Placental weight centiles adjusted for age, parity and fetal sex

The First Fetal Case of Shwachman-Diamond Syndrome Mimicking Vascular Growth Restriction

Shwachman-Diamond Syndrome (SDS) is a rare autosomal recessive genetic condition with 90% of cases associated with biallelic pathogenic variants in the Shwachman-Bodian-Diamond Syndrome (SBDS) gene on chromosome 7q.11.21. SDS belongs to ribosomopathies since SBDS gene encodes a protein involved in ribosomal maturation. Its phenotypic postnatal hallmark features include growth delay, bone marrow failure, exocrine pancreatic insufficiency, and skeletal abnormalities. We report a first fetal case of Shwachman-Diamond syndrome and extend its phenotype before birth. The clinical features mimicked vascular growth restriction with FGR and shortened long bones, associated with abnormal Doppler indices. Non-restricted fetal autopsy after termination of pregnancy allowed deep phenotyping disclosing the features of fetal skeletal dysplasia. Post-fetopathological trio exome sequencing identified biallelic pathogenic variants in the SBDS gene. Genotype-phenotype correlations confirmed the diagnosis and enabled an adequate genetic counseling of the parents. Our case is another example of the positive impact of fetal autopsy coupled with post-fetopathological genomic studies, even in the cases that were hitherto classified as maternal or fetal vascular malperfusion.

Placental ACE2 Expression: A Possible Pathogenetic Mechanism for Infantile Hemangiomas

ACE2 is a mono-carboxypeptidase with remarkable vasculo-protective properties, and its expression in the human placenta plays a central role in blood pressure homeostasis and fetal perfusion. Therefore, an alteration in the placental expression of ACE2 could be responsible for reduced placental perfusion and infantile hemangioma (IH) development. Study placentae were collected from patients affected by IHs who were referred to our Dermatology Clinic from 2016 to 2022, while control placentae were randomly collected while matching cases for gestational age. Immunohistochemical investigations were performed with a recombinant anti-ACE2 rabbit monoclonal antibody. A total of 47 placentae were examined, including 20 study placentae and 27 control ones. The mean placental weight was significantly lower in the study group (380.6 g vs. 502.3 g; p = 0.005), while subclinical chorioamnionitis occurred more frequently in the study group (20% vs. 0%, p = 0.03). The mean ACE2 expression was dramatically lower in the study group (χ2 = 42.1 p < 0.001), and the mean placental weight was significantly lower when ACE2 was not expressed compared to the 25-75% and >75% classes of expression (p < 0.05). This study demonstrated that ACE2, as a marker for tissue hypoxia, is dramatically hypo-expressed in placentae belonging to mothers who delivered one or more babies with IH compared to the controls.

The smaller firstborn: exploring the association of parity and fetal growth

PURPOSE

To investigate the association of parity with a range of neonatal anthropometric measurements in a cohort of uncomplicated term singleton pregnancies.

METHODS

Retrospective cohort study of patients with a singleton term birth at a single tertiary center (2014-2020) was carried out. The primary exposure was parity. The following neonatal anthropometric measures were considered: birthweight, head circumference, length, ponderal index, and neonatal body mass index (BMI).

RESULTS

A total of 8134 patients met the study criteria, 1949 (24.0%) of whom were nulliparous. Compared with multiparous patients, infants of nulliparous patients had a lower mean percentile for birthweight (43.1 ± 26.4 vs. 48.3 ± 26.8 percentile, p < 0.001), head circumference (44.3 ± 26.4 vs. 48.1 ± 25.5 percentile, p < 0.001), length (52.6 ± 25.1 vs. 55.5 ± 24.6 percentile, p < 0.001), ponderal index (34.4 ± 24.0 vs. 37.6 ± 24.2 percentile, p < 0.001), and BMI (39.1 ± 27.1 vs. 43.9 ± 27.3 percentile, p < 0.001). In addition, infants of nulliparous patients had higher odds of having a small (< 10th percentile for gestational age) birthweight (aOR 1.32 [95% CI 1.12-1.56]), head circumference (aOR 1.54 [95% CI 1.29-1.84]), length (aOR 1.50 [95% CI 1.16-1.94]), ponderal index (aOR 1.30 [95% CI 1.12-1.51]), and body mass index (aOR 1.42 [95% CI 1.22-1.65]). Most neonatal anthropometric measures increased with parity until a parity of 2, where it seemed to reach a plateau.

CONCLUSION

Parity has an independent impact on a wide range of neonatal anthropometric measures, suggesting that parity is associated with both fetal skeletal growth and body composition. In addition, the association of parity with fetal growth does not follow a continuous relationship but instead reaches a plateau after the second pregnancy.

Impact of birth weight to placental weight ratio and other perinatal risk factors on left ventricular dimensions in newborns: a prospective cohort analysis

OBJECTIVES

To investigate the association between birth weight to placental weight (BW/PW) ratio, and echocardiographic left ventricle (LV) morphology at birth, while accounting for other relevant perinatal factors.

METHODS

A prospective cohort study was conducted on neonates at NewYork-Presbyterian Brooklyn Methodist Hospital from 2014 to 2018, categorized by their BW/PW percentile. Missing data were imputed with principal component analysis. Chi-squared and one-way analysis of variance were used to compare BW/PW groups and the best regression model was selected using a genetic and backward stepwise algorithm.

RESULTS

We analyzed 827 neonates in three BW/PW groups: small (n=16), normal (n=488), and large (n=323). Placental thickness and smallest diameter were positively correlated with several LV parameters, including inter-ventricular septal thickness during diastole (IVSd) (p=0.002, p<0.001) and systole (IVSs) (p=0.001, p<0.001), LV posterior wall thickness at end of diastole (LVPWd) (p=0.003, p<0.001) and systole (LVPWs) (p<0.001, p<0.001), LV mass (p=0.017, p<0.001), and LV mass/volume (p=0.011, p<0.001). The BW/PW ratio correlated with an increased shortening fraction (estimate=0.29, 95 % CI 0.03-0.55, p=0.027). PW correlated with IVSs (p=0.019), while the longest placental diameter was linked to a decrease in LV internal dimension during diastole (LVIDd) (estimate=-0.07, p=0.039), LV mass (estimate=-0.11, p=0.024), and LV mass/volume (estimate=-0.55, p=0.005).

CONCLUSIONS

This study found that several placental factors, including the BW/PW ratio, can independently affect LV dimension and morphology, highlighting the importance of fetal growth and placental health in the physiological adaptation of the fetal heart. More research is needed to establish causation and inform newborn prevention strategies.

Sociodemographic factor associations with maternal and placental outcomes: A cluster and partial least squares regression analysis

INTRODUCTION

Maternal social disadvantage adversely affects maternal and offspring health, with limited research on placental outcomes. Therefore, we examined maternal sociodemographic factor associations with placental and birth outcomes in general (Lifeways Cross-Generation Cohort) and at-risk (PEARS Study of mothers with overweight or obesity) populations of pregnant women.

METHODS

TwoStep cluster analysis profiled Lifeways mothers (n = 250) based on their age, parity, marital status, household income, private healthcare insurance, homeowner status, and education. Differences in placental and birth outcomes (untrimmed placental weight (PW), birthweight (BW) and BW:PW ratio) between clusters were assessed using one-way ANOVA and chi-square tests. Partial least squares regression analysed individual effects of sociodemographic factors on placental and birth outcomes in Lifeways and PEARS mothers (n = 461).

RESULTS

Clusters were classified as "Married Homeowners" (n = 140, 56 %), "Highest Income" (n = 58, 23.2 %) and "Renters" (n = 52, 20.8 %) in the Lifeways Cohort. Renters were younger, more likely to smoke, have a means-tested medical card and more pro-inflammatory diets compared to other clusters (p < 0.01). Compared to Married Homeowners, renters' offspring had lower BW (-259.26 g, p < 0.01), shorter birth length (-1.31 cm, p < 0.01) and smaller head circumference (-0.59 cm, p = 0.02). PLS regression analyses identified nulliparity as having the greatest negative effect on PW (Lifeways and PEARS) while being a homeowner had the greatest positive effect on PW (Lifeways).

CONCLUSION

Certain combinations of sociodemographic factors (particularly homeownership) were associated with less favourable lifestyle factors, and with birth, but not placental outcomes. When explored individually, parity contributed to the prediction of placental and birth outcomes in both cohorts of pregnant women.

Placental weight percentile curves in a Danish population

INTRODUCTION

The role of the placenta is to transport oxygen and nutrients to the fetus, and a well-functioning placenta is vital to fetal health. Our aim was to develop placental weight percentile curves adjusted by gestational age, and stratified by major maternal comorbidities.

MATERIAL AND METHODS

The study was a population study in a Danish cohort. Data was drawn from The Medical Birth Register and the National Patient Register. We included singleton births with a gestational age of 22 + 0 to 42 + 6 weeks. We excluded multiple pregnancies, stillbirths and retained placentas. A total of 611 418 placentas were included. Percentile line graphs were created in groups of all placentas, hypertensive disorders and diabetic disorders.

RESULTS

Tables and figures are presented for placental weight percentile curves according to gestational age for all placentas, hypertensive disorders and diabetic disorders, respectively. Placental weight was generally higher in the diabetic placentas, and lower in the hypertensive placentas.

CONCLUSIONS

These percentile curves may serve as a reference for other populations, and may be useful for other studies investigating the role of the placenta in relation to pregnancy outcomes, and health in later life.

Maternal dietary patterns and placental outcomes among pregnant women in Los Angeles

INTRODUCTION

Epidemiological studies have linked prenatal maternal diet to fetal growth, but whether diet affects placental outcomes is poorly understood.

METHODS

We collected past month dietary intake from 148 women in mid-pregnancy enrolled at University of California Los Angeles (UCLA) antenatal clinics from 2016 to 2019. We employed the food frequency Diet History Questionnaire II and generated the Healthy Eating Index-2015 (HEI-2015), the Alternate Healthy Eating Index for Pregnancy (AHEI-P), and the Alternate Mediterranean Diet (aMED). We conducted T2-weighted magnetic resonance imaging (MRI) in mid-pregnancy (1st during 14-17 and 2nd during 19-24 gestational weeks) to evaluate placental volume (cm3) and we measured placenta weight (g) at delivery. We estimated change and 95 % confidence interval (CI) in placental volume and associations of placenta weight with all dietary index scores and diet items using linear regression models.

RESULTS

Placental volume in mid-pregnancy was associated with an 18.9 cm3 (95 % CI 5.1, 32.8) increase per 100 gestational days in women with a higher HEI-2015 (≥median), with stronger results for placentas of male fetuses. We estimated positive associations between placental volume at the 1st and 2nd MRI and higher intake of vegetables, high-fat fish, dairy, and dietary intake of B vitamins. A higher aMED (≥median) score was associated with a 40.5 g (95 % CI 8.5, 72.5) increase in placenta weight at delivery, which was mainly related to protein intake.

DISCUSSION

Placental growth represented by volume in mid-pregnancy and weight at birth is influenced by the quality and content of the maternal diet.

Placental size at gestational week 36: Comparisons between ongoing pregnancies and deliveries

INTRODUCTION

We aimed to compare placental size and placental size relative to fetal size (ratio) in ongoing pregnancies examined by magnetic resonance imaging (MRI) at gestational week 36 with placental size among all deliveries at gestational week 36 during the same time period.

MATERIAL AND METHODS

Ongoing unselected singleton pregnancies (n = 89) were examined by MRI at median gestational week 36+5 days during 2017-2018, and placental and fetal volumes (cm3 ) were calculated. The placental size and ratio in ongoing pregnancies were compared with placental size and ratio among all deliveries in Norway at gestational week 36 (median gestational week 36+4 days) during 2016-2019 (n = 5582). For comparison of size, we converted volume (cm3 ) in ongoing pregnancies into grams as: cm3  × 1.05 (density of placental and fetal tissue).

RESULTS

In ongoing pregnancies, median placental size was 873  (interquartile range [IQR] 265) grams and median size of all delivered placentas was 613 (IQR 290) grams. Placental size was smaller among the delivered placentas independent of delivery mode: 760 (IQR 387) grams among elective cesarean deliveries (n = 465) and 590 (IQR 189) grams among vaginal deliveries after spontaneous onset of labor (n = 2478). Median ratio in ongoing pregnancies was higher than among deliveries: 0.31 (IQR 0.08) vs 0.21 (IQR 0.08). The ratio was higher in ongoing pregnancies independent of delivery mode: 0.24 (IQR 0.17) among elective cesarean deliveries vs 0.21 (IQR 0.05) among vaginal deliveries after spontaneous onset of labor.

CONCLUSIONS

The placenta is larger in ongoing pregnancies than among deliveries. This finding suggests that placental size decreases during labor and delivery, possibly by transfer of blood to the fetus. Our finding also suggests that reference values of placental size based on delivered placentas are not valid for ongoing pregnancies.

Inter-pregnancy interval and placental weight. A population based follow-up study in Norway

INTRODUCTION

We studied changes in placental weight from the first to the second delivery according to length of the inter-pregnancy interval.

METHODS

We followed all women in Norway from their first to their second successive singleton pregnancy during the years 1999-2019, a total of 271 184 women. We used data from the Medical Birth Registry of Norway and studied changes in placental weight (in grams (g)) according to the length of the inter-pregnancy. Adjustments were made for year and maternal age at first delivery, changes in the prevalence of maternal diseases (hypertension and diabetes), and a new father to the second pregnancy.

RESULTS

Mean placental weight increased from 655 g at the first delivery to 680 g at the second. The adjusted increase in placental weight was highest at inter-pregnancy intervals <6 months; 38.2 g (95 % CI 33.0g-43.4 g) versus 23.2 g (95 % CI 18.8g-27.7 g) at inter-pregnancy interval 6-17 months. At inter-pregnancy intervals ≥18 months, placental weight remained higher than at the first delivery, but was non-different from inter-pregnancy intervals 6-17 months. Also, after additional adjustment for daily smoking and body mass index in sub-samples, we found the highest increase in placental weight at the shortest inter-pregnancy interval. We estimated no difference in gestational age at delivery or placental to birthweight ratio according to inter-pregnancy interval.

DISCUSSION

Placental weight increased from the first to the second pregnancy, and the increase was most pronounced at short inter-pregnancy intervals. The biological causes and implications of such findings remain to be studied.

Genome-wide association study of placental weight identifies distinct and shared genetic influences between placental and fetal growth

A well-functioning placenta is essential for fetal and maternal health throughout pregnancy. Using placental weight as a proxy for placental growth, we report genome-wide association analyses in the fetal (n = 65,405), maternal (n = 61,228) and paternal (n = 52,392) genomes, yielding 40 independent association signals. Twenty-six signals are classified as fetal, four maternal and three fetal and maternal. A maternal parent-of-origin effect is seen near KCNQ1. Genetic correlation and colocalization analyses reveal overlap with birth weight genetics, but 12 loci are classified as predominantly or only affecting placental weight, with connections to placental development and morphology, and transport of antibodies and amino acids. Mendelian randomization analyses indicate that fetal genetically mediated higher placental weight is causally associated with preeclampsia risk and shorter gestational duration. Moreover, these analyses support the role of fetal insulin in regulating placental weight, providing a key link between fetal and placental growth.

Does maternal vitamin D status influence placental weight or vascular and inflammatory pathology? Secondary analysis from the Kellogg Pregnancy Study

INTRODUCTION

Positive effects of vitamin D (vitD) supplementation on comorbidities of pregnancy (COP) have been explored; however, few studies have elucidated the pathophysiology behind the development of these COP and the potential relationship with derangements in placental development and morphology. Additionally, it is known that placentas weighing 10th-90th % for gestational age are associated with better outcomes. Therefore, the objective of this study was to assess the impact of resulting circulating serum 25(OH)D concentrations associated with intake of high or low doses of supplementary vitD on placental development and morphology in women who participated in a randomized double blind, placebo-controlled trial of vitD supplementation. We hypothesized that if maternal serum 25(OH)D concentration (vitD status marker) is insufficient/deficient, then placental weight and % for gestational age (GA) will be smaller and will correlate with increased vascular and inflammatory placental pathologic findings.

METHODS

The findings of the present study are a secondary analysis of data generated from a previously reported randomized controlled trial (RCT), the Kellogg Vitamin D Pregnancy Study. Pregnant women (n = 297) in this RCT (January 2013 - April 2018) were randomly assigned to 400 IU vs. 4400 IU vitD/day (10-14 weeks' gestational age) and followed to delivery. 132 placentas were analyzed by pathologists blinded to treatment, and the 2016 Amsterdam Consensus Criteria were used to categorize grouping/grading of placental pathology and weight. Total [25(OH)D] was measured using radioimmunoassay (ng/mL). Chi-square and Student's t-test were used to show the difference in maternal characteristics by treatment group and by placental weight. Chi-square analysis was used to determine differences between the percent pathology findings by treatment group. Students t-test was used to determine the differences in vitD status and the frequency of placental lesions. Association between [25(OH)D] area under the curve (AUC) and placental morphology were determined in a regression model that included maternal BMI ≥ 30 kg/m2, race/ethnicity, and vitD treatment group allocation. Data were analyzed using SAS v9.4 (Cary, NC) and statistical significance was indicated by p < 0.05.

RESULTS

The percent pathology findings by treatment group were not significantly different for each of the placental pathology categories as defined by the 2016 Amsterdam Consensus Criteria including placental weight. However, when using 25(OH)D as a biomarker for vitD status, linear regression model showed maternal serum [25(OH)D] AUC was significantly associated with greater placental weight (p = 0.023). Logistic regression models showed mothers with BMI ≥ 30 kg/m2 had larger placental weight (p = 0.046), and Hispanic and white/Caucasian mothers had greater placental weights than Black American mothers (p = 0.025). When placentas ≥ 90th % for GA, n = 7, were removed from the placental pool, Pearson correlation still showed a positive association between maternal serum 25(OH)D AUC and placental weight (p = 0.011). In a second linear regression model of placentas ≥ 90th % for GA (n = 7) vs. placentas < 90th % (n = 108), maternal serum 25(OH)D AUC was significantly greater in those placentas ≥ 90th % (p = 0.03); however, this was not associated with increased perinatal mortality. CONCLUSION FINDINGS: suggest increasing maternal serum [25(OH)D] via vitamin D supplementation during pregnancy did not adversely affect placental morphology; trends showed those in the treatment group had fewer placental lesions. Placental weight was found to be significantly associated with [25(OH)D] AUC, which represents maternal vitamin D status over the course of pregnancy; 7 placentas ≥ 90th % for GA were not associated with perinatal mortality.

Altitude Modifies the Effect of Parity on Birth Weight/Length Ratio: A Study Comprising 2,057,702 Newborns between 1984 and 2020 in Austria

(1) Background: Lower birth weight among newborns in higher altitudes has been well documented in previous literature. Several possible causes for this phenomenon have been investigated, including biophysiological adaptation, epigenetic or genetic mechanisms or lifestyle changes. This is the first study to show the effect modification of altitude and parity on the birth weight length ratio (BWLR) in women resident in moderate altitudes compared to a low sea level.; (2) Methods: This population-based study obtained data on altitude (0-300, 300-500, 500-700,700-900, >900 m), parity (1, 2, …, 7, 8/9), birth weight and length on all births in Austria between 1984 and 2020 from birth certificates provided by Statistics Austria. The BWLR was calculated, and the effect of moderate altitude and parity was estimated using multivariable linear mixed models adjusting for predefined variables. Sub-group regression analyses were conducted by altitude group. (3) Results: Data on 2,057,702 newborns from 1,280,272 mothers were analyzed. The effect of parity on BWLR, as indicated by the difference of BWLR between the first- and second-born infants, ranged between 1.87 to 2.09 g per centimeter across all altitude groups. Our analyses found that the effect of parity on BWLR diminished from parity three onwards at altitude 0-300, whilst the effect of parity on BWLR continued to increase at higher than 300 m and was most notable in the highest altitude group >900 m. (4) Conclusions: Findings from our study indicated that the negative effect of increasing altitude on BWLR was deprived for newborns of higher parity. It shows that the residential altitude can modify the effect of parity on BWLR.

Relationship between Birth Order and Postnatal Growth until 4 Years of Age: The Japan Environment and Children’s Study

Later-borns tend to be shorter than first-borns in childhood and adulthood. However, large-scale prospective studies examining growth during infancy according to birth order are limited. We aimed to investigate the relationship between birth order and growth during the first 4 years of life in a Japanese prospective birth cohort study. A total of 26,249 full-term singleton births were targeted. General linear and multivariable logistic regression models were performed and adjusted for birth weight, parents’ heights, maternal age at delivery, gestational weight gain, maternal smoking and alcohol drinking status during pregnancy, household income, breastfeeding status, and Study Areas. The multivariate adjusted mean length Z-scores in “first-borns having no sibling”, “first-borns having siblings”, “second-borns”, and “third-borns or more” were −0.026, −0.013, 0.136, and 0.120 at birth and −0.324, −0.330, −0.466, and −0.569 at 10 months, respectively. Results similar to those at 10 months were observed at 1.5, 3, and 4 years. The adjusted odds ratios (95% confidence intervals) of short stature at 4 years in “first-borns having siblings”, “second-borns”, and “third-borns or more” were 1.08 (0.84–1.39), 1.36 (1.13–1.62), and 1.50 (1.20–1.88), respectively, versus “first-borns having no sibling”. Birth order was significantly associated with postnatal growth and may be a factor predisposing to short stature in early childhood.

Associations between maternal dietary scores during early pregnancy with placental outcomes

Background and aims

Individual macronutrient and micronutrient effects on placental growth have been widely investigated. However, the influence of overall maternal diet is relatively unknown. Therefore, the aim of this study is to examine associations between a range of maternal dietary scores during early pregnancy with placental outcomes, and to investigate whether there is evidence of sexual dimorphism.

Methods

This analysis of the Lifeways Cross-Generational Cohort includes 276 mother-child pairs. A validated 148-item semi-quantitative food frequency questionnaire assessed maternal diet in early pregnancy. Dietary scores reflecting dietary quality [Healthy Eating Index (HEI-2015), Dietary Approaches to Stop Hypertension (DASH)], dietary inflammatory potential [Dietary Inflammatory Index (DII) and the energy adjusted DII (E-DII)], dietary antioxidant status [Dietary Antioxidant Quality (DAQ)], and glycemic and insulinemic loads/indices (GL/GI, IL/II) were calculated. Linear regression analyses assessed maternal dietary score relationships with untrimmed placental weight (PW) and birth weight:placental weight (BW:PW) ratio.

Results

In fully adjusted models, maternal E-DII and GI were positively associated, and HEI-2015 and DAQ were negatively associated with PW (B: 12.31, 95% CI: 0.41, 24.20, p = 0.04, B: 4.13, 95% CI: 0.10, 8.17, p = 0.04, B: -2.70, 95% CI: -5.03, -0.35, p = 0.02 and B: -15.03, 95% CI: -28.08, -1.98, p = 0.02, for E-DII, GI, HEI-2015 and DAQ respectively). Maternal DAQ associations with BW:PW ratio were attenuated. When stratified by sex, maternal GI and pregnancy-specific DAQ were associated with PW in female offspring (B: 5.61, 95% CI: 0.27, 10.96, p = 0.04 and B: -15.31, 95% CI: -30.35, -0.27, p = 0.046). Maternal E-DII and HEI-2015 were associated with PW in males (B: 24.31, 95% CI: 5.66, 42.96, p = 0.01 and B: -3.85, 95% CI: -7.47, -0.35, p = 0.03 respectively).

Conclusion

The results of this novel investigation suggest that maternal diet may influence placental development. Female fetuses may be more sensitive to increased glucose levels whereas male fetuses may be more susceptible to in-utero stresses that are regulated by inflammatory pathways and overall diet quality. Hence, early pregnancy offers an opportune time for a mother to prioritize dietary changes that focus on reducing inflammatory and glycemic responses.

Association of placental and umbilical cord characteristics with cerebral palsy: national cohort study

OBJECTIVES

Cerebral palsy (CP) is a group of movement disorders usually diagnosed in childhood. A substantial proportion are thought to be caused by antenatal events. Abnormalities of the umbilical cord and placenta are associated with an increased risk of adverse neonatal outcomes, but it is unclear whether these conditions also carry an increased risk of CP. We aimed to determine whether abnormalities of the umbilical cord or placenta are associated with CP and assess if these associations differ by sex of the child or gestational age at birth.

METHODS

We performed a national cohort study by linking data from The Medical Birth Registry of Norway with other national registries. All liveborn singletons born between 1999 and 2017 (n = 1 087 486) were included and followed up until the end of 2019. Diagnoses of CP were provided by the Norwegian National Insurance Scheme and the Norwegian Patient Register. We used generalized estimating equations and multilevel log binomial regression to calculate relative risks (RR), adjusted for year of birth, and stratified analyses were carried out based on sex and gestational age at birth. Exposures were abnormal umbilical cord (velamentous or marginal insertion, single umbilical artery (SUA), knots and entanglement), and placental abnormalities (retained placenta, placental abruption and previa).

RESULTS

A total of 2443 cases with CP (59.8% males) were identified. Velamentous cord insertion (adjusted RR (aRR), 2.11 (95% CI, 1.65-2.60)), cord knots (aRR, 1.53 (95% CI, 1.15-2.04)) and placental abnormalities (placenta previa (aRR, 3.03 (95% CI, 2.00-4.61)), placental abruption (aRR, 10.63 (95% CI, 8.57-13.18)) and retained placenta (aRR, 1.71 (95% CI, 1.32-2.22))) carried an increased risk of CP. Velamentous cord insertion was associated with CP regardless of gestational age or sex. A retained placenta was associated with a 2-fold increased risk for CP in males, while the associations of SUA and cord knot with CP were significant only among females.

CONCLUSIONS

The detection of placental and umbilical cord abnormalities may help identify children at increased risk of CP. The associations between placental or umbilical cord abnormalities and the risk of CP do not vary substantially with gestational age at birth or sex of the child. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Case report: A novel de novo IGF2 missense variant in a Finnish patient with Silver-Russell syndrome

Silver-Russell syndrome (SRS, OMIM 180860) is a rare imprinting disorder characterized by intrauterine and postnatal growth restriction, feeding difficulties in early childhood, characteristic facial features, and body asymmetry. The molecular cause most commonly relates to hypomethylation of the imprinted 11p15.5 IGF2/H19 domain but remains unknown in about 40% of the patients. Recently, heterozygous paternally inherited pathogenic variants in IGF2, the gene encoding insulin-like growth factor 2 (IGF2), have been identified in patients with SRS. We report a novel de novo missense variant in IGF2 (c.122T > G, p.Leu41Arg) on the paternally derived allele in a 16-year-old boy with a clinical diagnosis of SRS. The missense variant was identified by targeted exome sequencing and predicted pathogenic by multiple in silico tools. It affects a highly conserved residue on a domain that is important for binding of other molecules. Our finding expands the spectrum of disease-causing variants in IGF2. Targeted exome sequencing is a useful diagnostic tool in patients with negative results of common diagnostic tests for SRS.