Prospective Validation of First-Trimester Screening for Preterm Preeclampsia in Nulliparous Women (PREDICTION Study).

BACKGROUND: Fetal Medicine Foundation (FMF) studies suggest that preterm preeclampsia can be predicted in the first trimester by combining biophysical, biochemical, and ultrasound markers and prevented using aspirin. We aimed to evaluate the FMF preterm preeclampsia screening test in nulliparous women. METHODS: We conducted a prospective multicenter cohort study of nulliparous women recruited at 11 to 14 weeks. Maternal characteristics, mean arterial blood pressure, PAPP-A (pregnancy-associated plasma protein A), PlGF (placental growth factor) in maternal blood, and uterine artery pulsatility index were collected at recruitment. The risk of preterm preeclampsia was calculated by a third party blinded to pregnancy outcomes. Receiver operating characteristic curves were used to estimate the detection rate (sensitivity) and the false-positive rate (1-specificity) for preterm (<37 weeks) and for early-onset (<34 weeks) preeclampsia according to the FMF screening test and according to the American College of Obstetricians and Gynecologists criteria. RESULTS: We recruited 7554 participants including 7325 (97%) who remained eligible after 20 weeks of which 65 (0.9%) developed preterm preeclampsia, and 22 (0.3%) developed early-onset preeclampsia. Using the FMF algorithm (cutoff of ≥1 in 110 for preterm preeclampsia), the detection rate was 63.1% for preterm preeclampsia and 77.3% for early-onset preeclampsia at a false-positive rate of 15.8%. Using the American College of Obstetricians and Gynecologists criteria, the equivalent detection rates would have been 61.5% and 59.1%, respectively, for a false-positive rate of 34.3%. CONCLUSIONS: The first-trimester FMF preeclampsia screening test predicts two-thirds of preterm preeclampsia and three-quarters of early-onset preeclampsia in nulliparous women, with a false-positive rate of ≈16%. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02189148.

Association between Human Papillomavirus 16 Viral Load in Pregnancy and Preterm Birth.

Recent evidence shows increased preterm birth risk with human papillomavirus-16 (HPV16) infection during pregnancy. This study aimed to measure the association between HPV16 viral load during pregnancy and preterm birth. We used data from participants in the HERITAGE study. The Linear Array assay was used for HPV DNA testing on vaginal samples collected during the first and third trimesters of pregnancy. The HPV16 viral load was measured with a real-time polymerase chain reaction. We used logistic regression to measure the associations between HPV16 viral load during pregnancy and preterm birth (defined as birth before 37 weeks of gestation). The adjusted odd ratios (aORs) and the 95% confidence intervals [CIs] were estimated with inverse probability treatment weighting of the propensity score. This study included 48 participants who tested positive for HPV16 during the first trimester of pregnancy. The aOR for the association between first-trimester HPV16 viral load (higher viral load categorized with a cutoff of 0.5 copy/cell) was 13.04 [95% CI: 1.58-107.57]). Similar associations were found using different cutoffs for the categorization of viral load during the first and third trimesters. Our findings suggest a strong association between a high HPV16 viral load during pregnancy and preterm birth, demonstrating a biological gradient that reinforces the biological plausibility of a causal association.

Association between the Mode of Delivery and Vertical Transmission of Human Papillomavirus.

Human papillomavirus (HPV) can be vertically transmitted. Our objective was to measure the association between the mode of delivery and the detection of HPV in infants. We used data collected from pregnant women during the HERITAGE study. Self-collected vaginal samples from the first and third trimester were obtained for HPV testing. Specimens from oral, pharyngeal, conjunctival and anogenital mucosa were collected from infants 36-48 h after delivery and at 3 months of age. All samples were tested for HPV DNA by the Linear Array assay. Adjusted odd ratios (aOR) and 95% confidence interval (CI) were estimated using multivariate logistic regressions. From the 282 women revealed to be HPV-positive in both the first and third trimesters, 25 infants were born HPV-positive. The overall probability of transmission was 8.9% (25/282); 3.7% (3/81) in participants with a caesarean section and 10.9% (22/201) for those who delivered vaginally. Vaginal delivery increased the risk of HPV in infants compared to caesarean (aOR: 3.63, 95%CI: 1.03-12.82). Infants born after a caesarean with ruptured membranes were not at increased risk of HPV compared to infants born after an elective caesarean section with intact membranes (aOR: 1.31, 95%CI: 0.10-17.76). Our results support the hypothesis that transmission occurs mostly during the passage in the vaginal canal.

Perinatal morbidity among women with a previous caesarean delivery (PRISMA trial): a cluster-randomised trial.

BACKGROUND: Women with a previous caesarean delivery face a difficult choice in their next pregnancy: planning another caesarean or attempting vaginal delivery, both of which are associated with potential maternal and perinatal complications. This trial aimed to assess whether a multifaceted intervention, which promoted person-centred decision making and best practices, would reduce the risk of major perinatal morbidity among women with one previous caesarean delivery. METHODS: We conducted an open, multicentre, cluster-randomised, controlled trial of a multifaceted 2-year intervention in 40 hospitals in Quebec among women with one previous caesarean delivery, in which hospitals were the units of randomisation and women the units of analysis. Randomisation was stratified according to level of care, using blocked randomisation. Hospitals were randomly assigned (1:1) to the intervention group (implementation of best practices and provision of tools that aimed to support decision making about mode of delivery, including an estimation of the probability of vaginal delivery and an ultrasound estimation of the risk of uterine rupture), or the control group (no intervention). The primary outcome was a composite risk of major perinatal morbidity. This trial was registered with ISRCTN, ISRCTN15346559. FINDINGS: 21 281 eligible women delivered during the study period, from April 1, 2016 to Dec 13, 2019 (10 514 in the intervention group and 10 767 in the control group). None were lost to follow-up. There was a significant reduction in the rate of major perinatal morbidity from the baseline period to the intervention period in the intervention group as compared with the control group (adjusted odds ratio [OR] for incremental change over time, 0·72 [95% CI 0·52-0·99]; p=0·042; adjusted risk difference -1·2% [95% CI -2·0 to -0·1]). Major maternal morbidity was significantly reduced in the intervention group as compared with the control group (adjusted OR 0·54 [95% CI 0·33-0·89]; p=0·016). Minor perinatal and maternal morbidity, caesarean delivery, and uterine rupture rates did not differ significantly between groups. INTERPRETATION: A multifaceted intervention supporting women in their choice of mode of delivery and promoting best practices resulted in a significant reduction in rates of major perinatal and maternal morbidity, without an increase in the rate of caesarean or uterine rupture. FUNDING: Canadian Institutes of Health Research (CIHR, MOP-142448).

Expansion of non-invasive prenatal screening to the screening of 10 types of chromosomal anomalies: a cost-effectiveness analysis.

OBJECTIVES: To determine the cost-effectiveness of the addition of chromosomal anomalies detectable by non-invasive prenatal screening (NIPS), in a prenatal screening programme targeting common aneuploidies. DESIGN, SETTING AND PARTICIPANTS: A simulation study was conducted to study the addition of chromosomal anomalies detectable by NIPS (sex chromosome aneuploidies, 22q11.2 deletion syndrome, large deletion/duplication >7 Mb and rare autosomal trisomies) to five basic strategies currently aiming the common trisomies: three strategies currently offered by the public healthcare systems in Canada, whose first-tier test is performed with biochemical markers, and two programmes whose first-tier test consists of NIPS-based methods. OUTCOME MEASURES: The total number of cases of chromosomal anomalies detected and the costs related to the consumption of medical services. RESULTS: The most effective and the most cost-effective option in almost all prenatal screening strategies is the option that includes all targeted additional conditions. In the strategies where NIPS is used as first-tier testing, the cost per additional case detected by adding all possible additional anomalies to a programme that currently targets only common trisomies is $C25 710 (95% CI $C25 489 to $C25 934) for massively parallel shotgun sequencing and $C57 711 (95% CI $C57 141 to $C58 292) for targeted massively parallel sequencing, respectively. The acceptability curves show that at a willingness-to-pay of $C50 000 per one additional case detected, the expansion of NIPS-based methods for the detection of all possible additional conditions has a 90% probability of being cost-effective. CONCLUSION: From an economic perspective, in strategies that use NIPS as a first-tier screening test, expanding the programmes to detect any considered chromosomal anomalies other than the three common trisomies would be cost-effective. However, the potential expansion of prenatal screening programmes also requires consideration of societal issues, including ethical ones.

Fetal Doppler in monochorionic pregnancies complicated by twin-to-twin transfusion syndrome and selective in utero growth restriction.

BACKGROUND: Monochorionic (MC) twin pregnancies may be complicated by placental pathologies that impact fetal cardiac function, such as twin-twin transfusion syndrome (TTTS) and selective intrauterine growth-restriction (sIUGR). In the TTTS, the unbalanced blood flow through placental anastomoses lead a recipient volume overload, hypertension and hypertrophic cardiomyopathy and the donor twin experiences hypovolemia and hypertension due to increased placental resistance and poor renal perfusion. When MC pregnancies were complicated by sIUGR, the increase of placental resistances lead to complex fetal compensatory mechanisms with redistribution of cardiac output to vital organs. Increased placental vascular resistances, hypoxia and hemodynamic compensation mechanisms lead to higher pre and/or afterload for both ventricles, right cardiac failure and eventually left cardiac failure observed just before fetal death. OBJECTIVES: The purpose of this study was to describe the anomalies of umbilical, ductal and aortic isthmic Doppler as well as left and right myocardial performance index (MPI) across various clinical phenotypes of MC twin pregnancies, uncomplicated or complicated by TTTS or sIUGR, in order to help differentiating these conditions and to improve the understanding of TTTS and sIUGR pathophysiology. STUDY DESIGN: Aortic isthmic systolic index (ISI), umbilical artery pulsatility index (UAPI), ductus venosus pulsatility index (DVPI), and MPI were studied in uncomplicated MC twins (control group) and cases of sIUGR or TTTS. RESULTS: The measurements were obtained in 113 pregnancies (24 uncomplicated, 22 sIUGR, 51 TTTS). In comparison with controls, the sIUGR smaller twin sets had lower ISI and higher UAPI, and the larger twin had higher ISI. The TTTS donor and recipient had lower ISI, higher UAPI and DVPI. Compared to the co-twin, the ISI values were lower in the sIUGR smaller twin and the TTTS donor had lower ISI and MPI. Comparing TTTS and sIUGR, the recipient had higher DVPI and MPI than the sIUGR larger twin. CONCLUSIONS: The Doppler anomalies observed in the smaller twin reflected increased placental blood flow resistance, presumably due to abnormal feto-fetal transfusion in TTTS and to unequal placental sharing in sIUGR. Early hemodynamic changes suggestive of cardiac overload in the recipient twin may help to differentiate TTTS and sIUGR.

Human Papillomavirus Transmission and Persistence in Pregnant Women and Neonates.

Importance: The prevalence of human papillomavirus (HPV) infection during pregnancy and its risk of transmission to newborns are not well documented. Objective: To ascertain the prevalence of HPV in pregnant women, the risk of HPV detection in the placenta and in children at birth, and the probability that HPV detected at birth may persist in newborns. Design, Setting, and Participants: The Human Papillomavirus Perinatal Transmission and Risk of HPV Persistence Among Children (HERITAGE) study was a prospective cohort study that recruited participants between November 8, 2010, and October 16, 2016. Participant follow-up visits were completed on June 15, 2017. Participants, which included pregnant women of at least 18 years of age and at 14 weeks or earlier of gestation, were recruited from 3 academic hospitals in Montreal, Québec, Canada. Laboratory and statistical analysis were completed on November 15, 2022. Exposures: HPV DNA testing on self-collected vaginal and placental samples. Among children of mothers positive for HPV, conjunctival, oral, pharyngeal, and genital samples were collected for HPV DNA testing. Main Outcomes and Measures: Vaginal HPV DNA testing was done on self-collected vaginal samples obtained among pregnant women recruited during their first trimester of pregnancy and in the third trimester for those who had HPV-positive samples in the first trimester. HPV DNA testing was also done on placental samples (swabs and biopsies) collected after birth in all participants. HPV DNA testing among children included conjunctival, oral, pharyngeal, and genital samples collected in children of HPV-positive mothers at birth, 3 months, and 6 months of age. Results: A total of 1050 pregnant women (mean [SD] age, 31.3 [4.7] years) were included in this study. Prevalence of HPV in pregnant women at recruitment was 40.3% (95% CI, 37.3%-43.3%). Among the 422 HPV-positive women, 280 (66.4%) harbored at least 1 high-risk genotype, and 190 (45.0%) were coinfected with multiple genotypes. HPV was detected in 10.7% of placentas (92 of 860; 95% CI, 8.8%-12.9%) overall, but only 3.9% of biopsies (14 of 361) on the fetal side under the amniotic membrane were positive. Neonatal HPV detection (at birth and/or at 3 months) was 7.2% (95% CI, 5.0%-10.3%) overall, with the most frequent site of infection being the conjunctiva (3.2%; 95% CI, 1.8%-5.6%), followed by the mouth (2.9%; 95% CI, 1.6%-5.2%), the genital area (2.7%; 95% CI, 1.4%-4.9%), and the pharynx (0.8%; 95% CI, 0.2%-2.5%). Importantly, all HPV detected in children at birth cleared before the age of 6 months. Conclusions and relevance: In this cohort study, vaginal HPV was frequently detected in pregnant women. Perinatal transmission was infrequent, and in this cohort, no infection detected at birth persisted at 6 months. Although HPV was detected in placentas, it remains difficult to differentiate contamination vs true infection.

First-trimester screening for Down syndrome using quadruple maternal biochemical markers.

OBJECTIVES: Placental growth factor (PlGF) is used for first-trimester preeclampsia screening and could be combined with other biochemical markers for Down syndrome screening. We aim to estimate the predictive value of the combination of pregnancy-associated plasma protein (PAPP-A), free ß-human chorionic gonadotropin (free ß-hCG), placental growth factor (PlGF) and α-fetoprotein (AFP) with and without nuchal translucency. METHODS: Singleton pregnancies recruited at 11-14 weeks and followed until delivery. The four maternal markers were measured using Kryptor (ThermoFisher-BRAHMS) and adjusted for gestational age and maternal characteristics. The risk of Down syndrome was calculated using the Fetal Medicine Foundation algorithm and multivariate linear regression analyses in all cases and in 2,200 controls. Receiver-operator characteristic (ROC) curves were used to calculate the detection and false-positive rates. RESULTS: Twenty-six (0.2%) cases of Down syndrome were diagnosed among 13,386 participants. The combination of the four biomarkers could have detected 88% (95% CI: 72-97%) of the cases at a false-positive rate of 13% (95% CI: 12-15%). The addition of nuchal translucency would have increased the detection rate to 96% (95% CI: 82-99%) at a false-positive rate of 4% (95% CI: 4-5%) using a 1:300 cut-off and to 100% (95% CI: 89-100%) at a false-positive rate of 6% (95% CI: 5-8%) using a 1:500 cut-off. CONCLUSIONS: First-trimester screening using biochemical markers allows the identification of approximately 88% of Down syndrome cases for a false-positive rate of 13%. The addition of nuchal translucency raises the detection rate above 95% with a false-positive rate below 5%.

Impact of Selective Fetal Growth Restriction on Laser Therapy Outcomes in Twin-Twin Transfusion Syndrome.

INTRODUCTION: The aim of this study was to determine if outcomes of fetoscopic laser photocoagulation in isolated twin-twin transfusion syndrome (TTTS) differ from TTTS with concomitant selective fetal growth restriction (sFGR). METHODS: This is a retrospective cohort study of all cases of TTTS treated at the CHU Sainte-Justine between February 2006 and January 2020. Data were collected from maternal, obstetrical, and neonatal chart review. RESULTS: A total of 149 patients were included in our study. Forty-seven patients (31.5%) had a pregnancy complicated by TTTS and sFGR. Mean gestational age at diagnosis and at treatment was 20+4 weeks and 20+6 weeks for TTTS alone, and 20+5 weeks and 21+2 weeks with concomitant sFGR. The presence of concomitant sFGR negatively impacted survival. Double survival in the TTTS + sFGR was 48.9% (23/47) versus 68.6% (70/102) in the TTTS-only group (p = 0.021). Fetal donor survival was 59.6% (28/47) in the TTTS + sFGR group and 84.3% (86/102) in the TTTS-only group (p = 0.001). However, the survival of at least one twin did not differ between the two groups: 93.6% (44/47) in the TTTS + sFGR group versus 92.2% (94/102) in the TTTS-only group (p = 0.751). The presence of type 2-3 sFGR (OR = 0.56; 95% CI 0.32-0.96, p = 0.033) and gestational age at laser therapy (OR = 1.17; 95% CI 1.01 = 1.36, p = 0.036) were independently associated with dual survival. CONCLUSION: sFGR is independently associated with decreased double survivorship at the expense of the donor in TTTS undergoing laser therapy. Type 2 or 3 sFGR and early gestational age at treatment are especially at risk. A larger cohort is needed to validate our results.

Optimal Gestational Weight Gain for Women With Obesity.

OBJECTIVE: To determine the optimal gestational weight gain interval for women with obesity in order to minimize neonatal and maternal adverse events. METHODS: Secondary analysis of the QUARISMA trial, including women with obesity who delivered a full-term singleton in cephalic presentation from 2008 to 2011 in Québec. The primary outcome was a composite risk of major neonatal morbidity. Secondary outcomes were composite risks of major maternal morbidity, minor neonatal and maternal morbidity, and cesarean delivery. Various ranges of weight gain were compared with the current recommendations (reference group) using logistic regression to identify an optimal gestational weight gain interval. In a secondary analysis, women with obesity were stratified by obesity class (I-III). RESULTS: Among 16 808 eligible women with obesity, 3270 gained less weight than recommended, 4355 gained weight as recommended (5-9.09 kg), and 9183 gained more weight than recommended. Optimal gestational weight change for all women with obesity was -1 to +4 kg and was associated with reduced risk of major neonatal morbidity (aOR 0.49; 95%CI 0.33-0.73, P < 0.001) compared with the reference group. Analysis by class of obesity showed a reduced risk of major neonatal morbidity with a weight change of -1 to +4 kg for class I, -2 to +2 for class II), and -2 to +3 kg for class III. CONCLUSION: Compared with the current guidelines, a gestational weight change of -1 to +4 kg is associated with reduced risk of adverse perinatal outcomes. While similar findings were seen among women with class I obesity, women with class II or III obesity could benefit from a lower weight gain.

Halting the Canadian STRIDER randomised controlled trial of sildenafil for severe, early-onset fetal growth restriction: ethical, methodological, and pragmatic considerations.

OBJECTIVES: To determine the efficacy and safety of sildenafil citrate to improve outcomes in pregnancies complicated by early-onset, dismal prognosis, fetal growth restriction (FGR). Eligibility: women ≥ 18 years, singleton, 18 + 0-27 + 6 weeks' gestation, estimated fetal weight < 700 g, low PLFG, and ≥ 1 of (i) abdominal circumference < 10th percentile for gestational age (GA); or (ii) reduced growth velocity and either abnormal uterine artery Doppler or prior early-onset FGR with adverse outcome. Ineligibility criteria included: planned termination or reversed umbilical artery end-diastolic flow. Eligibility confirmed by placental growth factor (PLGF) < 5 th percentile for GA measured post randomization. Women randomly received (1:1) either sildenafil 25 mg three times daily or matched placebo until either delivery or 31 + 6 weeks. PRIMARY OUTCOME: delivery GA. The trial stopped early when Dutch STRIDER signalled potential harm; despite distinct eligibility criteria and IRB and DSMB support to continue, because of futility. NCT02442492 [registered 13/05/2015]. RESULTS: Between May 2017 and June 2018, 21 (90 planned) women were randomised [10 sildenafil; 11 placebo (1 withdrawal)]. Baseline characteristics, PLGF levels, maternal and perinatal outcomes, and adverse events did not differ. Delivery GA: 26 + 6 weeks (sildenafil) vs 29 + 2 weeks (placebo); p = 0.200. Data will contribute to an individual participant data meta-analysis.

Impact of Gestational Weight Gain Recommendations for Obese Women on Neonatal Morbidity.

INTRODUCTION: In 2013, the American College of Obstetricians and Gynecologists (ACOGs) developed gestational weight gain guidelines to minimize the risks associated with obesity during pregnancy. However, a growing body of evidence suggests that current recommendations should be revised for obese women. OBJECTIVES: The objective of this study is to assess the impact of gestational weight gain recommendations for obese women (body mass index ≥ 30 kg/m2) on neonatal and maternal outcomes in Quebec. STUDY DESIGN: Secondary analysis of the QUARISMA trial was performed including obese women who delivered a full-term singleton in cephalic presentation from 2008 to 2011 in Quebec. Outcomes assessed were composite risks of major neonatal and maternal complications, minor neonatal and maternal complications, as well as obstetrical interventions. Outcomes were compared between weight gain recommendations (reference group) and three weight gain/loss categories using logistic regressions. In second analysis, obese women were stratified by obesity class. RESULTS: Among the 16,808 eligible obese women, 605 lost weight during pregnancy, 2,665 gained between 0 and 4.9 kg, 4,355 gained weight within the recommendations (5-9.09 kg), and 9,183 gained at least 9.1 kg. Results showed a significant reduction in major neonatal morbidity (adjusted odds ratio [aOR] = 0.69, 95% confidence interval [CI] = 0.51-0.94), minor maternal morbidity (aOR = 0.79, 95%CI = 0.67-0.93), and assisted vaginal delivery (aOR = 0.82, 95%CI = 0.68-0.99) among women who gained 0 to 4.9 kg compared with the reference group. Cesarean delivery and preeclampsia/eclampsia were significantly reduced with weight loss (aOR = 0.76, 95%CI = 0.64-0.89 and 0.58, 95%CI = 0.42-0.78) compared with the reference group. Weight gain above recommendations was associated with an increased risk of minor neonatal morbidity, major and minor maternal morbidity, as well as cesarean delivery. CONCLUSIONS: Compared with a weight gain within the recommendations, a gestational weight gain/loss of less than 5 kg in obese women is associated with a reduced risk of major neonatal morbidity, minor maternal morbidity, preeclampsia/eclampsia, cesarean delivery, and assisted vaginal delivery. Guidelines on gestational weight gain for obese women should be updated. KEY POINTS: · Gestational weight gain/loss of less than 5 kg reduces the risk of perinatal complications.. · As suggested by ACOG recommendations, guidelines for obese women should be updated.. · Recommendations stratified by obesity class should be included in revised guidelines..

Risk factors for placental human papillomavirus infection.

OBJECTIVE: Human papillomavirus (HPV) has been associated with adverse pregnancy outcomes but placental HPV infection has been rarely studied. The objective was to determine the proportion of HPV-positive placentas and the associated risk factors among HPV-positive women during pregnancy. METHODS: We analysed data from pregnant women enrolled in HERITAGE cohort study between 2010 and 2016 with positive vaginal HPV infection during the first trimester of pregnancy (n=354). Placental swabs and biopsies were collected. HPV genotyping was performed using Linear Array. The predictors of placental HPV detection were identified by generalised estimating equations models. RESULTS: HPV was detected in 78 placentas (22.0%) (one among 96 caesarean sections and 77 among 258 vaginal deliveries). Overall, 91% of HPV-positive placentas were positive for a genotype that was detected in vaginal samples during pregnancy. Among women who delivered vaginally, abnormal cytology (adjusted OR (aOR) 1.78 (95% CI 1.02 to 3.10)), other genitourinary infection (aOR 2.41 (95% CI 1.31 to 4.44)), presence of multiple HPV genotypes in the first trimester (aOR 2.69 (95% CI 1.76 to 4.12)) and persistence of high-risk HPV infections during pregnancy (HPV-16/18: aOR 3.94 (95% CI 2.06 to 7.55) and other than HPV-16/18: aOR 2.06 (95% CI 1.05 to 4.02)) were independently associated with placental HPV. CONCLUSIONS: HPV was frequently detected in the placenta of women who delivered vaginally and may be associated with host immune response characteristics.

Association Between Human Papillomavirus Infection Among Pregnant Women and Preterm Birth.

Importance: Preterm birth remains a leading cause of perinatal mortality and lifelong morbidity worldwide. The cause of most preterm births is unknown, although several infectious processes have been implicated. Objective: To assess whether human papillomavirus (HPV) infection, a frequent infection among women of childbearing age, is associated with preterm birth. Design, Setting, and Participants: The prospective HERITAGE cohort study was conducted at 3 academic hospitals in Montreal, Québec, Canada, among 899 pregnant women recruited between November 8, 2010, and October 16, 2016. Follow-up was completed on June 15, 2017. Statistical analysis was conducted from February 6, 2020, to January 21, 2021. Exposures: Vaginal HPV DNA detection in the first and third trimesters of pregnancy and placental HPV infection. Main Outcomes and Measures: The main outcome was preterm birth (defined as a live birth or stillbirth between 20 weeks and 0 days and 36 weeks and 6 days of gestation). The association between HPV DNA detection and preterm birth was measured using logistic regression. Odds ratios (ORs) and 95% CIs were adjusted by inverse probability of treatment weights of the propensity score. Results: The study included 899 women (mean [SD] age, 31.3 [4.6] years [range, 19-47 years]) with singleton pregnancies. A total of 378 women (42.0%) had HPV DNA detected in vaginal samples collected during the first trimester, and it was detected in 91 of 819 placentas (11.1%) at delivery. Fifty-five participants experienced preterm birth (38 spontaneous and 17 medically indicated). Persistent vaginal HPV-16/18 detection was significantly associated with all preterm births (adjusted OR [aOR], 3.72; 95% CI, 1.47-9.39) and spontaneous preterm births (aOR, 3.32; 95% CI, 1.13-9.80), as was placental HPV infection (all preterm births: aOR, 2.53; 95% CI, 1.06-6.03; spontaneous preterm births: aOR, 2.92; 95% CI, 1.09-7.81). Results were similar when restricting the analysis to participants without a history of cervical intraepithelial neoplasia treatment. Conclusions and Relevance: The study's results suggest that persistent HPV-16/18 infection is associated with an increased risk of preterm birth, independent of cervical treatment. Future studies should investigate the association of HPV vaccination and vaccination programs with the risk of preterm birth.

The plasma antioxidant vitamin status of the INTAPP cohort examined: The unsuspected importance of ß-carotene and γ-tocopherol in preeclampsia.

OBJECTIVE: Examine the levels of plasma antioxidant vitamins before and during a treatment with placebo or vitamin E + C supplement to prevent preeclampsia (PE). STUDY DESIGN: Per-protocol analysis of a subset group of pregnant women (n = 295) from the International Trial of Antioxidants for the Prevention of PE (INTAPP) randomized case-control study. Normotensive receiving placebo or vitamins (n = 115 and 87 respectively) were compared to gestational hypertension (GH) without proteinuria (n = 30 and 27) and PE (n = 21 and 15). Vitamin quantification was performed at 12-18, 24-26 and 32-34 weeks of gestation. MAIN OUTCOME MEASURES: Coenzyme (Co) Q10, ß-carotene and vitamins E (α and γ forms) plasma levels. RESULTS: Vitamin E + C supplementation was found to increase the α-tocopherol levels by 40% but was associated with a 57% decrease in the γ-tocopherol isoform for all study groups (p < 0.001). The ß -carotene was lower in the PE than in the normotensive and GH groups (p < 0.001) while the level of CoQ10 remained unaffected. CONCLUSIONS: A more personalized approach that target the suboptimal levels of specific antioxidants without disturbing the α/γ-tocopherol ratio could be a more successful approach to counteract oxidative stress in PE.

Maternal vitamin D, oxidative stress, and pre-eclampsia.

OBJECTIVE: To examine the associations between risk of pre-eclampsia and pregnancy levels of maternal 25-hydroxyvitamin D (25[OH]D) and oxidative stress biomarkers. METHODS: A nested case-control study (n = 99; 34 cases; 65 controls) within a prospective pregnancy cohort. Maternal 25(OH)D and oxidative stress markers (six isomers of F2 -isoprostanes; F2 -isoPs) were measured in plasma at 12-18 and 24-26 gestational weeks. Vitamin D deficiency was defined as 25[OH]D less than 50 nmol/L. RESULTS: Maternal vitamin D deficiency was associated with increased 8-iso-PGF2α (P = 0.037), 15(R)-PGF2α (P = 0.004), (±)5-iPF2α -VI (P = 0.026) at 12-18 weeks. Vitamin D deficiency was inversely associated with 8-iso-PGF2α (P = 0.019) and (±)5-iPF2α -VI isomer (P = 0.010) at 24-26 weeks. Both maternal vitamin D deficiency (adjusted odds ratio [aOR], 4.79; 95% confidence interval [CI], 1.67-13.75) and increased (±)5-iPF2α -VI (aOR, 2.46; 95% CI, 1.16-5.22) at 24-26 weeks were associated with risk of pre-eclampsia. However, the interaction test between 25(OH)D and (±)5-iPF2α -VI was not significant (P = 0.143). CONCLUSION: Plasma 25(OH)D below 50 nmol/L was associated with increased oxidative stress levels during pregnancy as measured by two F2 -isoP isomers, including the well-studied marker 8-iso-PGF2α . Whether vitamin D-induced oxidative stress mediates the risk of pre-eclampsia warrants future study.

Validation and development of models using clinical, biochemical and ultrasound markers for predicting pre-eclampsia: an individual participant data meta-analysis.

BACKGROUND: Pre-eclampsia is a leading cause of maternal and perinatal mortality and morbidity. Early identification of women at risk is needed to plan management. OBJECTIVES: To assess the performance of existing pre-eclampsia prediction models and to develop and validate models for pre-eclampsia using individual participant data meta-analysis. We also estimated the prognostic value of individual markers. DESIGN: This was an individual participant data meta-analysis of cohort studies. SETTING: Source data from secondary and tertiary care. PREDICTORS: We identified predictors from systematic reviews, and prioritised for importance in an international survey. PRIMARY OUTCOMES: Early-onset (delivery at < 34 weeks' gestation), late-onset (delivery at ≥ 34 weeks' gestation) and any-onset pre-eclampsia. ANALYSIS: We externally validated existing prediction models in UK cohorts and reported their performance in terms of discrimination and calibration. We developed and validated 12 new models based on clinical characteristics, clinical characteristics and biochemical markers, and clinical characteristics and ultrasound markers in the first and second trimesters. We summarised the data set-specific performance of each model using a random-effects meta-analysis. Discrimination was considered promising for C-statistics of ≥ 0.7, and calibration was considered good if the slope was near 1 and calibration-in-the-large was near 0. Heterogeneity was quantified using I2 and τ2. A decision curve analysis was undertaken to determine the clinical utility (net benefit) of the models. We reported the unadjusted prognostic value of individual predictors for pre-eclampsia as odds ratios with 95% confidence and prediction intervals. RESULTS: The International Prediction of Pregnancy Complications network comprised 78 studies (3,570,993 singleton pregnancies) identified from systematic reviews of tests to predict pre-eclampsia. Twenty-four of the 131 published prediction models could be validated in 11 UK cohorts. Summary C-statistics were between 0.6 and 0.7 for most models, and calibration was generally poor owing to large between-study heterogeneity, suggesting model overfitting. The clinical utility of the models varied between showing net harm to showing minimal or no net benefit. The average discrimination for IPPIC models ranged between 0.68 and 0.83. This was highest for the second-trimester clinical characteristics and biochemical markers model to predict early-onset pre-eclampsia, and lowest for the first-trimester clinical characteristics models to predict any pre-eclampsia. Calibration performance was heterogeneous across studies. Net benefit was observed for International Prediction of Pregnancy Complications first and second-trimester clinical characteristics and clinical characteristics and biochemical markers models predicting any pre-eclampsia, when validated in singleton nulliparous women managed in the UK NHS. History of hypertension, parity, smoking, mode of conception, placental growth factor and uterine artery pulsatility index had the strongest unadjusted associations with pre-eclampsia. LIMITATIONS: Variations in study population characteristics, type of predictors reported, too few events in some validation cohorts and the type of measurements contributed to heterogeneity in performance of the International Prediction of Pregnancy Complications models. Some published models were not validated because model predictors were unavailable in the individual participant data. CONCLUSION: For models that could be validated, predictive performance was generally poor across data sets. Although the International Prediction of Pregnancy Complications models show good predictive performance on average, and in the singleton nulliparous population, heterogeneity in calibration performance is likely across settings. FUTURE WORK: Recalibration of model parameters within populations may improve calibration performance. Additional strong predictors need to be identified to improve model performance and consistency. Validation, including examination of calibration heterogeneity, is required for the models we could not validate. STUDY REGISTRATION: This study is registered as PROSPERO CRD42015029349. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 72. See the NIHR Journals Library website for further project information.

WHAT IS THE PROBLEM?: Pre-eclampsia, a condition in pregnancy that results in raised blood pressure and protein in the urine, is a major cause of complications for the mother and baby. WHAT IS NEEDED?: A way of accurately identifying women at high risk of pre-eclampsia to allow clinicians to start preventative interventions such as administering aspirin or frequently monitoring women during pregnancy. WHERE ARE THE RESEARCH GAPS?: Although over 100 tools (models) have been reported worldwide to predict pre-eclampsia, to date their performance in women managed in the UK NHS is unknown. WHAT DID WE PLAN TO DO?: We planned to comprehensively identify all published models that predict the risk of pre-eclampsia occurring at any time during pregnancy and to assess if this prediction is accurate in the UK population. If the existing models did not perform satisfactorily, we aimed to develop new prediction models. WHAT DID WE FIND?: We formed the International Prediction of Pregnancy Complications network, which provided data from a large number of studies (78 studies, 25 countries, 125 researchers, 3,570,993 singleton pregnancies). We were able to assess the performance of 24 out of the 131 models published to predict pre-eclampsia in 11 UK data sets. The models did not accurately predict the risk of pre-eclampsia across all UK data sets, and their performance varied within individual data sets. We developed new prediction models that showed promising performance on average across all data sets, but their ability to correctly identify women who develop pre-eclampsia varied between populations. The models were more clinically useful when used in the care of first-time mothers pregnant with one child, compared to a strategy of treating them all as if they were at high-risk of pre-eclampsia. WHAT DOES THIS MEAN?: Before using the International Prediction of Pregnancy Complications models in various populations, they need to be adjusted for characteristics of the particular population and the setting of application.

External validation of prognostic models predicting pre-eclampsia: individual participant data meta-analysis.

BACKGROUND: Pre-eclampsia is a leading cause of maternal and perinatal mortality and morbidity. Early identification of women at risk during pregnancy is required to plan management. Although there are many published prediction models for pre-eclampsia, few have been validated in external data. Our objective was to externally validate published prediction models for pre-eclampsia using individual participant data (IPD) from UK studies, to evaluate whether any of the models can accurately predict the condition when used within the UK healthcare setting. METHODS: IPD from 11 UK cohort studies (217,415 pregnant women) within the International Prediction of Pregnancy Complications (IPPIC) pre-eclampsia network contributed to external validation of published prediction models, identified by systematic review. Cohorts that measured all predictor variables in at least one of the identified models and reported pre-eclampsia as an outcome were included for validation. We reported the model predictive performance as discrimination (C-statistic), calibration (calibration plots, calibration slope, calibration-in-the-large), and net benefit. Performance measures were estimated separately in each available study and then, where possible, combined across studies in a random-effects meta-analysis. RESULTS: Of 131 published models, 67 provided the full model equation and 24 could be validated in 11 UK cohorts. Most of the models showed modest discrimination with summary C-statistics between 0.6 and 0.7. The calibration of the predicted compared to observed risk was generally poor for most models with observed calibration slopes less than 1, indicating that predictions were generally too extreme, although confidence intervals were wide. There was large between-study heterogeneity in each model's calibration-in-the-large, suggesting poor calibration of the predicted overall risk across populations. In a subset of models, the net benefit of using the models to inform clinical decisions appeared small and limited to probability thresholds between 5 and 7%. CONCLUSIONS: The evaluated models had modest predictive performance, with key limitations such as poor calibration (likely due to overfitting in the original development datasets), substantial heterogeneity, and small net benefit across settings. The evidence to support the use of these prediction models for pre-eclampsia in clinical decision-making is limited. Any models that we could not validate should be examined in terms of their predictive performance, net benefit, and heterogeneity across multiple UK settings before consideration for use in practice. TRIAL REGISTRATION: PROSPERO ID: CRD42015029349 .

Hypertension Canada's 2020 Comprehensive Guidelines for the Prevention, Diagnosis, Risk Assessment, and Treatment of Hypertension in Adults and Children.

Hypertension Canada's 2020 guidelines for the prevention, diagnosis, risk assessment, and treatment of hypertension in adults and children provide comprehensive, evidence-based guidance for health care professionals and patients. Hypertension Canada develops the guidelines using rigourous methodology, carefully mitigating the risk of bias in our process. All draft recommendations undergo critical review by expert methodologists without conflict to ensure quality. Our guideline panel is diverse, including multiple health professional groups (nurses, pharmacy, academics, and physicians), and worked in concert with experts in primary care and implementation to ensure optimal usability. The 2020 guidelines include new guidance on the management of resistant hypertension and the management of hypertension in women planning pregnancy.

Antibodies to human papillomavirus types 6, 11, 16 and 18: Vertical transmission and clearance in children up to two years of age.

Background: There is a paucity of data on the dynamics of human papillomavirus (HPV) antibodies in children. We aimed to describe the vertical transmission and clearance of antibodies against HPV6, 11, 16 and 18 in children. Methods: We used data from pregnant women recruited into the HERITAGE cohort study between 2009 and 2012 who were positive for HPV-DNA at baseline. Dried blood spots were collected during the first trimester in pregnant participants, and at birth, 6, 12, and 24 months of age in children. The level of total immunoglobulin G (IgG) against HPV6, 11, 16 and 18 were measured using Luminex immunoassays. Spearman's coefficients were used to correlate HPV antibody levels between newborns and mothers. Panel and Kaplan-Meier graphics described antibody dynamics in the first 24 months of life. Findings: Antibodies from newborns and mothers (n = 58 pairs) were moderately to highly correlated with coefficients of 0·81 (95% confidence intervals (CI):0·70-0·88), 0·68 (95% CI:0·5-0·80), 0·90 (95% CI:0·83-0·94) and 0·85 (95% CI:0·76-0·91) against HPV6, 11, 16 and 18, respectively. In newborns seropositive at birth, anti-HPV antibodies were cleared by 80% and 100% at 12 and 24 months, respectively. Only two children presented detectable HPV antibodies at 24 months. The first child had no detectable antibodies at birth and the second presented increasing levels after two undetected measures. Interpretation: Correlation between mother and newborn IgG antibodies against HPV suggests vertical transfer. Most children cleared anti-HPV antibodies within six to 12 months. Funding: The Canadian Institutes of Health Research (CIHR).