNAs levels in maternal plasma may reflect the pregnancy status related to placenta volume.     

Mothers of very low birthweight babies: who supports them?

Delivery of a very low birthweight (VLBW) baby usually precipitates a crisis in the lives of a family, and the mother's adequacy and competence are challenged. To whom does she turn for support? Twenty-one mothers of singleton VLBW babies were interviewed on six occasions from 1 week after the birth to 3 months after the baby's discharge from hospital. At each interview they were asked whom they had found most supportive. Whilst partners were generally supportive, other relatives seemed to have difficulty knowing how to help. There was a rallying to the mother's aid during the initial crisis period after the birth and again immediately after the baby's discharge home but few sustained this effort during the chronic stages when the mother was tired, depressed and anxious. Though hospital staff were considered supportive for the most part, there were areas for improvement in their ability to listen empathically to the mother's own perceptions of events and behaviours which were at great variance to their own. Health visitors appeared to have real difficulties. They demonstrated a marked lack of knowledge and understanding and they were considered very unsupportive by many mothers.     

The impact of pregnancy weight and glucose on the metabolic health of mother and child in the south west of the UK

OBJECTIVE: to explore relationships between maternal pre-pregnancy weight, third trimester glucose, baby birth weight, weight and metabolic health of the mother and child 5 years after birth. DESIGN: an observational study set within a non-intervention, longitudinal cohort study looking at insulin resistance in children. SETTING: a teaching hospital in the south west of the United Kingdom. PARTICIPANTS: 300 mothers and their five-year-old children from randomly selected Plymouth schools, stratified according to socioeconomic status. MEASUREMENTS: were obtained from obstetric records maternal pre-pregnant weight, random and fasting third trimester blood glucose, baby birth weight. Five years later the following measurements were made of the mother and child: height, weight, glucose and insulin resistance. FINDINGS: five years after the pregnancy, 33% of the mothers were overweight, with an additional 19% obese. In the children 13% of boys were overweight (4% obese), and in the girls, 26% were overweight (5% obese). In the five-year-old children, weight (r=0.28, p<0.001) but not birth weight (r=0.03, p=0.573), correlated with insulin resistance. Maternal pre-pregnant weight was related to both random and fasting third trimester glucose, and to insulin resistance 5 years later. Third trimester fasting glucose, even within a normal range, was a better predictor than random glucose of the baby's birth weight (r=0.39, p=0.044) and the mother's future insulin resistance (r=0.67, p<0.001). No maternal measures predicted insulin resistance in the child at 5 years. CONCLUSIONS: maternal weight had an important influence on the gestational environment, and predicted insulin resistance 5 years later. Fasting glucose, even within the reference range, was a better predictor than random glucose of the baby's birth weight and the mother's future insulin resistance. IMPLICATIONS FOR PRACTICE: these concern the importance of pre-conception weight management, and support replacement of routine random glucose sampling during the third trimester with an earlier, fasting measurement.     

Metabolism of vitamin D3 in the placental tissue of normal and preeclampsia complicated pregnancies and premature births

The aim of this study was to analyze the hormonal basis for low 1,25(OH)2D3 circulating levels in patients with preeclampsia and/or preterm deliveries. The activity and expression of the 1 alphaOHase, 25-OHase, 24-OHase and VDR in the placental tissue of normal pregnancies, preeclampsia-complicated pregnancies and premature births were investigated. The mRNA of the enzymes was detected in the placental tissue from preeclamptic pregnancies and compared to those of normal placental tissue. Real time PCR analysis showed a significant increased 1 alpha-OHase gene expression in preeclamptic patients, and the gene expression of 24-OHase was significantly decreased. With regard to the 25-OHase the median value of the normal placental tissue was significantly higher than in the placental tissue of preeclamptic patients. The real time analysis of all target genes also showed significant differences in normal placental tissue compared to placental tissue from premature births (VDR: p = 0.041; 1 alpha-OHase: p = 0.013; 24-OHase: p = 0.007; 25-OHase p = 0.027). Our observation of reduced VDR expression on mRNA level in placental tissue indicates a possible dependence of the modulation of VDR expression from proliferation and differentiation processes. It can be speculated whether the down-regulation of VDR in the examined placenta cells was the result of an altered production of calcitriol by these cells. We found a significantly higher 1 alpha-OHase-expression in the placental tissue of pregnant women with preeclampsia or preterm birth compared to healthy pregnant women, whereas the expression of 25-OHase was significantly reduced. These results correlate with other studies and support the significance of the placenta regarding metabolism malfunctions as they were observed in the calcium metabolism for preeclampsia. That a placenta with preeclampsia expresses less 1 alpha-OHase-mRNA and shows less 1 alpha-OHase-activity than in placental samples of inconspicuous placentae, can be granted as a specific alteration in the placental ability to synthesize adequate amounts of 1,25(OH)2D3.     

Ethanol and the placenta: A review.

OBJECTIVE: In this paper we review published studies of alcohol exposure on placentation, placenta growth and function. METHODS: We searched PubMed using the MeSH terms: placenta, ethanol, fetal alcohol syndrome and prenatal exposure with delayed effects. We searched the years 1996-2006 and used the references from other articles to expand our search. We limited the search to English only and human only. We excluded studies using choriocarcinoma and animal studies. We grouped the 66 papers into seven topic areas for ease of review. RESULTS: Alcohol exposure is associated with placental dysfunction, decreased placental size, impaired blood flow and nutrient transport, endocrine changes, increased rates of stillbirth and abruption, umbilical cord vasoconstriction, and low birth weight. CONCLUSIONS: Prenatal alcohol exposure has a broad range of adverse effects on placental development and function. Additional research on placental development from populations with heavy alcohol exposure should be encouraged. A tissue bank of placentas with detailed assessment of exposure to alcohol, smoking and other relevant data should be considered as a repository to support additional research.     

Placental size at 19 weeks predicts offspring bone mass at birth: findings from the Southampton Women's Survey

ObjectivesIn this study we investigate the relationships between placental size and neonatal bone mass and body composition, in a population-based cohort.Study design914 mother–neonate pairs were included. Placental dimensions were measured via ultrasound at 19 weeks gestation. Dual X-ray absorptiometry (DXA) was performed on the neonates within the first two weeks of life.ResultsWe observed positive relationships between placental volume at 19 weeks, and neonatal bone area (BA; r = 0.26, p < 0.001), bone mineral content (BMC; r = 0.25, p < 0.001) and bone mineral density (BMD; r = 0.10, p = 0.001). Thus placental volume accounted for 6.25% and 1.2% of the variation in neonatal BMC and BMD respectively at birth. These associations remained after adjustment for maternal factors previously shown to be associated with neonatal bone mineral accrual (maternal height, smoking, walking speed in late pregnancy, serum 25(OH) vitamin D and triceps skinfold thickness).ConclusionsWe found that placental volume at 19 weeks gestation was positively associated with neonatal bone size and mineral content. These relationships appeared independent of those maternal factors known to be associated with neonatal bone mass, consistent with notion that such maternal influences might act through modulation of aspects of placental function, e.g. utero-placental blood flow or maternal nutrient concentrations, rather than placental size itself. Low placental volume early in pregnancy may be a marker of a reduced postnatal skeletal size and increased risk of later fracture.     

Placenta chorioangioma. Case report at Hospital Español

Placenta chorioangioma is the most frequent non-trophoblastic tumor of the placenta. Its real incidence is unknown. This incidence is reported as 1% in microscopically examined placentas and counts with clinical evidence in approximately 1: 3,500 to 9,000 births. This tumor is not generally associated to maternal fetal complications, unless the tumor size surpasses a diameter of 5 cm or is near the place of umbilical cord insertion. When the tumor is big, it can complicate the pregnancy with hydramnios, postpartum bleeding, delay in the intrauterine growth, or congestive heart failure in the newborn. The clinic case belongs to a Korean female patient, aged 32, without important antecedents. A placental tumouration, 50.2 x 44.1 mm, was detected by ultrasound to this patient in her 37 1/7 week of pregnancy. She has a normoevolutive pregnancy whose was a term, she had an a eutocic delivery, getting a male whose weight was 2,850 g. The baby is still alive. The placenta histopathological study reported placental chorioangioma, which infracted partially, with multifocal calcification areas.