Introduction: In this study, we aimed at quantifying placental concentrations of 22 chemical elements in small fetuses (SGA) as compared with normally grown fetuses (AGA), and to assess the relationship with Doppler markers of placental function. Methods: Prospective cohort study, including 71 SGA fetuses (estimated fetal weight < 10th percentile) and 96 AGA fetuses (estimated fetal weight > 10th percentile), recruited in the third trimester of gestation. The placental concentration of 22 chemical elements was determined by inductively coupled plasma optical emission spectrophotometer (ICP-OES, ICAP 6500 Duo Thermo): aluminum (Al), beryllium (Be), bismuth (Bi), calcium (Ca), cadmium (Cd), cobalt (Co), chrome (Cr), copper (Cu), magnesium (Mg), manganese (Mn), molybdenum (Mo), nickel (Ni), phosphorus (P), lead (Pb), rubidium (Rb), sulfur (S), strontium (Sr), titanium (Ti), thallium (Tl), antimony (Sb), selenium (Se), and zinc (Zn). Placental function was assessed by measuring the following fetal-maternal parameters: Uterine artery Pulsatility Index (UtA PI), Umbilical artery Pulsatility Index (UA PI) and Middle Cerebral artery Pulsatility Index (MCA PI). The association between the chemical elements concentration and study group and the association with Doppler measures were evaluated. Results: SGA was associated with significantly (p < 0.05) lower concentrations of Al (AGA 21.14 vs SGA 0.51 mg/kg), Cr (AGA 0.17 vs SGA 0.12 mg/kg), Cu (AGA 0.89 vs SGA 0.81 mg/kg), Mg (AGA 0.007 vs SGA 0.006 g/100g), Mn (AGA 0.60 vs SGA 0.47 mg/kg), Rb (AGA 1.68 vs SGA 1.47 mg/kg), Se (AGA 0.02 vs SGA 0.01 mg/kg), Ti (AGA 0.75 vs SGA 0.05 mg/kg) and Zn (AGA 9.04 vs SGA 8.22 mg/kg). Lower placental concentrations of Al, Cr, Mn, Se, Ti were associated with abnormal UtA, UA and MCA Doppler. Discussion: Lower placental concentrations of Al, Cr, Cu, Mn, Rb, Se, Ti and Zn are associated with SGA fetuses and abnormal fetal-maternal Doppler results. Additional studies are required to further understand how chemical elements affect fetal growth and potentially find strategies to prevent SGA.

To assess the mental well-being of pregnant and postpartum women during the COVID-19 pandemic. A cross-sectional, web-based international survey was carried out between May 15 and October 15, 2020. The survey was available in English, Spanish, Italian and Russian and promoted through social media and health care professionals. The questions evaluated sociodemographic characteristics, medical and obstetric history, COVID-19 symptoms and infection. The World Health Organization well-being index (WHO-5) was used to assess mental health status. Pregnant and postpartum women up to 12 months postpartum who were older than 18 years of age were eligible. Women were classified as having a low (WHO-5 ≦52) or high (WHO-5 > 52) mental well-being. Multivariate linear regression was used to identify factors associated with low mental well-being. A total of 4221 patients provided valid surveys for analysis (3324 pregnant and 897 postpartum women). The mean (±SD) WHO-5 scores for pregnant and postpartum women were 54.3 ± 20.3 and 54.7 ± 21, respectively. Low mental well-being was observed in 42% and 40% of pregnant and postpartum women respectively. Factors associated with low mental well-being included residence in a South American country (p < 0.001), being a single mother (p < 0.001), smoking (p < 0.001), having a respiratory or a psychiatric disorder (p = 0.02 and 0.03 respectively), multiparity (p < 0.001), the presence of symptoms like difficulty breathing (p = 0.02), diarrhoea (p = 0.04) and muscle pain (p < 0.001), and the pandemic period (p < 0.001). The second and third trimesters of pregnancy and the postpartum period were associated with higher mental well-being compared to the first trimester (p < 0.001). A history of hospital admission, pneumonia, or intensive care unit admission due to COVID-19 infection was not associated with worse mental well-being score. Sociodemographic characteristics, and not the SARS-COV-2 infection, were the determinants of mental well-being among pregnant and postpartum women during the COVID-19 pandemic.

To determine the effect of SARS-CoV-2 pandemic on maternal mental well-being during pregnancy and its related factors. A multicentric, prospective, population-based study (n = 1,320) including pregnant women consecutively attended during SARS-CoV-2 pandemic in Barcelona, Spain (March-June 2020). SARS-CoV-2 antibodies were measured in all participants and nasopharyngeal RT-PCR was performed at delivery to assess SARS-CoV-2 infection status. In addition, a previous pre-pandemic cohort (n = 345), matched by baseline maternal characteristics with the pandemic cohort, was used for comparison. Maternal mental well-being was assessed using the validated World Health Organization Well-Being Index (WHO-5). Women were classified as having a low (WHO-5 £52) or high (WHO-5 > 52) mental well-being. In comparison with the pre-pandemic cohort, pregnant women attended during COVID-19 pandemic showed a worst WHO-5 well-being score (median pandemic cohort 56 [IQR 36-72] vs pre-pandemic 64 [IQR 52-76], p < 0.001), with a 42.8% of women presenting a low a mental well-being score vs 28% pre-pandemic (p < 0.001). At multivariate analysis, significant contribution to a low maternal mental well-being during COVID-19 pandemic were provided by the presence of a previous psychiatric disorder (OR 6.8; 95% CI 2.5-18.5, p < 0.001), being in the third trimester of pregnancy (OR 1.7; 95% CI 1.5-1.9, p < 0.001) or requiring hospital admission for COVID-19 (OR 6.8; 95% CI 1.5-18, p = 0.011). The infection for SARS-CoV-2, which affected 202 women (15.3%), was not associated with a lower mental well-being score. COVID-19 pandemic was associated with high rates of poor maternal mental well-being of pregnant women, particularly in those in the third trimester of pregnancy. However, not the infection of SARS-CoV-2 itself but other factors, such as previous psychiatric disorders, being at third trimester or hospital admission, were determinants for the lowest mental well-being condition.

To describe the impact of COVID-19 infection throughout gestation on pregnancy outcomes in a population-based study. A multicentric, prospective population-based study including pregnant women consecutively attended at first/second trimester or at delivery at three University hospitals in Barcelona, Spain, (March-June 2020). COVID-19 infection status was known by antibodies (IgG and IgM/IgA) measured in all participants and nasopharyngeal RT-PCR performed at delivery. The primary outcome was a composite score of pregnancy complications including miscarriage, pre-eclampsia, preterm delivery, perinatal death, and/or small-for-gestational age (SGA). Secondary outcomes were individual components of the primary outcome plus labour induction and Caesarean section. Outcomes were compared between COVID-19 positive vs. negative women, and also between positive symptomatic vs. positive asymptomatic women. Of 2,225 pregnant women, 317 (14.2%) were positive for COVID-19 antibodies (n = 314, 99.1%) and/or RT-PCR (n = 36, 11.4%). The primary outcome was similar in COVID-19 positive (20.8%) vs. negative (20%) women (p = 0.74). There were no differences between positive and negative women in the rate of miscarriage (1.4% vs 2.3%), pre-eclampsia (5.4% vs 3.8%), perinatal death (0.9% vs 0.6%), SGA (12.9% vs 12.8%), induction of labour (31.5% vs 32.1%) and Caesarean section (27.1% vs 24.6%); however, the rate of preterm delivery increased in infected women (9.1% vs 5.8%, p = 0.03), particularly for late-onset preterm birth (34-37wks) (6.6% vs 3.5%, p = 0.01). This risk increased even more considering women with symptomatic COVID-19, compared to non-infected (14% vs 5.8%, p < 0.001), and positive asymptomatic women (14% vs 6.9%, p = 0.02). This large population-based study of COVID-19 during pregnancy was able to capture a real picture of the infection throughout gestation. COVID-19 did not increase the risk of perinatal complications, with the exception of preterm delivery, particularly for symptomatic COVID-19 cases.

To describe the clinical presentation of COVID-19 infection throughout gestation in a population-based study. A multicentric, prospective population-based study including pregnant women consecutively attended at first/second trimester or at delivery at three University hospitals in Barcelona, Spain (March-June 2020). COVID-19 infection status was known by antibodies (IgG and IgM/IgA) measured in all participants and nasopharyngeal RT-PCR performed at delivery. In all participants, COVID-19 symptoms between mid-February 2020 and the time of testing for COVID-19 were recorded using a structured questionnaire. Of 2,225 pregnant women, 317 (14.2%) were positive for COVID-19 antibodies (n = 314, 99.1%) and/or RT-PCR (n = 36, 11.4%). The prevalence of the infection was similar between early (15.3%, 141/921) and late (13.5%, 176/1,304) pregnancy, whereas the clinical presentation was different. Women in the first/second trimester were mostly asymptomatic, compared to third trimester women (79% vs. 60%, p < 0.001), and the most frequent symptoms were loss of taste/smell (11%), fever (10%), dry cough (9%), and myalgia (6%); none of them were hospitalised for COVID-19. On the contrary, symptomatic women in late pregnancy presented a higher rate of dry cough (21%), fever (18%), and dyspnea (13%), and 15 (9%) required hospitalisation for COVID-19; 7 had a pneumonia (4%), of which 3 required intensive care unit admission, although mechanical ventilation was just needed for one of them. All women were discharged well and no maternal deaths were reported. This large population-based study based was able to capture a real picture of COVID-19 infection throughout gestation. The majority of infections were asymptomatic or mild, and the small proportion of severe cases were close to delivery.

Objectives: Nasopharyngeal microbiota has been implicated with respiratory infections; however, no previous evidence is reported during SARS-CoV-2 in pregnancy. The aim of this study was to characterise the nasopharyngeal microbiota in pregnant women with and without SARS-CoV-2 infection. Methods: Pregnant women from a multicentre prospective population-based cohort (March-June 2020 in Barcelona, Spain) in which the status of SARS-CoV-2 infection was known by a nasopharyngeal RT-PCR and antibodies in peripheral blood. DNA was extracted from nasopharyngeal swab samples, and the V3-V4 region of the 16S rRNA of bacteria was amplified using regions’ specific primers. Differential abundance of taxa was tested, alpha and beta diversity were evaluated. Results: Among 76 women, 38 were classified as positive and 38 for as negative for SARS-CoV-2 infection. All positive women were diagnosed by antibodies and 14 (37%) had also a positive RT-PCR. SARS-CoV-2 infection altered the overall composition of the nasopharyngeal microbiota (F=1.36, p = 0.001) with higher relative abundance of Tenericutes and Bacteroidetes phylum, as well as higher abundance of Prevotellaceae family. Infected women presented a different pattern of microbiota profiling due to beta diversity, and higher richness (Observed ASV<0.001) and evenness (Shannon index <0.001) at alpha diversity. These changes persisted after the acute infection revealed by a negative RT-PCR but positive antibodies, suggesting a long-lasting effect of SARS-CoV-2 in the nasopharyngeal microbiota. No significant differences were reported in mild vs. severe cases, suggesting a role of the SARS-CoV-2 infection itself but not on its severity. Conclusions: This is the first study on nasopharyngeal microbiota during pregnancy. SARS-CoV-2 infection altered the overall structure and diversity of the nasopharyngeal microbiota profiling and this effect seems to persist after the acute moment of the infection. OC15.04 Fetal cardiac remodelling after maternal SARS-CoV-2 infection during pregnancy

There is a paucity of data on COVID-19 in pregnancy. The proposed study is designed to provide critical data on the characteristics of the infection in pregnant women by means of a population-based in pregnant and non-pregnant women. The primary objectives are to describe the seroprevalence, clinical spectrum compared with non-pregnant women and perinatal outcomes of COVID-19 in pregnancy. A secondary objective is to evaluate the clinical presentation of COVID-19 with maternal gut microbiota patterns. The sample size was calculated assuming a 15% COVID-19 positive rate. Baseline characteristics, clinical symptoms for COVID-19, obstetrical and perinatal outcome will be collected. In all women, nasopharyngeal (NP) swabs will be obtained for SARS-CoV2 RT-PCR and serum (maternal peripheral blood and cord blood) for SARS-CoV2 IgM and IgG. Neonatal NP swabs and antibodies in cord blood will be evaluated in all SARS-CoV2+ and 1-to-1 matched controls. Rectal swabs in pregnant women SARS-CoV2+ and controls matched 1-to-1 will be used to study the microbiota in relation with clinical presentation. Final results will be available by the end of June 2020. This study will provide important population-based data on the clinical presentation and impact on perinatal outcomes of COVID-19.

To explore the pattern of cortical development in pregnancies complicated by pre-eclampsia (PE) with or without fetal growth restriction (FGR), as compared to uncomplicated pregnancies. Prospective observational study including pregnancies complicated by normotensive FGR (birth weight < 10th centile) (n=77), PE with normally grown fetuses (n=78), PE with FGR (n=77), and 128 uncomplicated pregnancies matched by gestational age at ultrasound. Detailed neurosonography with transabdominal and transvaginal approach was performed at 33±2 weeks including measurement of Insula, Sylvian fissure and Parieto-occipital, Cingulate and Calcarine sulci. All measurements were adjusted by biparietal diameter (BPD). As previously reported, FGR fetuses showed significant differences in cortical development with reduced Sylvian fissure and parieto-occipital sulcus depth together with larger Insula width. Interestingly, a similar pattern of reduced Sylvian fissures and larger Insula depth were observed in the PE group with normally grown fetuses (table 1). No significant differences could be demonstrated in cingulate and calcarine sulci depth through groups. Fetuses of pre-eclamptic mothers with or without FGR are associated with cortical development changes in intrauterine life, similarly to what has been previously described for FGR alone. 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.

To explore the performance of ultrasound and biochemical parameters for the prediction of adverse perinatal outcome (APO) in a cohort of suspected small-for-gestational-age (SGA) fetuses. Prospective observational study including pregnancies with an estimated fetal weight < 10thcentile. Fetoplacental ultrasound with Doppler parameters and maternal biomarkers (placental growth factor-PlGF- and soluble soluble fms-like tyrosine kinase-1-sFlt1-) were assessed in all women admitted for delivery. Logistic regression predictive models were developed for predicting APO defined as the occurrence of stillbirth, umbilical artery cord blood pH < 7.10 or base excess >-12, 5-min Apgar score < 7 or emergency operative delivery for fetal distress. Theperformance of each parameter was determined by receiver operating characteristic curve (AUC) and detection rate (DR) was calculated at 10% of false positive rate (FPR). Among 314 suspected SGA fetuses, 66 (21%) had an APO. Fetuses with APO had significantly higher values of mean umbilical artery pulsatility index (PI) z-scores (1.49 vs. 0.41, p < 0.001), ductus venosus PI z-scores (1.22 vs. 0.3, p = 0.01), sFlt1 MoM (1.98 vs. 0.9, p < 0.001), sFlt1/PlGF ratio MoM (13.8 vs. 2.48, p < 0.001), whereas middle cerebral artery PI z-scores (-1.17 vs. -0.15, p < 0.001), cerebroplacental ratio PI z-scores (-1.73 vs. -0.71, p < 0.001), and PlGF MoM (0.16 vs. 0.36, p < 0.001) were significantly lower. At multivariate analysis, the prediction of APO was best achieved by lower cerebroplacental ratio PI z-score (DR 42%, AUC 0.702 [0.628-0.777]), and higher sFlt1/PlGF ratio (DR 50%, AUC 0.734 [0.661-0.806]). The combined model did not improve the prediction (DR 49%, p = 0.248). The use of cerebroplacental ratio and/or the maternal angiogenic factors before delivery could provide a clinically useful prediction of APO in suspected SGA fetuses. Further studies are needed to explore the role of these parameters earlier during gestation. 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.