Introduction
The neonatal period is the most vulnerable period for a child’s survival. The child’s risk of dying is the highest in the first 28 days of life. One of the leading causes of neonatal death is birth asphyxia. The World Health Organization (WHO) defines birth asphyxia as “the failure to initiate and sustain breathing at birth”.(1) In birth asphyxia, the marked impairment of blood flow or gas exchange to or from the fetus in the period before, during or directly after birth, leads to progressive hypoxemia, hypercapnia, and significant metabolic acidosis. Globally, birth asphyxia is responsible for an estimated 900,000 neonatal deaths each year, and it is the main cause of death in term infants admitted to the neonatal intensive care unit (NICU).(2, 3) Furthermore, birth asphyxia is a major cause of morbidity with both significant short and long-term consequences.(4, 5)
The Apgar score provides a rapid assessment of the infant’s clinical status immediately after birth and of the response to resuscitation if needed.(6, 7) In term infants without severe congenital malformations, a low 5-minute Apgar score has the best predictive value for neonatal mortality and is highly associated with subsequent neurological disability such as cerebral palsy, cognitive impairment, attention deficit/hyperactivity disorder, and epilepsy even in the era of therapeutic hypothermia.(8-12)
Previous studies showed that the risk of a low 5-minute Apgar score <7 among term singletons slightly decreased in the period 1999-2009 in the Netherlands, but significantly increased in the subsequent period (from 9.9/1000 in 2010 to 10.9/1000 in 2014,p< 0.001).(13-15) This latter observation is worrisome. An association with epidural analgesia was suggested, because the study presenting data from 2010-2014 also showed that the strongest risk factor for an Apgar score <7 was the use of epidural analgesia.(14) To the best of our knowledge, there are no studies presenting more recent trends in the Netherlands for a low Apgar score in the Netherlands, including Apgar score <4.
The primary aim of the present study was to investigate recent trends in indicators of birth asphyxia over the last decade (2010-2019) in the Netherlands, with a low 5-minute Apgar score as main outcome measure. The secondary aim was to identify risk factors for a low Apgar score, and to describe trends over time in low Apgar scores in subgroups of infants based on obstetric interventions and level of care.