Low-risk Singleton Pregnancies Research Articles

2637. Third Trimester Immunization with an Respiratory Syncytial Virus F Protein Vaccine for the Prevention of RSV Lower Respiratory Tract Infection in Infants

BackgroundRespiratory syncytial virus (RSV) is the leading viral cause of severe lower respiratory tract infection (LRTI) in infants worldwide, with severe disease occurring in the first months of life. We assessed the efficacy of maternal immunization with an RSV F protein vaccine against RSV LRTI over the first 180 days of life.MethodsWe enrolled 4,636 women with low-risk third trimester singleton pregnancies in 11 countries to receive RSV F vaccine or placebo in a randomized, observer-blind trial. Women were followed for 6 months post-delivery, and infants for ~1 year. Surveillance for RSV LRTI in infants, identified by RT–PCR detection of RSV, physical examination, and pulse oximetry, was carried out for 180 days from delivery.ResultsThe RSV F vaccine induced modest reactogenicity and no excess fever. Live births resulted from 98.7% of pregnancies, with no difference between treatment groups in prematurity (< 37 weeks) or mean interval from treatment to delivery. There were no apparent negative impacts on pregnancy, delivery, or infant well-being. Vaccine immunogenicity resembled that in non-pregnant women. Transplacental transfer of vaccine-induced antibodies was markedly more efficient when the interval from immunization to delivery was ≥30 days. 85 to 95% of primary and secondary endpoint RSV LRTI events in the placebo group occurred in the first 90 days of life (see Figure 1). Overall, through 180 days of infant life, RSV was associated with 11.3% of all acute respiratory illnesses and 16.7% of all LRTI, but 49.1% of LRTI with SpO2 < 95% or tachypnea, and 60.3% of all LRTI with SpO2 < 92% in the placebo group. Vaccine efficacy was greatest in the first 75 days of life but clearly persisted to the primary, per-protocol analysis at 90 days, and was supported by the ITT analysis, per Table 1. Efficacy against all-cause LRTI with severe hypoxemia (46.0%) or hospitalization (27.8%) was observed in the per-protocol population, as well as an apparent impact on the clinical diagnosis of pneumonia through both 180 and 364 days.ConclusionRSV F vaccine in the third trimester was safe and had clinically-meaningful impacts on RSV and all-cause LRTI over the first 6 months of life. Disclosures All authors: No reported disclosures.

Z Score Reference Ranges of Fetal Cardiac Output From 12 to 40 Weeks of Pregnancy.

To develop the Z score reference ranges of fetal cardiac output (CO) in healthy fetuses from 12 to 40 weeks of pregnancy. A cross-sectional descriptive study was undertaken among low-risk singleton pregnancies with healthy fetuses between 12 and 40 weeks. The right ventricular cardiac output (RCO), left ventricular cardiac output (LCO), and combined cardiac output (CCO) were measured by 2-dimensional ultrasound with the Doppler velocity of the aorta and pulmonary arteries. The pregnancies were followed until delivery RESULTS: The RCO, LCO, and CCO were determined in 700 fetuses. The predictive models of the CO as a function of gestational age (GA) and biparietal diameter were identified, and the Z score reference ranges were constructed. The means and standard deviations of CO on both sides were increased with GA and biparietal diameter as power models. Nomograms for the LCO, RCO, and CCO were established (ie, RCO = 0.000148 × GA4.283034 ; SD = 0.000131 × GA4.026209 ; LCO = 0.000514 × GA3.790944 ; SD = 0.000169 × GA3.815546 ). The RCO was much more increased than the LCO with advancing GA. The Z score reference ranges and percentile charts of fetal CO were constructed throughout gestation with a large sample size. This may be helpful in detection of cardiac disorders, especially cardiomyopathy, cardiac anomalies, fetal anemia, and fetal growth restriction.

Sexual Intercourse for Induction of Spontaneous Onset of Labor: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

IntroductionSexual intercourse during pregnancy is commonly believed to trigger the onset of contractions and, therefore, labor. However, in low-risk pregnancies, there is neither association with preterm birth, premature rupture of membranes, or low birth weight, nor with spontaneous onset of labor at term. AimTo evaluate the effectiveness of sexual intercourse for spontaneous onset of labor at term in singleton pregnancies. MethodsThe systematic search was conducted using electronic databases from inception of each database to June 2019. Review of articles also included the abstracts of all references retrieved from the search. Inclusion criteria were randomized controlled trials comparing sexual intercourse in singleton low-risk pregnancies at term with controls (either reduced number of coitus or no coitus) for spontaneous onset of labor. Estimates were pooled using random-effects meta-analysis. Main Outcome MeasuresThe primary outcome was the incidence of spontaneous onset of labor. The summary measures were reported as summary relative risk with 95% CI using the random-effects model of DerSimonian and Laird. ResultsData extracted from 3 trials, including 1,483 women with singleton pregnancy at term and cephalic presentation, were analyzed. Women who were randomized in the sexual intercourse group had similar incidence of spontaneous onset of labor compared with control subjects (0.82% vs 0.80%; relative risk 1.02, 95% CI 0.98–1.07). Clinical ImplicationSexual intercourse should not be restricted in low-risk term pregnancies. Further studies are needed to properly evaluate the impact of orgasm, penetration, condom use, frequency of intercourse and other factors on induction of labor at term. Strength & limitationsOur study has several strengths. The three included trials had low risk of allocation bias; intention-to-treat analysis was used; this is the first meta-analysis on this issue so far. Limitations mainly depend on the design of the included studies. Firstly, compliance to the protocol relied on self-reporting by patients; in addition, not all the features of sexual intercourse could be adequately assessed (orgasm, nipple stimulation, sexual positions, etc.). ConclusionIn women with singleton, cephalic, low-risk pregnancies, sexual intercourse at term does not significantly increase the incidence of spontaneous onset of labor.Carbone L, De Vivo V, Saccone G, et al. Sexual Intercourse for Induction of Spontaneous Onset of Labor: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. J Sex Med 2019;16:1787–1795.

Paleolithic diet during pregnancy—A potential beneficial effect on metabolic indices and birth weight

BackgroundPaleolithic diet has recently gained popularity due to its presumed health benefits. The favorable metabolic effects of this diet were assessed in non-pregnant population but its impact during pregnancy remains to be evaluated. Study designA retrospective cohort study comparing two groups. Group A comprised of women with singleton low-risk pregnancy adherent to paleolithic diet throughout gestation (n = 37). Group B comprised low risk pregnant women on a regular diet (n = 39). Women were excluded if they had low adherence to diet, started paleolithic diet during pregnancy, and had pre-gestational diabetes mellitus or other types of metabolic syndrome such as pre gestational hyperlipidemia, hypertension or BMI > 35. Blood indices such as Glucose challenge test scores, hemoglobin, ferritin, and TSH levels were compared. Other pregnancy factors such as maternal weight gain, rest days during gestation and pregnancy complications such as IUGR, GDM or preeclampsia were compared. Lastly, obstetrical outcomes such as mode of delivery and complications such as high-grade tears, as well as neonatal factors such as birth weight and pH were compared between the two groups. ResultsGeneral maternal characteristics such as age, BMI and parity were comparable between the two groups. Women who maintained a paleolithic diet had a significant decrease in glucose challenge test scores (95.8 mg/dL vs. 123.1 mg/dL, p < 0.01) and increase in hemoglobin levels (12.1 g/dL vs. 11.05 g/dL p < 0.01) and Ferritin (32.1 vs 21.3 mg/mL, p = 0.03) compared to women maintaining regular diet. Maternal pregnancy weight gain was also slightly decreased in group A (9.3Kg vs. 10.8 kg, p = 0.03). Birthweights were lower in group A (3098 g Vs.3275 g, p = 0.046) with no difference in adverse neonatal outcomes. We found no differences in other pregnancy complications or labor outcomes such as mode of delivery, shoulder dystocia or high grade perineal tears. ConclusionPaleolithic diet maintained during pregnancy may have a beneficial effect on the glucose tolerance. It also may increase iron stores and hemoglobin levels. Neonates of women maintaining paleolithic diet are slightly lighter but appropriate for gestational age with no difference in neonatal outcomes.

Reference ranges for left, right and interventricular septum indices at 20 to 36+6 weeks of gestation derived using spectral myocardial tissue Doppler on Voluson ultrasound machines.

To establish reference range values for peak myocardial tissue Doppler velocity (MTD) and myocardial performance index (MPI) of the left ventricle (LV), the right ventricle (RV), and the interventricular septum (IVS) at 20 to 36+6 weeks of gestation using spectral tissue Doppler. This cross-sectional study was conducted among 360 lowrisk singleton pregnancies. MTD during systole (S'), and early (E') and late diastole (A'), and MPI' were assessed by placing sample volume at the basal segment of the LV free wall, the RV free wall, and the IVS, respectively. Polynomial regression was used to obtain the best-fit curves for MTD and MPI' measurements as a function of gestational age (GA), and adjustments were made using the determination coefficient (R2). Intra- and inter-observer reproducibility was evaluated using the concordance correlation coefficient (CCC). All MTD velocities (cm/s) progressively increased with advancing GA (p<0.0001). Mean LV MTD values were 4.19 to 6.86 for S', 3.52 to 7.22 for E', and 6.85 to 9.19 for A'; mean RV MTD were 4.85 to 7.97 for S', 4.49 to 8.66 for E', and 8.44 to 11.20 for A'; and mean IVS MTD values were 3.75 to 5.78 for S', 3.34 to 5.79 for E', and 5.88 to 7.98 for A'. LV MPI', RV MPI', and IVS MPI' did not significantly change with advancing GA. The CCC values for MTD were predominantly greater than 0.70, while those for MPI' were <0.70. Reference values for the fetal MTD and MPI' of RV, LV and IVS using tissue Doppler between 20 and 36+6 weeks of gestation were described.

Are women in Singapore gaining weight appropriately during pregnancy: a prospective cohort study

BackgroundWe aimed to study gestational weight gain (GWG) in a Singaporean population and compare it with Institute of Medicine (IOM) 2009 GWG guidelines.MethodsNine hundred twenty-six women with low-risk singleton pregnancy were enrolled in a prospective cohort study from 2010 to 2014 in a Singapore tertiary maternity hospital. Seven hundred twenty-four patients had maternal weight information till term pregnancy and were included in analysis. Participants were categorized according to their first antenatal visit body mass index (BMI) as underweight, normal weight, overweight and obese. Total GWG for each BMI group was calculated. Multivariate logistic regression was performed to determine the predictors of total GWG above and below IOM guidelines.ResultsObese women had a mean total GWG (9.1 kg) that exceeded the upper limit IOM guidelines (9 kg). In multivariate analysis of predictors of total GWG above IOM guidelines, being overweight (adjusted OR: 3.91 [95% CI, 2.60–5.88]; p < .0001) and obese (adjusted OR: 4.78 [95% CI, 2.80, 8.15]; p < .0001) significantly increased the risks of gaining weight above IOM guidelines during pregnancy, compared to being normal weight.ConclusionsOverweight and obesity are independent significant risk factors for gaining excessive gestational weight. Appropriate weight management for overweight and obese Singaporean women prior to and during pregnancy is important.

Reference ranges for the left ventricle modified myocardial performance index, respective time periods, and atrioventricular peak velocities between 20 and 36 + 6 weeks of gestation

Objective: To establish reference ranges for the fetal left ventricle (LV) modified myocardial performance index (Mod-MPI), respective time periods, and right and left atrioventricular peak velocities between 20 and 36 + 6 weeks of gestation.Methods: This cross-sectional study evaluated 360 low-risk singleton pregnancies between 20 and 36 + 6 weeks of gestation. The LV Mod-MPI was calculated as (isovolumetric contraction time + isovolumetric relaxation time)/ejection time. Polynomial regression was used to obtain the best-fit using Mod-MPI and atrioventricular peak velocity measurements and gestational age (GA) with adjustments using the coefficient of determination (R2). The intra- and interobserver reliability was evaluated using the concordance correlation coefficient (CCC).Results: LV Mod-MPI (R2 = 0.026, p = .002) and isovolumetric relaxation time (IRT) (R2 = 0.036, p < .001) significantly increased with advancing GA. Isovolumetric contraction time (ICT) and ejection time (ET) did not significantly change with GA. RV and LV E wave, A wave, and E/A ratio significantly increased with GA (p < .001). The mean of each parameter ranged as follows: LV Mod-MPI (0.44–0.47 s), IRT (0.041–0.045 s), ICT (0.032–0.034 s), ET (0.167–0.167 s), RV E (30.2–46.91 cm/s), RV A (47.1–60.7 cm/s), RV E/A (0.65–0.78 cm/s), LV E (27.0–41.4 cm/s), LV A (43.2–53.8 cm/s), and LV E/A (0.63–0.78 cm/s). Only LV A wave measurements demonstrated an intraobserver CCC >0.80. The remaining intra- and interobserver reproducibility parameters demonstrated lower CCC.Conclusions: Reference values were replicated for the fetal LV Mod-MPI and LV and RV transvalvular peak velocities between 20 and 36 + 6 weeks of gestation.

Prediction of ischemic placental diseases during the first trimester combined test period: a retrospective cohort of low-risk pregnancies in search of the link between parity and disease

Objective: To assess the predictive power of a multifactorial model established on maternal characteristics, placenta-associated plasma protein A (PAPPA), and the mean uterine artery pulsatility index (Ut A PI) levels for the development of ischemic placental diseases (IPD) during the first-trimester combined test (FTCT) period and to evaluate the strength of some generally accepted clinical risk factors.Method: The studied data were obtained from a retrospective cohort of low-risk singleton pregnancies in the FTCT between 1 August 2016 and 1 December 2017. After routine 11–13-week examinations for FTCT, the Ut A PI was measured and stored electronically. The PAPPA multiple of median (MoM) was obtained as a routine component of aneuploidy screening.Results: A sample of 2493 pregnancies with clearly documented outcomes was studied. Early-onset preeclampsia, late-onset preeclampsia and fetal growth restriction (FGR) were observed in 9 (0.36%), 27 (1.08%), and 41 (1.64%) cases, respectively. With optimum cut-off levels of 0.69 for PAPPA MoM and 2.05 for mean Ut A PI and a false positive rate of 4.9%, IPD cases could be predicted with 83.3% sensitivity and 73.7% specificity. Nulliparity, previous abortion in nulliparous women and first pregnancy from second marriage were not independent risk factors. Maternal age, an interval from the last delivery longer than 6 years, and body mass index were found to be independent risk factors.Conclusion: The IPD showed some common and distinct clinical, laboratory and Doppler findings during the FTCT and were predictable with the help of multifactorial analysis. Some widely accepted risk factors could be affected by various confounders. Because of the increased IPD frequencies, parous women with a time interval from the last delivery of 6 years or longer should be screened as a high-risk group for placental dysfunction-related diseases.

Nomograms of Fetal Cardiac Dimensions at 18–41 Weeks of Gestation

Objective: There is a need for standardized reference values for cardiac dimensions in prenatal life. The objective of the present study was to construct nomograms for fetal cardiac dimensions using a well-defined echocardiographic methodology in a low-risk population. Methods: This is a prospective cohort study including 602 low-risk singleton pregnancies undergoing a standardized fetal echocardiography to accurately assess fetal cardiac, ventricular, and atrial dimensions. Parametric regressions were tested to model each measurement against gestational age from 18 to 41 weeks of gestation. Results: Nomograms were constructed for fetal cardiac dimensions (transverse and longitudinal diameters and areas) of the whole heart, atria, and ventricles, as well as myocardial wall thicknesses. All dimensions showed a progressive increase with gestational age. The best model for most parameters was a second-degree linear polynomial. Fetal cardiac, ventricular, and atrial diameters and areas were successfully obtained in 98.6% of the fetuses, while myocardial wall thicknesses could be obtained in 96.5% of the population. The results showed excellent interobserver and intraobserver reproducibility (intraclass correlation coefficient, ICC > 0.811 and ICC > 0.957, respectively). Conclusions: We provide standardized and comprehensively evaluated reference values for fetal cardiac morphometric parameters across gestation in a low-risk population. These no mograms would enable the early identification of different patterns of fetal cardiac remodeling.

Creatine and pregnancy outcomes, a prospective cohort study in low-risk pregnant women: study protocol

IntroductionThe creatine kinase circuit is central to the regulation of high-energy phosphate metabolism and the maintenance of cellular energy turnover. This circuit is fuelled by creatine, an amino acid derivative...

Maternal and perinatal outcomes after elective induction of labor at 39 weeks in uncomplicated singleton pregnancy: a meta-analysis.

The rate of maternal and perinatal complications increases after 39 weeks' gestation in both unselected and complicated pregnancies. The aim of this study was to synthesize quantitatively the available evidence on the effect of elective induction of labor at 39 weeks on the risk of Cesarean section, and on maternal and perinatal outcomes. PubMed, US Registry of Clinical Trials, SCOPUS and CENTRAL databases were searched from inception to August 2018. Additionally, the references of retrieved articles were searched. Eligible studies were randomized controlled trials of singleton uncomplicated pregnancies in which participants were randomized between 39 + 0 and 39 + 6 gestational weeks to either induction of labor or expectant management. The risk of bias of individual studies was assessed using the Cochrane Risk of Bias Tool. The overall quality of evidence was assessed according to the GRADE guideline. Primary outcomes included Cesarean section, maternal death and admission to the neonatal intensive care unit (NICU). Secondary outcomes included operative delivery, Grade-3/4 perineal laceration, postpartum hemorrhage, maternal infection, hypertensive disease of pregnancy, maternal thrombotic events, length of maternal hospital stay, neonatal death, need for neonatal respiratory support, cerebral palsy, length of stay in NICU and length of neonatal hospital stay. Pooled risk ratios (RRs) were calculated using random-effects models. The meta-analysis included five studies (7261 cases). Induction of labor was associated with a decreased risk for Cesarean section (moderate quality of evidence; RR 0.86 (95% CI, 0.78-0.94); I2 = 0.1%), maternal hypertension (moderate quality of evidence; RR 0.65 (95% CI, 0.57-0.75); I2 = 0%) and neonatal respiratory support (moderate quality of evidence; RR 0.73 (95% CI, 0.58-0.95); I2 = 0%). Neonates born after induction weighed, on average, 81 g (95% CI, 63-100 g) less than those born after expectant management. No significant effects were found for the other outcomes with the available data. The main limitation of our analysis was that the majority of data were derived from a single large study. A second limitation arose from the open-label design of the studies, which may theoretically have affected the readiness of the attending clinician to resort to Cesarean section. Elective induction of labor in uncomplicated singleton pregnancy at 39 weeks' gestation is not associated with maternal or perinatal complications and may reduce the need for Cesarean section, risk of hypertensive disease of pregnancy and need for neonatal respiratory support. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Antenatal Anxiety: Prevalence and Patterns in a Routine Obstetric Population

Expectant mothers may appear anxious even during healthy pregnancies. Unfortunately, little is known about antenatal anxiety, and affected women may remain undetected and untreated. This study aimed to examine the prevalence, incidence, course and associations of high state anxiety in routine obstetric care. This was an observational prospective cohort study at a large maternity unit. Obstetric outpatients with low-risk singleton pregnancies were recruited during first trimester consultations. Participants provided sociodemographic data and completed the State-Trait Anxiety Inventory (STAI) and Edinburgh Postnatal Depression Scale. The STAI was re-administered at each subsequent trimester. Prevalence and incidence of high state anxiety among 634 completers were 29.5% (95% CI 25.6%-33.6%) and 13.9% (95% CI 9.9%-18.0%), respectively. Anxiety was persistent in 17.0% (95% CI 14.3%-20.2%) and transient in 26.3% (95% CI 23.1%-29.9%). Only persistently anxious participants had high mean second trimester state anxiety scores. Odds for anxiety of greater persistence increased by 29% (95% CI 24%-35%) per 1-point increase in first trimester depression scores, and decreased by 36% (95% CI 7%-56%) with tertiary education. Antenatal anxiety symptoms are common even in normal pregnancies, especially among women with depression and lower education. Our study indicates value in exploring diagnostic criteria and quantitative measures for antenatal anxiety.

OP19.01: Diagnostic performance of ultrasound for the prediction of late smallness‐for‐gestational age: a systematic review and meta‐analysis

To establish the diagnostic performance of ultrasound (US) screening for the prediction of late smallness-for-gestational age (SGA). Prospective and retrospective cohort studies in low-risk or non-selected singleton pregnancies with screening ultrasound performed at >32 weeks of gestation. Birthweight (BW) below the 10th centile was considered the reference standard, while abdominal circumference (AC) and estimated fetal weight (EFW) below the 10th centile were considered index tests. A hierarchical summary receiver–operating characteristics curve was constructed. A Wald-type test was used to compare both index tests. Quantitative synthesis of data was performed using fixed and random effects models. A meta-regression between gestational age at US scan and the pooled estimates of EFW was also performed. A total of 20 studies and 262,419 scans were included in this meta-analysis. Pooled data on the performance of AC <10th centile for the prediction of BW <10th centile showed a 64% Sensitivity (Se) and 97% specificity (Sp). The pooled Se and Sp of EFW <10th centile was 46% and 95%, respectively. Performance for AC was significantly better than EFW (Wald-type test: p<0.001). Meta-regression analysis showed a significant increase in EFW sensitivity when US evaluation was performed later in pregnancy (p=0.018). Performance of third trimester ultrasound screening for late-SGA is significantly better when based on AC and conducted near 37 weeks of gestation. Supporting information can be found in the online version of this abstract Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Z Score Reference Ranges of Fetal Cardiothoracic Diameter Ratio.

This study aims to establish the z score reference ranges of cardiothoracic diameter ratio (CTR) of normal fetuses from 14 to 40 weeks' gestation. A cross-sectional study was conducted on low-risk singleton pregnancies with healthy fetuses. The CTR was performed using simple 2-dimensional sonography on the typical fetal 4-chamber view. The reference ranges were constructed according to gestational age (GA), biparietal diameter (BPD), and head circumference (HC) as independent variables based on the best-fit models, both mean and standard deviation (SD). A total of 683 fetuses were measured for CTR. The best-fit equations for the mean and SD as a function of GA, BPD, and HC are as follows: (1) CTR = 0.365 + 0.004 × GA in weeks (SD = 0.031 + 0.001 × GA); (2) CTR = 0.373 + 0.014 × BPD in cm (SD = 0.034 + 0.004 × BPD); and (3) CTR = 0.373 + 0.004 × HC in cm (SD = 0.032 + 0.001 × HC). The CTR was slightly increased with advanced GA, BPD, and HC. Complete nomograms with z score reference ranges of CTR were established throughout pregnancy. These nomograms may be useful to detect cardiac abnormalities.

Can the difference of Doppler indexes at the different points of the umbilical artery predict to the umbilical cord length?

Background: The aim of the study is to investigate whether the Doppler indexes which measured at different points of the umbilical cord (UC) are related to the cord length.Materials and methods: In this prospective study, umbilical artery (UA) Doppler indexes were measured at the fetal and placental insertion, free loop (FL) and intra-abdominal (IA) portion at 37–42 weeks of gestation in low-risk singleton pregnancies. After birth, the UC was measured. The difference of Doppler indexes of different points was evaluated by nonparametric Kruskal–Wallis test or analysis of variance (ANOVA) test and significant values have been adjusted by the Bonferroni correction for multiply tests. The correlation of between UC length and change of Doppler indexes which measured at different points of the UC was evaluated using Spearman’s rank correlation test.Results: The data of 74 participants were analyzed in this study. Mean UC length was 58 cm (min: 38 cm and max: 84 cm). There was no difference between characteristics of two groups that UC length <58 cm and ≥58 cm and different percentiles. UA systole/diastole (S/D) rate, resistance index (RI), and pulsatility index (PI) were higher at the IA portion than other measurement points (p = .003, <.001, and <.001, respectively). The mean differences (delta values) of UA blood velocity between the fetal and placental ends (PEs) were correlated UC length (c = 0.32, p = .04).Conclusions: The differences of UA blood velocities between the fetal and PEs may be a useful marker for UC length prediction during antenatal period.

Maternal exercise, season and sex modify the daily fetal heart rate rhythm.

The knowledge on biological rhythms is rapidly expanding. We aimed to define the longitudinal development of the daily (24-hour) fetal heart rate rhythm in an unrestricted, out-of-hospital setting and to examine the effects of maternal physical activity, season and fetal sex. We recruited 48 women with low-risk singleton pregnancies. Using a portable monitor for continuous fetal electrocardiography, fetal heart rate recordings were obtained around gestational weeks 24, 28, 32 and 36. Daily rhythms in fetal heart rate and fetal heart rate variation were detected by cosinor analysis; developmental trends were calculated by population-mean cosinor and multilevel analysis. For the fetal heart rate and fetal heart rate variation, a significant daily rhythm was present in 122/123 (99.2%) and 116/121 (95.9%) of the individual recordings respectively. The rhythms were best described by combining cosine waves with periods of 24 and 8hours. With increasing gestational age, the magnitude of the fetal heart rate rhythm increased, and the peak of the fetal heart rate variation rhythm shifted from a mean of 14:25 (24weeks) to 20:52 (36weeks). With advancing gestation, the rhythm-adjusted mean value of the fetal heart rate decreased linearly in females (P<.001) and nonlinearly in males (quadratic function, P=.001). At 32 and 36weeks, interindividual rhythm diversity was found in male fetuses during higher maternal physical activity and during the summer season. The dynamic development of the daily fetal heart rate rhythm during the second half of pregnancy is modified by fetal sex, maternal physical activity and season.

Pre-pregnancy fast food and fruit intake is associated with time to pregnancy.

STUDY QUESTION Is preconception dietary intake associated with reduced fecundity as measured by a longer time to pregnancy (TTP)? SUMMARY ANSWER Lower intake of fruit and higher intake of fast food in the preconception period were both associated with a longer TTP. WHAT IS KNOWN ALREADY Several lifestyle factors, such as smoking and obesity, have consistently been associated with a longer TTP or infertility, but the role of preconception diet in women remains poorly studied. Healthier foods or dietary patterns have been associated with improved fertility, however, these studies focused on women already diagnosed with or receiving treatments for infertility, rather than in the general population. STUDY DESIGN, SIZE, DURATION This was a multi-center pregnancy-based cohort study of 5628 nulliparous women with low-risk singleton pregnancies who participated in the Screening for Pregnancy Endpoints (SCOPE) study. PARTICIPANTS/MATERIALS, SETTING, METHODS A total of 5598 women were included. Data on retrospectively reported TTP and preconception dietary intake were collected during the first antenatal study visit (14-16 weeks' gestation). Dietary information for the 1 month prior to conception was obtained from food frequency questions for fruit, green leafy vegetables, fish and fast foods, by a research midwife. Use of any fertility treatments associated with the current pregnancy was documented (yes, n = 340, no, n = 5258). Accelerated failure time models with log normal distribution were conducted to estimate time ratios (TR) and 95% CIs. The impact of differences in dietary intake on infertility (TTP >12 months) was compared using a generalized linear model (Poisson distribution) with robust variance estimates, with resulting relative risks (RR) and 95% CIs. All analyses were controlled for a range of maternal and paternal confounders. Sensitivity analyses were conducted to explore potential biases common to TTP studies. MAIN RESULTS AND THE ROLE OF CHANCE Lower intakes of fruit and higher intakes of fast food were both associated with modest increases in TTP and infertility. Absolute differences between the lowest and highest categories of intake for fruit and fast food were in the order of 0.6-0.9 months for TTP and 4-8% for infertility. Compared with women who consumed fruit ≥3 times/day, the adjusted effects of consuming fruit ≥1- 0- 0-<2 times/week, or no fast food, corresponded to an 18, 34 and 41% reduced risk of infertility (Ptrend <0.001). Pre-pregnancy intake of green leafy vegetables or fish were not associated with TTP or infertility. Estimates remained stable across a range of sensitivity analyses. LIMITATIONS, REASONS FOR CAUTION Collection of dietary data relied on retrospective recall and evaluated a limited range of foods. Paternal dietary data was not collected and the potential for residual confounding cannot be eliminated. Compared to prospective TTP studies, retrospective TTP studies are prone to a number of potential sources of bias. WIDER IMPLICATIONS OF THE FINDINGS These findings underscore the importance of considering preconception diet for fecundity outcomes and preconception guidance. Further research is needed assessing a broader range of foods and food groups in the preconception period. STUDY FUNDING/COMPETING INTEREST(S) The SCOPE database is provided and maintained by MedSciNet AB (http://medscinet.com). The Australian SCOPE study was funded by the Premier's Science and Research Fund, South Australian Government (http://www.dfeest.sa.gov.au/science-research/premiers-research-and-industry-fund). The New Zealand SCOPE study was funded by the New Enterprise Research Fund, Foundation for Research Science and Technology; Health Research Council (04/198); Evelyn Bond Fund, Auckland District Health Board Charitable Trust. The Irish SCOPE study was funded by the Health Research Board of Ireland (CSA/2007/2; http://www.hrb.ie). The UK SCOPE study was funded by National Health Service NEAT Grant (Neat Grant FSD025), Biotechnology and Biological Sciences Research council (www.bbsrc.ac.uk/funding; GT084) and University of Manchester Proof of Concept Funding (University of Manchester); Guy's and St. Thomas' Charity (King's College London) and Tommy's charity (http://www.tommys.org/; King's College London and University of Manchester); and Cerebra UK (www.cerebra.org.uk; University of Leeds). L.E.G. is supported by an Australian National Health and Medical Research Council (NHMRC) Early Career Fellowship (ID 1070421). L.J.M. is supported by a SACVRDP Fellowship; a program collaboratively funded by the National Heart Foundation, the South Australian Department of Health and the South Australian Health and Medical Research Institute. L.C.K. is supported by a Science Foundation Ireland Program Grant for INFANT (12/RC/2272). C.T.R. was supported by a National Health and Medical Research Council (NHMRC) Senior Research Fellowship (GNT1020749). There are no conflicts of interest to declare. TRIAL REGISTRATION NUMBER Not applicable.

Association between amniotic fluid evaluation and fetal biometry: a prospective French \u201cFlash\u201d study

We aimed to study the association between three different methods of assessing the amount of amniotic fluid (subjective method (SM), deepest vertical pocket (DVP) and amniotic fluid index (AFI)) and estimated fetal weight (EFW) (in percentile or Z-score) after adjustment on maternal-fetal parameters. We performed a nationwide cross-sectional study through the French network of obstetric sonographers using the “flash” study method and including low-risk singleton pregnancies from 18–40 weeks. Crude and adjusted odds ratio were computed after stratification upon 2nd and 3rd trimester of pregnancy. 1667 ultrasound scans performed by 65 operators were included. Only Z-score of EFW was significantly associated with SM in both trimesters. For DVP and AFI, Z-score of EFW and male fetal gender was significantly associated with them in 2nd trimester. In the 3rd trimester, both Z-score of EFW and large (LGA) or small for gestational age (SGA) fetus were significantly associated with AFI. and DVP. Overweight woman and class I obesity women were also significantly associated with DVP modification. In conclusion, all three methods of amniotic fluid evaluation are significantly associated to estimated fetal weight. DVP and AFI appeared equivalent except that maternal-fetal factors seemed to have a higher impact in DVP than AFI.

Do Maternal Sociodemographic Factors Explain Race/Ethnic Differences in Neonatal Anthropometry in Low Risk Women? [14N

INTRODUCTION: Racial/ethnic differences in birthweight exist. It is unclear to what extent these differences are due to correlates of social disadvantage. Our objective was to evaluate whether relationships between maternal race/ethnicity and neonatal anthropometry varied by maternal socio-demographic characteristics in a cohort of healthy, low-risk women. METHODS: In a prospective cohort of 1,645 low-risk singleton pregnancies included in the NICHD Fetal Growth Studies (2010-2013), neonatal anthropometry was measured by trained personnel using a standard protocol. Sociodemographic characteristics were ascertained by interview and included full-time employment/student status (yes/no), marital status, health insurance source (private/managed vs Medicaid/other), income, and education. Separate generalized linear models were used to test the effect of race/ethnicity and the combined effect of race/ethnicity and sociodemographic characteristics (with two-way interaction terms) on neonatal anthropometry adjusting for days from birth (except birthweight) infant sex, and maternal characteristics: age, height, pre-gravid weight, parity, and the other sociodemographic factors. RESULTS: Mean birthweight, and neonatal weight, length, head circumference and abdominal circumference at examination differed significantly by race (p&lt;0.001 for all comparisons). No statistically significant interactions occurred between race/ethnicity and full-time employment/student status, marital status, insurance, or education in association with birthweight, neonatal weight, length, or head or abdominal circumference at examination. The interaction of income with race/ethnicity was marginally significant for abdominal circumference (p=0.027). There were no significant interactions of income with other neonatal parameters and the observed significance may have occurred by chance (1 of 25 models). CONCLUSION: Racial/ethnic differences in neonatal anthropometry were not explained by sociodemographic factors in low-risk women.

Sex differences in umbilical artery Doppler indices: a longitudinal study

BackgroundSexual dimorphism in placental size and function has been described. Whether this influences the clinically important umbilical artery (UA) waveform remains controversial, although a few cross-sectional studies have shown sex differences in UA pulsatility index (PI). Therefore, we tested whether fetal sex influences the UA Doppler indices during the entire second half of pregnancy and aimed to establish sex-specific reference ranges for UA Doppler indices if needed.MethodsOur main objective was to investigate gestational age-associated changes in UA Doppler indices during the second half of pregnancy and compare the values between male and female fetuses. This was a prospective longitudinal study in women with singleton low-risk pregnancies during 19–40 weeks of gestation. UA Doppler indices were serially obtained at a 4-weekly interval from a free loop of the umbilical cord using color-directed pulsed-wave Doppler ultrasonography. Sex-specific reference intervals were calculated for the fetal heart rate (HR), UA PI, resistance index (RI), and systolic/diastolic ratio (S/D) using multilevel modeling.ResultsComplete data from 294 pregnancies (a total of 1261 observations from 152 male and 142 female fetuses) were available for statistical analysis, and sex-specific reference ranges for the UA Doppler indices and fetal HR were established for the last half of pregnancy. UA Doppler indices were significantly associated with gestational age (P < 0.0001) and fetal HR (P < 0.0001). Female fetuses had 2–8% higher values for UA Doppler indices than male fetuses during gestational weeks 20+0–36+6 (P < 0.05), but not later. Female fetuses had higher HR from gestational week 26+0 until term (P < 0.05).ConclusionsWe have determined gestational age-dependent sex differences in UA Doppler indices and fetal HR during the second half of pregnancy, and correspondingly established new sex-specific reference ranges intended for refining diagnostics and monitoring individual pregnancies.