Scholarly Works - Obstetrics and Gynaecology


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  • ItemPublished versionOpen Access
    ELABELA/APELA Levels Are Not Decreased in the Maternal Circulation or Placenta among Women with Preeclampsia.
    (Elsevier BV, 2018-08) Pritchard, Natasha; Kaitu'u-Lino, Tu'uhevaha J; Gong, Sungsam; Dopierala, Justyna; Smith, Gordon CS; Charnock-Jones, D Stephen; Tong, Stephen; Gong, Sung [0000-0001-5796-4423]; Smith, Gordon [0000-0003-2124-0997]; Charnock-Jones, Stephen [0000-0002-2936-4890]
    The genetic deletion of apelin receptor early endogenous ligand (Elabela; official name APELA) produces a preeclampsia-like phenotype in mice. However, evidence linking ELABELA with human disease is lacking. Therefore, we measured placental mRNA and circulating ELABELA in human samples. ELABELA mRNA (measured by RNA sequencing) was unchanged in 82 preeclamptic placentas compared with 82 matched controls (mean difference, 0.53%; 95% CI, -25.9 to 27.0; P = 0.78). We measured circulating ELABELA in 32 women with preterm preeclampsia (delivered at <34 weeks' gestation) and 32 matched controls sampled at the same gestational age. There was no difference in circulating ELABELA concentrations in the preeclamptic cohort compared with controls (median, 28.5 pg/mL; 95% CI, 5.3 to 63.2 versus median, 20.5 pg/mL; 95% CI, 9.2 to 58.0, respectively); the median difference was 8.0 pg/mL (95% CI, -17.7 to 12.1; P = 0.43). In contrast, soluble FLT1 (a protein with an established association with preeclampsia) mRNA was increased in placental tissue (mean difference, 34.9%; 95% CI, 16.6 to 53.1; P = 0.001), and circulating concentrations were 16.8-fold higher among the preeclamptic cohort (P < 0.0001). In conclusion, we were able to recapitulate the association between circulating soluble FLT1 and preeclampsia, but there was no association with ELABELA. The speculated clinical relevance of observations in the murine model linking ELABELA to preeclampsia likely are incorrect.
  • ItemAccepted versionOpen Access
    Screening for fetal growth restriction using ultrasound and the sFLT1/PlGF ratio in nulliparous women: a prospective cohort study
    (Elsevier, 2018-08) Smith, GCS; Gaccioli, Francesca; Sovio, Ulla; Cook, Emma; Hund, Martin; Charnock-Jones, D Stephen; Smith, Gordon [0000-0003-2124-0997]; Gaccioli, Francesca [0000-0001-7178-8921]; Sovio, Ulla [0000-0002-0799-1105]; Charnock-Jones, Stephen [0000-0002-2936-4890]
    ABSTRACT Background Fetal growth restriction is a major determinant of perinatal morbidity and mortality. The condition has no gold standard definition but a widely used proxy is delivery of a small for gestational age (SGA) infant (<10th percentile) combined with an adverse pregnancy outcome. Effective screening for FGR is an area of unmet clinical need. We sought to determine the diagnostic effectiveness of the combination of ultrasonic fetal biometry and measurement of the ratio of soluble fms-like tyrosine kinase receptor 1 (sFLT1) to placenta growth factor (sFLT1:PlGF) in predicting adverse pregnancy outcome associated with delivery of an SGA infant. Methods We recruited 4,512 nulliparous women to a prospective cohort study which involved serial antenatal blood sampling and blinded ultrasound scans. We determined the association between the combination of an elevated sFLT1:PlGF ratio (>85th percentile) and ultrasonically suspected SGA (<10th percentile) at both 28 and 36 weeks of gestational age (wkGA). The outcome following the 28wkGA measurement was preterm delivery of an SGA infant. The outcome following the 36wkGA measurement was subsequent delivery of an SGA infant associated with maternal preeclampsia or perinatal morbidity or mortality. All definitions of exposure and outcome were predefined prior to conducting the analysis. Findings At 28wkGA, 47/3981 (1·2%) women had the combination of ultrasonic SGA and an elevated sFLT1:PlGF ratio: the positive likelihood ratio for preterm delivery of an SGA infant associated with this combination was 41·1 (95% CI 23·0-73·6), the sensitivity was 38·5% and the specificity was 99·1%. At 36wkGA, 102/3747 (2·7%) women had the combination of ultrasonic SGA and an elevated sFLT1:PlGF ratio: the positive likelihood ratio for delivery of an SGA infant associated with maternal preeclampsia or perinatal morbidity or mortality was 17·5 (95% CI 11·8-25·9), the sensitivity was 37·9% and the specificity was 97·8%. The positive likelihood ratios at both gestational ages were much higher than previously described definitions of suspected fetal growth restriction employing purely ultrasonic assessment. Interpretation The combination of ultrasonically suspected SGA plus an elevated sFLT1:PlGF ratio in unselected nulliparous women identifies a relatively small proportion of women who have high absolute risks of clinically important adverse outcomes. Screening and intervention based on this approach is likely to result in net benefit and this would be an appropriate subject for a randomised controlled trial. Funding NIHR Cambridge Comprehensive Biomedical Research Centre, Medical Research Council, and Stillbirth and neonatal death society (Sands).
  • ItemPublished versionOpen Access
    Correcting for optimistic prediction in small data sets.
    (Oxford University Press (OUP), 2014-08-01) Smith, Gordon CS; Seaman, Shaun R; Wood, Angela M; Royston, Patrick; White, Ian R; Smith, Gordon [0000-0003-2124-0997]; Seaman, Shaun [0000-0003-3726-5937]; Wood, Angela [0000-0002-7937-304X]
    The C statistic is a commonly reported measure of screening test performance. Optimistic estimation of the C statistic is a frequent problem because of overfitting of statistical models in small data sets, and methods exist to correct for this issue. However, many studies do not use such methods, and those that do correct for optimism use diverse methods, some of which are known to be biased. We used clinical data sets (United Kingdom Down syndrome screening data from Glasgow (1991-2003), Edinburgh (1999-2003), and Cambridge (1990-2006), as well as Scottish national pregnancy discharge data (2004-2007)) to evaluate different approaches to adjustment for optimism. We found that sample splitting, cross-validation without replication, and leave-1-out cross-validation produced optimism-adjusted estimates of the C statistic that were biased and/or associated with greater absolute error than other available methods. Cross-validation with replication, bootstrapping, and a new method (leave-pair-out cross-validation) all generated unbiased optimism-adjusted estimates of the C statistic and had similar absolute errors in the clinical data set. Larger simulation studies confirmed that all 3 methods performed similarly with 10 or more events per variable, or when the C statistic was 0.9 or greater. However, with lower events per variable or lower C statistics, bootstrapping tended to be optimistic but with lower absolute and mean squared errors than both methods of cross-validation.
  • ItemAccepted versionOpen Access
    Universal screening for foetal growth restriction.
    (Elsevier BV, 2018-05) Smith, Gordon CS; Smith, Gordon [0000-0003-2124-0997]
    Foetal growth restriction (FGR) is a major cause of morbidity and mortality. Clinical methods for identifying women whose pregnancies are affected by FGR do not perform well. Despite this, the current approach to screening includes the clinical assessment of risk and targeted use of ultrasound. Universal screening of women using ultrasound has not been shown to improve outcomes in randomised controlled trials and, when implemented nationally in France, appeared mostly to change outcomes for the worse through the effect of iatrogenic prematurity on false positives. Research is currently focused on the development of screening tests with higher sensitivity and specificity, for example, by combining ultrasound with placental biomarkers. The diagnostic tests employed should be identified through high-quality research that investigates the diagnostic accuracy of the tests, and this will usually involve blinding of the results. Therefore, future trials of screening and intervention will require careful planning. Moreover, if trials are to be powered for perinatal death, large sample sizes will be required.
  • ItemAccepted versionOpen Access
    Making stillbirths visible: a systematic review of globally reported causes of stillbirth.
    (Wiley, 2018-01) Reinebrant, HE; Leisher, SH; Coory, M; Henry, S; Wojcieszek, AM; Gardener, G; Lourie, R; Ellwood, D; Teoh, Z; Allanson, E; Blencowe, H; Draper, ES; Erwich, JJ; Frøen, JF; Gardosi, J; Gold, K; Gordijn, S; Gordon, A; Heazell, Aep; Khong, TY; Korteweg, F; Lawn, JE; McClure, EM; Oats, J; Pattinson, R; Pettersson, K; Siassakos, D; Silver, RM; Smith, Gcs; Tunçalp, Ö; Flenady, V; Smith, Gordon [0000-0003-2124-0997]
    BACKGROUND: Stillbirth is a global health problem. The World Health Organization (WHO) application of the International Classification of Diseases for perinatal mortality (ICD-PM) aims to improve data on stillbirth to enable prevention. OBJECTIVES: To identify globally reported causes of stillbirth, classification systems, and alignment with the ICD-PM. SEARCH STRATEGY: We searched CINAHL, EMBASE, Medline, Global Health, and Pubmed from 2009 to 2016. SELECTION CRITERIA: Reports of stillbirth causes in unselective cohorts. DATA COLLECTION AND ANALYSIS: Pooled estimates of causes were derived for country representative reports. Systems and causes were assessed for alignment with the ICD-PM. Data are presented by income setting (low, middle, and high income countries; LIC, MIC, HIC). MAIN RESULTS: Eighty-five reports from 50 countries (489 089 stillbirths) were included. The most frequent categories were Unexplained, Antepartum haemorrhage, and Other (all settings); Infection and Hypoxic peripartum (LIC), and Placental (MIC, HIC). Overall report quality was low. Only one classification system fully aligned with ICD-PM. All stillbirth causes mapped to ICD-PM. In a subset from HIC, mapping obscured major causes. CONCLUSIONS: There is a paucity of quality information on causes of stillbirth globally. Improving investigation of stillbirths and standardisation of audit and classification is urgently needed and should be achievable in all well-resourced settings. Implementation of the WHO Perinatal Mortality Audit and Review guide is needed, particularly across high burden settings. FUNDING: HR, SH, SHL, and AW were supported by an NHMRC-CRE grant (APP1116640). VF was funded by an NHMRC-CDF (APP1123611). TWEETABLE ABSTRACT: Urgent need to improve data on causes of stillbirths across all settings to meet global targets. PLAIN LANGUAGE SUMMARY: Background and methods Nearly three million babies are stillborn every year. These deaths have deep and long-lasting effects on parents, healthcare providers, and the society. One of the major challenges to preventing stillbirths is the lack of information about why they happen. In this study, we collected reports on the causes of stillbirth from high-, middle-, and low-income countries to: (1) Understand the causes of stillbirth, and (2) Understand how to improve reporting of stillbirths. Findings We found 85 reports from 50 different countries. The information available from the reports was inconsistent and often of poor quality, so it was hard to get a clear picture about what are the causes of stillbirth across the world. Many different definitions of stillbirth were used. There was also wide variation in what investigations of the mother and baby were undertaken to identify the cause of stillbirth. Stillbirths in all income settings (low-, middle-, and high-income countries) were most frequently reported as Unexplained, Other, and Haemorrhage (bleeding). Unexplained and Other are not helpful in understanding why a baby was stillborn. In low-income countries, stillbirths were often attributed to Infection and Complications during labour and birth. In middle- and high-income countries, stillbirths were often reported as Placental complications. Limitations We may have missed some reports as searches were carried out in English only. The available reports were of poor quality. Implications Many countries, particularly those where the majority of stillbirths occur, do not report any information about these deaths. Where there are reports, the quality is often poor. It is important to improve the investigation and reporting of stillbirth using a standardised system so that policy makers and healthcare workers can develop effective stillbirth prevention programs. All stillbirths should be investigated and reported in line with the World Health Organization standards.
  • ItemAccepted versionOpen Access
    Age at menarche and the risk of operative delivery.
    (Informa UK Limited, 2019-02) Chong, Hsu Phern; Frøen, J Frederik; Richardson, Sylvia; Liquet, Benoit; Charnock-Jones, D Stephen; Smith, Gordon CS; Richardson, Sylvia [0000-0003-1998-492X]; Charnock-Jones, Stephen [0000-0002-2936-4890]; Smith, Gordon [0000-0003-2124-0997]
    OBJECTIVES: We sought to evaluate the impact of later menarche on the risk of operative delivery. POPULATION: We studied 38,069 eligible women (first labors at term with a singleton infant in a cephalic presentation) from the Norwegian Mothers and Child Cohort Study. The main exposures were the age at menarche and the duration of the interval between menarche and the first birth. METHODS: Poisson's regression with a robust variance estimator. MAIN OUTCOME MEASURES: Operative delivery, defined as emergency cesarean or assisted vaginal delivery (ventouse extraction or forceps). RESULTS: A 5 year increase in age at menarche was associated with a reduced risk of operative delivery (risk ratio [RR] 0.84, 95%CI 0.78, 0.89; p < .001). Adjustment for the age at first birth slightly strengthened the association (RR 0.79, 95%CI 0.74, 0.84; p < .001). However, the association was lost following adjustment for the menarche to birth interval (RR 0.99, 95%CI 0.93, 1.06; p = .81). A 5 years increase in menarche to birth interval was associated with an increased risk of operative delivery (RR 1.26, 95%CI 1.23, 1.28; p < .001). This was not materially affected by adjustment for an extensive series of maternal characteristics (RR 1.23, 95%CI 1.20, 1.25; p < .001). CONCLUSIONS: Later menarche reduces the risk of an operative first birth through shortening the menarche to birth interval. This observation is consistent with the hypothesis that the pattern and/or duration of prepregnancy exposure of the uterus to estrogen and progesterone contributes to uterine aging.
  • ItemAccepted versionOpen Access
    Docosahexaenoic Acid Supplementation in Pregnancy Modulates Placental Cellular Signaling and Nutrient Transport Capacity in Obese Women.
    (The Endocrine Society, 2017-12-01) Lager, Susanne; Ramirez, Vanessa I; Acosta, Ometeotl; Meireles, Christiane; Miller, Evelyn; Gaccioli, Francesca; Rosario, Fredrick J; Gelfond, Jonathan AL; Hakala, Kevin; Weintraub, Susan T; Krummel, Debra A; Powell, Theresa L; Gaccioli, Francesca [0000-0001-7178-8921]
    CONTEXT: Maternal obesity in pregnancy has profound impacts on maternal metabolism and promotes placental nutrient transport, which may contribute to fetal overgrowth in these pregnancies. The fatty acid docosahexaenoic acid (DHA) has bioactive properties that may improve outcomes in obese pregnant women by modulating placental function. OBJECTIVE: To determine the effects of DHA supplementation in obese pregnant women on maternal metabolism and placental function. DESIGN: Pregnant women were supplemented with DHA or placebo. Maternal fasting blood was collected at 26 and 36 weeks' gestation, and placentas were collected at term. SETTING: Academic health care institution. SUBJECTS: Thirty-eight pregnant women with pregravid body mass index ≥30 kg/m2. INTERVENTION: DHA (800 mg, algal oil) or placebo (corn/soy oil) daily from 26 weeks to term. MAIN OUTCOMES: DHA content of maternal erythrocyte and placental membranes, maternal fasting blood glucose, cytokines, metabolic hormones, and circulating lipids were determined. Insulin, mTOR, and inflammatory signaling were assessed in placental homogenates, and nutrient transport capacity was determined in isolated syncytiotrophoblast plasma membranes. RESULTS: DHA supplementation increased erythrocyte (P < 0.0001) and placental membrane DHA levels (P < 0.0001) but did not influence maternal inflammatory status, insulin sensitivity, or lipids. DHA supplementation decreased placental inflammation, amino acid transporter expression, and activity (P < 0.01) and increased placental protein expression of fatty acid transporting protein 4 (P < 0.05). CONCLUSIONS: Maternal DHA supplementation in pregnancy decreases placental inflammation and differentially modulates placental nutrient transport capacity and may mitigate adverse effects of maternal obesity on placental function.
  • ItemAccepted versionOpen Access
    Screening for fetal growth restriction using fetal biometry combined with maternal biomarkers.
    (Elsevier BV, 2018-02) Gaccioli, Francesca; Aye, Irving LMH; Sovio, Ulla; Charnock-Jones, D Stephen; Smith, Gordon CS; Gaccioli, Francesca [0000-0001-7178-8921]; Aye, Irving [0000-0003-3400-5005]; Sovio, Ulla [0000-0002-0799-1105]; Charnock-Jones, Stephen [0000-0002-2936-4890]; Smith, Gordon [0000-0003-2124-0997]
    Fetal growth restriction is a major determinant of perinatal morbidity and mortality. Screening for fetal growth restriction is a key element of prenatal care but it is recognized to be problematic. Screening using clinical risk assessment and targeting ultrasound to high-risk women is the standard of care in the United States and United Kingdom, but the approach is known to have low sensitivity. Systematic reviews of randomized controlled trials do not demonstrate any benefit from universal ultrasound screening for fetal growth restriction in the third trimester, but the evidence base is not strong. Implementation of universal ultrasound screening in low-risk women in France failed to reduce the risk of complications among small-for-gestational-age infants but did appear to cause iatrogenic harm to false positives. One strategy to making progress is to improve screening by developing more sensitive and specific tests with the key goal of differentiating between healthy small fetuses and those that are small through fetal growth restriction. As abnormal placentation is thought to be the major cause of fetal growth restriction, one approach is to combine fetal biometry with an indicator of placental dysfunction. In the past, these indicators were generally ultrasonic measurements, such as Doppler flow velocimetry of the uteroplacental circulation. However, another promising approach is to combine ultrasonic suspicion of small-for-gestational-age infant with a blood test indicating placental dysfunction. Thus far, much of the research on maternal serum biomarkers for fetal growth restriction has involved the secondary analysis of tests performed for other indications, such as fetal aneuploidies. An exemplar of this is pregnancy-associated plasma protein A. This blood test is performed primarily to assess the risk of Down syndrome, but women with low first-trimester levels are now serially scanned in later pregnancy due to associations with placental causes of stillbirth, including fetal growth restriction. The development of "omic" technologies presents a huge opportunity to identify novel biomarkers for fetal growth restriction. The hope is that when such markers are measured alongside ultrasonic fetal biometry, the combination would have strong predictive power for fetal growth restriction and its related complications. However, a series of important methodological considerations in assessing the diagnostic effectiveness of new tests will have to be addressed. The challenge thereafter will be to identify novel disease-modifying interventions, which are the essential partner to an effective screening test to achieve clinically effective population-based screening.
  • ItemPublished versionOpen Access
    Genome-wide oxidative bisulfite sequencing identifies sex-specific methylation differences in the human placenta.
    (Informa UK Limited, 2018) Gong, Sungsam; Johnson, Michelle D; Dopierala, Justyna; Gaccioli, Francesca; Sovio, Ulla; Constância, Miguel; Smith, Gordon Cs; Charnock-Jones, D Stephen; Gong, Sungsam [0000-0001-5796-4423]; Gaccioli, Francesca [0000-0001-7178-8921]; Sovio, Ulla [0000-0002-0799-1105]; Constância, Miguel [0000-0002-8976-1679]; Smith, Gordon Cs [0000-0003-2124-0997]; Charnock-Jones, D Stephen [0000-0002-2936-4890]
    DNA methylation is an important regulator of gene function. Fetal sex is associated with the risk of several specific pregnancy complications related to placental function. However, the association between fetal sex and placental DNA methylation remains poorly understood. We carried out whole-genome oxidative bisulfite sequencing in the placentas of two healthy female and two healthy male pregnancies generating an average genome depth of coverage of 25x. Most highly ranked differentially methylated regions (DMRs) were located on the X chromosome but we identified a 225 kb sex-specific DMR in the body of the CUB and Sushi Multiple Domains 1 (CSMD1) gene on chromosome 8. The sex-specific differential methylation pattern observed in this region was validated in additional placentas using in-solution target capture. In a new RNA-seq data set from 64 female and 67 male placentas, CSMD1 mRNA was 1.8-fold higher in male than in female placentas (P value = 8.5 × 10-7, Mann-Whitney test). Exon-level quantification of CSMD1 mRNA from these 131 placentas suggested a likely placenta-specific CSMD1 isoform not detected in the 21 somatic tissues analyzed. We show that the gene body of an autosomal gene, CSMD1, is differentially methylated in a sex- and placental-specific manner, displaying sex-specific differences in placental transcript abundance.
  • ItemPublished versionOpen Access
    Perinatal mortality associated with induction of labour versus expectant management in nulliparous women aged 35 years or over: An English national cohort study.
    (Public Library of Science (PLoS), 2017-11) Knight, Hannah E; Cromwell, David A; Gurol-Urganci, Ipek; Harron, Katie; van der Meulen, Jan H; Smith, Gordon CS; Knight, Hannah E [0000-0002-6809-2517]; Cromwell, David A [0000-0002-6516-8125]; Harron, Katie [0000-0002-3418-2856]; van der Meulen, Jan H [0000-0002-9451-2335]; Smith, Gordon CS [0000-0003-2124-0997]
    BACKGROUND: A recent randomised controlled trial (RCT) demonstrated that induction of labour at 39 weeks of gestational age has no short-term adverse effect on the mother or infant among nulliparous women aged ≥35 years. However, the trial was underpowered to address the effect of routine induction of labour on the risk of perinatal death. We aimed to determine the association between induction of labour at ≥39 weeks and the risk of perinatal mortality among nulliparous women aged ≥35 years. METHODS AND FINDINGS: We used English Hospital Episode Statistics (HES) data collected between April 2009 and March 2014 to compare perinatal mortality between induction of labour at 39, 40, and 41 weeks of gestation and expectant management (continuation of pregnancy to either spontaneous labour, induction of labour, or caesarean section at a later gestation). Analysis was by multivariable Poisson regression with adjustment for maternal characteristics and pregnancy-related conditions. Among the cohort of 77,327 nulliparous women aged 35 to 50 years delivering a singleton infant, 33.1% had labour induced: these women tended to be older and more likely to have medical complications of pregnancy, and the infants were more likely to be small for gestational age. Induction of labour at 40 weeks (compared with expectant management) was associated with a lower risk of in-hospital perinatal death (0.08% versus 0.26%; adjusted risk ratio [adjRR] 0.33; 95% CI 0.13-0.80, P = 0.015) and meconium aspiration syndrome (0.44% versus 0.86%; adjRR 0.52; 95% CI 0.35-0.78, P = 0.002). Induction at 40 weeks was also associated with a slightly increased risk of instrumental vaginal delivery (adjRR 1.06; 95% CI 1.01-1.11, P = 0.020) and emergency caesarean section (adjRR 1.05; 95% CI 1.01-1.09, P = 0.019). The number needed to treat (NNT) analysis indicated that 562 (95% CI 366-1,210) inductions of labour at 40 weeks would be required to prevent 1 perinatal death. Limitations of the study include the reliance on observational data in which gestational age is recorded in weeks rather than days. There is also the potential for unmeasured confounders and under-recording of induction of labour or perinatal death in the dataset. CONCLUSIONS: Bringing forward the routine offer of induction of labour from the current recommendation of 41-42 weeks to 40 weeks of gestation in nulliparous women aged ≥35 years may reduce overall rates of perinatal death.
  • ItemAccepted versionOpen Access
    The effect of customization and use of a fetal growth standard on the association between birthweight percentile and adverse perinatal outcome.
    (Elsevier BV, 2018-02) Sovio, Ulla; Smith, Gordon CS; Sovio, Ulla [0000-0002-0799-1105]; Smith, Gordon [0000-0003-2124-0997]
    BACKGROUND: It has been proposed that correction of offspring weight percentiles (customization) might improve the prediction of adverse pregnancy outcome; however, the approach is not accepted universally. A complication in the interpretation of the data is that the main method for calculation of customized percentiles uses a fetal growth standard, and multiple analyses have compared the results with birthweight-based standards. OBJECTIVES: First, we aimed to determine whether women who deliver small-for-gestational-age infants using a customized standard differed from other women. Second, we aimed to compare the association between birthweight percentile and adverse outcome using 3 different methods for percentile calculation: (1) a noncustomized actual birthweight standard, (2) a noncustomized fetal growth standard, and (3) a fully customized fetal growth standard. STUDY DESIGN: We analyzed data from the Pregnancy Outcome Prediction study, a prospective cohort study of nulliparous women who delivered in Cambridge, UK, between 2008 and 2013. We used a composite adverse outcome, namely, perinatal morbidity or preeclampsia. Receiver operating characteristic curve analysis was used to compare the 3 methods of calculating birthweight percentiles in relation to the composite adverse outcome. RESULTS: We confirmed previous observations that delivering an infant who was small for gestational age (<10th percentile) with the use of a fully customized fetal growth standard but who was appropriate for gestational age with the use of a noncustomized actual birthweight standard was associated with higher rates of adverse outcomes. However, we also observed that the mothers of these infants were 3-4 times more likely to be obese and to deliver preterm. When we compared the risk of adverse outcome from logistic regression models that were fitted to the birthweight percentiles that were derived by each of the 3 predefined methods, the areas under the receiver operating characteristic curves were similar for all 3 methods: 0.56 (95% confidence interval, 0.54-0.59) fully customized, 0.56 (95% confidence interval, 0.53-0.59) noncustomized fetal weight standard, and 0.55 (95% confidence interval, 0.53-0.58) noncustomized actual birthweight standard. When we classified the top 5% of predicted risk as high risk, the methods that used a fetal growth standard showed attenuation after adjustment for gestational age, whereas the birthweight standard did not. Further adjustment for the maternal characteristics, which included weight, attenuated the association with the customized standard, but not the other 2 methods. The associations after full adjustment were similar when we compared the 3 approaches. CONCLUSION: The independent association between birthweight percentile and adverse outcome was similar when we compared actual birthweight standards and fetal growth standards and compared customized and noncustomized standards. Use of fetal weight standards and customized percentiles for maternal characteristics could lead to stronger associations with adverse outcome through confounding by preterm birth and maternal obesity.
  • ItemAccepted versionOpen Access
    Birth weight to placenta weight ratio and its relationship to ultrasonic measurements, maternal and neonatal morbidity: A prospective cohort study of nulliparous women.
    (Elsevier BV, 2018-03) Salavati, N; Gordijn, SJ; Sovio, U; Zill-E-Huma, R; Gebril, A; Charnock-Jones, DS; Scherjon, SA; Smith, GCS; Sovio, Ulla [0000-0002-0799-1105]; Charnock-Jones, Stephen [0000-0002-2936-4890]; Smith, Gordon [0000-0003-2124-0997]
    INTRODUCTION: Birth weight to placenta weight (BWPW)-ratio is an indicator of the ability of the placenta to maintain adequate nutrient supply to the fetus. We sought to investigate the relationship between BWPW-ratio with fetal growth, utero-placental Doppler and neonatal and maternal morbidity. METHODS: We studied a group of 3311 women recruited to a prospective cohort study of nulliparous women (Rosie Hospital, Cambridge, UK) who delivered a live born infant at term and whose placental weight and birth weight were known. Ultrasonic indices and BWPW ratio were converted to gestational age adjusted z scores. Analysis of continuous variables was by multivariable linear regression. BWPW ratio was also categorized (lowest or highest quintile, both referent to quintiles 2 to 4) and associations with adverse outcomes analyzed using multivariable logistic regression. RESULTS: Lowest quintile of BWPW-ratio was associated (adjusted odds ratio [95% CI], P) with both neonatal morbidity (1.55 [1.12-2.14], 0.007) and maternal diabetes (1.75 [1.18-2.59], 0.005). Highest quintile of BWPW ratio was associated with a reduced risk of maternal obesity (0.71 [0.53 to 0.95], 0.02) and preeclampsia (0.51 [0.31 to 0.84], 0.008), but higher (adjusted z score [95% CI], P) uterine artery Doppler mean pulsatility index (PI) at 20 weeks of gestation (0.09 [0.01-0.18], 0.04) and umbilical artery Doppler PI at 36 weeks of gestation (0.16 [0.07-0.25], <0.001). CONCLUSION: BWPW-ratio is related to ultrasonic measurements and both neonatal and maternal morbidity. Therefore, this ratio may be an indicative marker of immediate and longer term health risks for an individual.
  • ItemPublished versionOpen Access
    Retosiban Prevents Stretch-Induced Human Myometrial Contractility and Delays Labor in Cynomolgus Monkeys.
    (The Endocrine Society, 2018-03-01) Aye, Irving LMH; Moraitis, Alexandros A; Stanislaus, Dinesh; Charnock-Jones, D Stephen; Smith, Gordon CS; Aye, Irving [0000-0003-3400-5005]; Moraitis, Alexandros [0000-0003-4634-1129]; Charnock-Jones, Stephen [0000-0002-2936-4890]; Smith, Gordon [0000-0003-2124-0997]
    CONTEXT: Stretch of the myometrium promotes its contractility and is believed to contribute to the control of parturition at term and to the increased risk of preterm birth in multiple pregnancies. OBJECTIVE: To determine the effects of the putative oxytocin receptor (OTR) inverse agonist retosiban on (1) the contractility of human myometrial explants and (2) labor in nonhuman primates. DESIGN: Human myometrial biopsies were obtained at planned term cesarean, and explants were exposed to stretch in the presence and absence of a range of drugs, including retosiban. The in vivo effects of retosiban were determined in cynomolgus monkeys. RESULTS: Prolonged mechanical stretch promoted myometrial extracellular signal-regulated kinase (ERK)1/2 phosphorylation. Moreover, stretch-induced stimulation of myometrial contractility was prevented by ERK1/2 inhibitors. Retosiban (10 nM) prevented stretch-induced stimulation of myometrial contractility and phosphorylation of ERK1/2. Moreover, the inhibitory effect of retosiban on stretch-induced ERK1/2 phosphorylation was prevented by coincubation with a 100-fold excess of a peptide OTR antagonist, atosiban. Compared with vehicle-treated cynomolgus monkeys, treatment with oral retosiban (100 to 150 days of gestational age) reduced the risk of spontaneous delivery (hazard ratio = 0.07, 95% confidence interval 0.01 to 0.60, P = 0.015). CONCLUSIONS: The OTR acts as a uterine mechanosensor, whereby stretch increases myometrial contractility through agonist-free activation of the OTR. Retosiban prevents this through inverse agonism of the OTR and, in vivo, reduced the likelihood of spontaneous labor in nonhuman primates. We hypothesize that retosiban may be an effective preventative treatment of preterm birth in high-risk multiple pregnancies, an area of unmet clinical need.
  • ItemPublished versionOpen Access
    The STRIDER trial: one step forward, one step back.
    (Elsevier BV, 2018-02) Smith, Gordon CS; Smith, Gordon [0000-0003-2124-0997]
    Severe, early onset fetal growth restriction (FGR) is characterised by a fetus presenting at a gestational age at the borderline of viability which is extremely small for gestational age by ultrasonic biometry and exhibits other signs of utero-placental insufficiency, such as abnormal patterns of uterine or umbilical blood flow. Following diagnosis, there is, currently, no disease modifying therapy other than medically indicated delivery, which carries a high risk of neonatal death or, if the infant survives, severe neurodisability in later life. Conversely, expectant management carries a substantial risk of intra-uterine fetal death. Balancing these conflicting risks is a day to day element of practice in Maternal-Fetal Medicine. Practitioners looks to a future of disease modifying therapies other than delivery. Unfortunately, the STRIDER trial suggests that one of the promising candidates, sildenafil citrate, is very unlikely to offer hope in this dismal situation. The study was powered to detect a 7 day prolongation in pregnancy. In reality, the trend was towards a reduction in the duration of pregnancy and the 95% confidence interval indicates that the best one could expect is a 1.3 day prolongation. In reality, it is more likely that the drug hastens delivery rather than postpones it.
  • ItemAccepted versionOpen Access
    Parent-of-origin-specific allelic associations among 106 genomic loci for age at menarche.
    (Springer Science and Business Media LLC, 2014-10-02) Perry, John Rb; Day, Felix; Elks, Cathy E; Sulem, Patrick; Thompson, Deborah J; Ferreira, Teresa; He, Chunyan; Chasman, Daniel I; Esko, Tõnu; Thorleifsson, Gudmar; Albrecht, Eva; Ang, Wei Q; Corre, Tanguy; Cousminer, Diana L; Feenstra, Bjarke; Franceschini, Nora; Ganna, Andrea; Johnson, Andrew D; Kjellqvist, Sanela; Lunetta, Kathryn L; McMahon, George; Nolte, Ilja M; Paternoster, Lavinia; Porcu, Eleonora; Smith, Albert V; Stolk, Lisette; Teumer, Alexander; Tšernikova, Natalia; Tikkanen, Emmi; Ulivi, Sheila; Wagner, Erin K; Amin, Najaf; Bierut, Laura J; Byrne, Enda M; Hottenga, Jouke-Jan; Koller, Daniel L; Mangino, Massimo; Pers, Tune H; Yerges-Armstrong, Laura M; Zhao, Jing Hua; Andrulis, Irene L; Anton-Culver, Hoda; Atsma, Femke; Bandinelli, Stefania; Beckmann, Matthias W; Benitez, Javier; Blomqvist, Carl; Bojesen, Stig E; Bolla, Manjeet K; Bonanni, Bernardo; Brauch, Hiltrud; Brenner, Hermann; Buring, Julie E; Chang-Claude, Jenny; Chanock, Stephen; Chen, Jinhui; Chenevix-Trench, Georgia; Collée, J Margriet; Couch, Fergus J; Couper, David; Coveillo, Andrea D; Cox, Angela; Czene, Kamila; D'adamo, Adamo Pio; Smith, George Davey; De Vivo, Immaculata; Demerath, Ellen W; Dennis, Joe; Devilee, Peter; Dieffenbach, Aida K; Dunning, Alison M; Eiriksdottir, Gudny; Eriksson, Johan G; Fasching, Peter A; Ferrucci, Luigi; Flesch-Janys, Dieter; Flyger, Henrik; Foroud, Tatiana; Franke, Lude; Garcia, Melissa E; García-Closas, Montserrat; Geller, Frank; de Geus, Eco Ej; Giles, Graham G; Gudbjartsson, Daniel F; Gudnason, Vilmundur; Guénel, Pascal; Guo, Suiqun; Hall, Per; Hamann, Ute; Haring, Robin; Hartman, Catharina A; Heath, Andrew C; Hofman, Albert; Hooning, Maartje J; Hopper, John L; Hu, Frank B; Hunter, David J; Karasik, David; Kiel, Douglas P; Knight, Julia A; Kosma, Veli-Matti; Kutalik, Zoltan; Lai, Sandra; Lambrechts, Diether; Lindblom, Annika; Mägi, Reedik; Magnusson, Patrik K; Mannermaa, Arto; Martin, Nicholas G; Masson, Gisli; McArdle, Patrick F; McArdle, Wendy L; Melbye, Mads; Michailidou, Kyriaki; Mihailov, Evelin; Milani, Lili; Milne, Roger L; Nevanlinna, Heli; Neven, Patrick; Nohr, Ellen A; Oldehinkel, Albertine J; Oostra, Ben A; Palotie, Aarno; Peacock, Munro; Pedersen, Nancy L; Peterlongo, Paolo; Peto, Julian; Pharoah, Paul Dp; Postma, Dirkje S; Pouta, Anneli; Pylkäs, Katri; Radice, Paolo; Ring, Susan; Rivadeneira, Fernando; Robino, Antonietta; Rose, Lynda M; Rudolph, Anja; Salomaa, Veikko; Sanna, Serena; Schlessinger, David; Schmidt, Marjanka K; Southey, Mellissa C; Sovio, Ulla; Stampfer, Meir J; Stöckl, Doris; Storniolo, Anna M; Timpson, Nicholas J; Tyrer, Jonathan; Visser, Jenny A; Vollenweider, Peter; Völzke, Henry; Waeber, Gerard; Waldenberger, Melanie; Wallaschofski, Henri; Wang, Qin; Willemsen, Gonneke; Winqvist, Robert; Wolffenbuttel, Bruce Hr; Wright, Margaret J; Australian Ovarian Cancer Study; GENICA Network; kConFab; LifeLines Cohort Study; InterAct Consortium; Early Growth Genetics (EGG) Consortium; Boomsma, Dorret I; Econs, Michael J; Khaw, Kay-Tee; Loos, Ruth Jf; McCarthy, Mark I; Montgomery, Grant W; Rice, John P; Streeten, Elizabeth A; Thorsteinsdottir, Unnur; van Duijn, Cornelia M; Alizadeh, Behrooz Z; Bergmann, Sven; Boerwinkle, Eric; Boyd, Heather A; Crisponi, Laura; Gasparini, Paolo; Gieger, Christian; Harris, Tamara B; Ingelsson, Erik; Järvelin, Marjo-Riitta; Kraft, Peter; Lawlor, Debbie; Metspalu, Andres; Pennell, Craig E; Ridker, Paul M; Snieder, Harold; Sørensen, Thorkild Ia; Spector, Tim D; Strachan, David P; Uitterlinden, André G; Wareham, Nicholas J; Widen, Elisabeth; Zygmunt, Marek; Murray, Anna; Easton, Douglas F; Stefansson, Kari; Murabito, Joanne M; Ong, Ken K; Perry, John [0000-0001-6483-3771]; Day, Felix [0000-0003-3789-7651]; Thompson, Deborah [0000-0003-1465-5799]; Zhao, Jing Hua [0000-0003-4930-3582]; Dennis, Joe [0000-0003-4591-1214]; Dunning, Alison [0000-0001-6651-7166]; Pharoah, Paul [0000-0001-8494-732X]; Sovio, Ulla [0000-0002-0799-1105]; Tyrer, Jonathan [0000-0003-3724-4757]; Wang, Jean [0000-0002-9139-0627]; Khaw, Kay-Tee [0000-0002-8802-2903]; Wareham, Nicholas [0000-0003-1422-2993]; Easton, Douglas [0000-0003-2444-3247]; Ong, Kenneth [0000-0003-4689-7530]
    Age at menarche is a marker of timing of puberty in females. It varies widely between individuals, is a heritable trait and is associated with risks for obesity, type 2 diabetes, cardiovascular disease, breast cancer and all-cause mortality. Studies of rare human disorders of puberty and animal models point to a complex hypothalamic-pituitary-hormonal regulation, but the mechanisms that determine pubertal timing and underlie its links to disease risk remain unclear. Here, using genome-wide and custom-genotyping arrays in up to 182,416 women of European descent from 57 studies, we found robust evidence (P < 5 × 10(-8)) for 123 signals at 106 genomic loci associated with age at menarche. Many loci were associated with other pubertal traits in both sexes, and there was substantial overlap with genes implicated in body mass index and various diseases, including rare disorders of puberty. Menarche signals were enriched in imprinted regions, with three loci (DLK1-WDR25, MKRN3-MAGEL2 and KCNK9) demonstrating parent-of-origin-specific associations concordant with known parental expression patterns. Pathway analyses implicated nuclear hormone receptors, particularly retinoic acid and γ-aminobutyric acid-B2 receptor signalling, among novel mechanisms that regulate pubertal timing in humans. Our findings suggest a genetic architecture involving at least hundreds of common variants in the coordinated timing of the pubertal transition.
  • ItemPublished versionOpen Access
    Gene network inference and visualization tools for biologists: application to new human transcriptome datasets.
    (Oxford University Press (OUP), 2012-03) Hurley, Daniel; Araki, Hiromitsu; Tamada, Yoshinori; Dunmore, Ben; Sanders, Deborah; Humphreys, Sally; Affara, Muna; Imoto, Seiya; Yasuda, Kaori; Tomiyasu, Yuki; Tashiro, Kosuke; Savoie, Christopher; Cho, Vicky; Smith, Stephen; Kuhara, Satoru; Miyano, Satoru; Charnock-Jones, D Stephen; Crampin, Edmund J; Print, Cristin G; Charnock-Jones, Stephen [0000-0002-2936-4890]
    Gene regulatory networks inferred from RNA abundance data have generated significant interest, but despite this, gene network approaches are used infrequently and often require input from bioinformaticians. We have assembled a suite of tools for analysing regulatory networks, and we illustrate their use with microarray datasets generated in human endothelial cells. We infer a range of regulatory networks, and based on this analysis discuss the strengths and limitations of network inference from RNA abundance data. We welcome contact from researchers interested in using our inference and visualization tools to answer biological questions.
  • ItemAccepted versionOpen Access
    RNA-seq reveals conservation of function among the yolk sacs of human, mouse, and chicken
    (National Academy of Sciences, 2017-06-13) Cindrova-Davies, T; Jauniaux, E; Elliot, MG; Gong, S; Burton, GJ; Charnock-Jones, DS; Cindrova-Davies, Tereza [0000-0002-9212-0514]; Gong, Sung [0000-0001-5796-4423]; Burton, Graham [0000-0001-8677-4143]; Charnock-Jones, Stephen [0000-0002-2936-4890]
    The yolk sac is phylogenetically the oldest of the extraembryonic membranes. The human embryo retains a yolk sac, which goes through primary and secondary phases of development, but its importance is controversial. Although it is known to synthesize proteins, its transport functions are widely considered vestigial. Here, we report RNA-sequencing (RNA-seq) data for the human and murine yolk sacs and compare those data with data for the chicken. We also relate the human RNA-seq data to proteomic data for the coelomic fluid bathing the yolk sac. Conservation of transcriptomes across the species indicates that the human secondary yolk sac likely performs key functions early in development, particularly uptake and processing of macro- and micronutrients, many of which are found in coelomic fluid. More generally, our findings shed light on evolutionary mechanisms that give rise to complex structures such as the placenta. We identify genetic modules that are conserved across mammals and birds, suggesting these modules are part of the core amniote genetic repertoire and are the building blocks for both oviparous and viviparous reproductive modes. We propose that although a choriovitelline placenta is never established physically in the human, the placental villi, the exocoelomic cavity, and the secondary yolk sac function together as a physiological equivalent.
  • ItemAccepted versionOpen Access
    Should we implement universal screening with late pregnancy ultrasound to prevent stillbirth?
    (Wiley, 2018-01) Smith, Gcs; Smith, Gordon [0000-0003-2124-0997]
  • ItemPublished versionOpen Access
    Physical activity attenuates the influence of FTO variants on obesity risk: a meta-analysis of 218,166 adults and 19,268 children.
    (Public Library of Science (PLoS), 2011-11) Kilpeläinen, Tuomas O; Qi, Lu; Brage, Soren; Sharp, Stephen J; Sonestedt, Emily; Demerath, Ellen; Ahmad, Tariq; Mora, Samia; Kaakinen, Marika; Sandholt, Camilla Helene; Holzapfel, Christina; Autenrieth, Christine S; Hyppönen, Elina; Cauchi, Stéphane; He, Meian; Kutalik, Zoltan; Kumari, Meena; Stančáková, Alena; Meidtner, Karina; Balkau, Beverley; Tan, Jonathan T; Mangino, Massimo; Timpson, Nicholas J; Song, Yiqing; Zillikens, M Carola; Jablonski, Kathleen A; Garcia, Melissa E; Johansson, Stefan; Bragg-Gresham, Jennifer L; Wu, Ying; van Vliet-Ostaptchouk, Jana V; Onland-Moret, N Charlotte; Zimmermann, Esther; Rivera, Natalia V; Tanaka, Toshiko; Stringham, Heather M; Silbernagel, Günther; Kanoni, Stavroula; Feitosa, Mary F; Snitker, Soren; Ruiz, Jonatan R; Metter, Jeffery; Larrad, Maria Teresa Martinez; Atalay, Mustafa; Hakanen, Maarit; Amin, Najaf; Cavalcanti-Proença, Christine; Grøntved, Anders; Hallmans, Göran; Jansson, John-Olov; Kuusisto, Johanna; Kähönen, Mika; Lutsey, Pamela L; Nolan, John J; Palla, Luigi; Pedersen, Oluf; Pérusse, Louis; Renström, Frida; Scott, Robert A; Shungin, Dmitry; Sovio, Ulla; Tammelin, Tuija H; Rönnemaa, Tapani; Lakka, Timo A; Uusitupa, Matti; Rios, Manuel Serrano; Ferrucci, Luigi; Bouchard, Claude; Meirhaeghe, Aline; Fu, Mao; Walker, Mark; Borecki, Ingrid B; Dedoussis, George V; Fritsche, Andreas; Ohlsson, Claes; Boehnke, Michael; Bandinelli, Stefania; van Duijn, Cornelia M; Ebrahim, Shah; Lawlor, Debbie A; Gudnason, Vilmundur; Harris, Tamara B; Sørensen, Thorkild IA; Mohlke, Karen L; Hofman, Albert; Uitterlinden, André G; Tuomilehto, Jaakko; Lehtimäki, Terho; Raitakari, Olli; Isomaa, Bo; Njølstad, Pål R; Florez, Jose C; Liu, Simin; Ness, Andy; Spector, Timothy D; Tai, E Shyong; Froguel, Philippe; Boeing, Heiner; Laakso, Markku; Marmot, Michael; Bergmann, Sven; Power, Chris; Khaw, Kay-Tee; Chasman, Daniel; Ridker, Paul; Hansen, Torben; Monda, Keri L; Illig, Thomas; Järvelin, Marjo-Riitta; Wareham, Nicholas J; Hu, Frank B; Groop, Leif C; Orho-Melander, Marju; Ekelund, Ulf; Franks, Paul W; Loos, Ruth JF; Brage, Soren [0000-0002-1265-7355]; Sharp, Stephen [0000-0003-2375-1440]; Sovio, Ulla [0000-0002-0799-1105]; Khaw, Kay-Tee [0000-0002-8802-2903]; Wareham, Nicholas [0000-0003-1422-2993]
    BACKGROUND: The FTO gene harbors the strongest known susceptibility locus for obesity. While many individual studies have suggested that physical activity (PA) may attenuate the effect of FTO on obesity risk, other studies have not been able to confirm this interaction. To confirm or refute unambiguously whether PA attenuates the association of FTO with obesity risk, we meta-analyzed data from 45 studies of adults (n = 218,166) and nine studies of children and adolescents (n = 19,268). METHODS AND FINDINGS: All studies identified to have data on the FTO rs9939609 variant (or any proxy [r(2)>0.8]) and PA were invited to participate, regardless of ethnicity or age of the participants. PA was standardized by categorizing it into a dichotomous variable (physically inactive versus active) in each study. Overall, 25% of adults and 13% of children were categorized as inactive. Interaction analyses were performed within each study by including the FTO×PA interaction term in an additive model, adjusting for age and sex. Subsequently, random effects meta-analysis was used to pool the interaction terms. In adults, the minor (A-) allele of rs9939609 increased the odds of obesity by 1.23-fold/allele (95% CI 1.20-1.26), but PA attenuated this effect (p(interaction)  = 0.001). More specifically, the minor allele of rs9939609 increased the odds of obesity less in the physically active group (odds ratio  = 1.22/allele, 95% CI 1.19-1.25) than in the inactive group (odds ratio  = 1.30/allele, 95% CI 1.24-1.36). No such interaction was found in children and adolescents. CONCLUSIONS: The association of the FTO risk allele with the odds of obesity is attenuated by 27% in physically active adults, highlighting the importance of PA in particular in those genetically predisposed to obesity.
  • ItemPublished versionOpen Access
    Adipose tissue dysfunction as a central mechanism leading to dysmetabolic obesity triggered by chronic exposure to p,p'-DDE
    (Nature Publishing Group, 2017-06-01) Pestana, D; Teixeira, D; Meireles, M; Marques, C; Norberto, S; Sá, C; Fernandes, VC; Correia-Sá, L; Faria, A; Guardão, L; Guimarães, JT; Cooper, WN; Sandovici, I; Domingues, VF; Delerue-Matos, C; Monteiro, R; Constância, M; Calhau, C; Cooper, Wendy [0000-0003-3416-9982]; Sandovici, Ionel [0000-0001-5674-4269]
    Endocrine-disrupting chemicals such as p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE), are bioaccumulated in the adipose tissue (AT) and have been implicated in the obesity and diabetes epidemic. Thus, it is hypothesized that p,p'-DDE exposure could aggravate the harm of an obesogenic context. We explored the effects of 12 weeks exposure in male Wistar rats' metabolism and AT biology, assessing a range of metabolic, biochemical and histological parameters. p,p'-DDE -treatment exacerbated several of the metabolic syndrome-accompanying features induced by high-fat diet (HF), such as dyslipidaemia, glucose intolerance and hypertension. A transcriptome analysis comparing mesenteric visceral AT (vAT) of HF and HF/DDE groups revealed a decrease in expression of nervous system and tissue development-related genes, with special relevance for the neuropeptide galanin that also revealed DNA methylation changes at its promoter region. Additionally, we observed an increase in transcription of dipeptidylpeptidase 4, as well as a plasmatic increase of the pro-inflammatory cytokine IL-1β. Our results suggest that p,p'-DDE impairs vAT normal function and effectively decreases the dynamic response to energy surplus. We conclude that p,p'-DDE does not merely accumulate in fat, but may contribute significantly to the development of metabolic dysfunction and inflammation. Our findings reinforce their recognition as metabolism disrupting chemicals, even in non-obesogenic contexts.