Cytomegalovirus (CMV) is the most frequent cause of congenital infection all over the world. Its prevalence ranges from 0.2 to 2.2%. Transmission from children to their pregnant mothers is a well-known risk factor, particularly if they attend a childcare centre. This study aims to compare the prevalence of CMV congenital infection (CMV_CI) in Portugal (Lisbon) between two studies, performed respectively in 2019 and 2020. In the 2019 study, performed in two hospitals, we found a 0.67% CMV_CI prevalence, using a pool strategy previously tested with saliva samples. In the 2020 study, using the same pool approach in four hospitals (the previous and two additional), and based on 1277 samples, the prevalence was 0.078%. Conclusion:The close temporal coincidence with COVID-19 lockdown suggests that these measures may have had a significant impact on this reduction, although other explanations cannot be ruled-out. What is Known:• Cytomegalovirus is the leading cause of congenital infection.• Behavioural measures decrease cytomegalovirus seroconversion in pregnant women.

Resumo Com o advento do surfactante, dos corticosteróides prénatais e dos avanços na tecnologia, a sobrevida dos recém-nascidos de extremo baixo peso tem melhorado dramaticamente. As taxas de displasia broncopulmonar (DBP) variam amplamente entre unidades, e vários estudos, avaliando resultados de múltiplas intervenções, têm mostrado alguma melhoria na prevalência da DBP. A implementação de potenciais boas práticas na DBP tem sido adoptada por muitos serviços nas últimas décadas. Objectivo: Comparar cinco unidades portuguesas de cuidados intensivos neonatais no que se refere as práticas clínicas no tratamento dos recém-nascidos de mui-Abstract With the advent of surfactant, prenatal corticosteroids (PNC) and advances in technology, the survival rate of extremely low birth weight (ELBW) infants has improved dramatically. Rates of bronchopulmonary dysplasia (BPD) vary widely among neonatal intensive care units (NICUs) and many studies using multiple interventions have shown some improvement in BPD rates. Implementing potentially better practices to reduce BPD has been an effort made over the last few decades. Aim: To compare five Portuguese NICUs in terms of clinical practices in very low birth weight (VLBW) infants, in order to develop Displasia broncopulmonar: Práticas clínicas em cinco unidades de cuidados intensivos neonatais Bronchopulmonary dysplasia: Clinical practices in five Portuguese neonatal intensive care units Recebido para publicação/received for publication: 09.06.29 Aceite para publicação/accepted for publication: 09.09.08

The most relevant risk factors were low birth weight, severe hyaline membrane disease, duration of respiratory support and oxygen therapy, and nosocomial sepsis. The implementation of potentially better practices to reduce lung injury in neonates must be addressed to improve practices to decrease these risk factors.

The implementation of potentially better practices to reduce lung injury in neonates in Portuguese NICUs, according to each NICU, must be addressed to increase the prescription of PNC, to use a lower FiO2, to be careful with fluid administration in the first weeks of life and to prevent PDA and sepsis. It is necessary to follow guidelines, recommendations or protocols to improve quality in the prevention of BPD.