Objectives: The aim of this study was to explore the associations of abdominal muscles thickness and inter-recti distance (IRD) at late pregnancy with birth-related outcomes and umbilical cord blood (CB) gas values. Design: cross-sectional study. Setting: Sport and Health University Research Institute Sample: One hundred and fifty-two pregnant women. Main outcome measures: The thickness of the abdominal muscles (transverse abdominis [TrA], internal [IO] and external obliques [EO]) and the IRD were measured by ultrasound at the 34th gestational week. Birth outcomes were collected from obstetric medical records. Umbilical CB gas concentrations were assessed after birth using a blood analyzer. Results: Greater TrA and IO thickness were associated with a higher venous CB PO2 value, both at muscular rest (respectively, p<0.01 and p<0.05) and during activation (both p<0.05). A greater activated TrA thickness was associated with a higher venous CB oxygen saturation (p<0.05). EO thickness at rest was positively related to arterial CB pH (p<0.05), and during activation to the 1-minute Apgar test (p<0.05). A greater IRD was associated with higher arterial (at rest p<0.01; during crunches p<0.05) and venous CB (at rest, p<0.05) PCO2 values, and with lower arterial CB PO2 (p<0.05), arterial CB oxygen saturation (at rest, p<0.05; during crunches p<0.01), and venous CB oxygen saturation (during crunches, p<0.05, and lower venous pH (p<0.05). Conclusion: Greater abdominal muscle thicknesses and a smaller IRD at late pregnancy are related to better umbilical CB gas values at birth. ClinicalTrials.gov Identifier: NCT02582567

Objective: To determine the presence of anti-SARS-CoV-2 antibodies in colostrum and mature milk in women who had SARS-CoV-2 infection during pregnancy or at delivery; to investigate the correlation between anti-SARS-CoV-2 antibodies in milk with antibody in maternal blood, severity of infection and time-interval from active illness; and to evaluate immunoglobulin evolution from colostrum to mature milk. Design: prospective cohort-study Setting: six hospitals in Spain and Hong-Kong. Sample: pregnant women with confirmed SARS-CoV-2 infection during pregnancy or at delivery. Methods: Colostrum and mature milk were collected by manual expression with strict contact precautions. Colostrum samples were tested with rRT-PCR-SARS-CoV-2 and both, maternal milk and serum were tested against SARS-CoV-2 specific immunoglobulin M, A and G reactive to receptor binding domain of SARS-CoV-2 spike protein-1. Results: All rRT-PCR-SARS-CoV-2 tested negative. IgA and IgG were present in 111/135 (82.2%) and 2/135 (1.5%) colostrum samples and 27/81 (33.3%) and 0/81 mature milk samples, respectively. Concentrations of immunoglobulins were not associated with the timing of infection but women with SARS-CoV-2 pneumonia had higher levels of IgA and IgG in colostrum than those who were asymptomatic or had mild symptoms. Conclusion: No SARS-CoV-2 virus was found in human milk, however, high levels of antibodies were found in colostrum, specially IgA, irrespective of the time of infection. All women should be encouraged to breastfeed, undertaking strict contact precautions when there is active disease. Funding: Spanish Government grant (Instituto de Salud Carlos III: COV20/00188). Synlab Diagnostics’ Globales (Madrid, Spain). Perkin Elmer.