Population-based cohort study assessing the strength of the relationship between the APGAR score at 5 minutes after birth and the risk of neonatal and infant mortality. The study collected mortality data from singleton livebirths in Scotland, UK for a period of 18 years. The study only included births in women older than the age of 10 years with a gestational age at delivery between 24 and 44 weeks, all deaths due to isoimmunisation or congenital anomalies were excluded. Statistical analyses included a binomial log-linear modelling and relative risks (RR) for neonatal and infant deaths with different Apgar scores. Apgar scores were divided into low (scores 0-3), intermediate (scores 4-6) and normal (scores 7-10) at 5 minutes after birth. The results were arranged by gestational age at birth. Results showed the strongest association between deaths attributed to anoxia and low Apgar scores for term infants (RR 961.7, 95% CI 681.3–1357.5) and preterm infants (141.7, 90.1–222.8). A low Apgar score (0-3) was associated with early neonatal death (adjusted RR 359.4, 95% CI 277.3-465.9), late neonatal death (adjusted RR 30.5, 95% CI 18.0-51.6), and infant death (adjusted RR 50.2, 95% CI 42.8-59.0). Overall, the results of the study found a strong association between low Apgar scores at 5 minutes and increased risk of neonatal and infant death.

Review article describing the proposal by Virginia Apgar for the new method of evaluation of the newborn infant. The purpose of this paper was to establish a classification system for newborn infants to compare the results of types of maternal pain relief used, results of resuscitation and obstetric practices. Dr. Apgar considered various factors and signs that could correlate with an infant's condition at birth and after several considerations five were selected; heart rate, respiratory efforts, reflex irritability, muscle tone and color. Dr. Apgar's first study of more than 1025 infants born aliveat Columbia Presbyterian Medical Center established that scores of 8 or higher correlated with good condition, whereas scores of 2 or less correlated with poor condition. Scores between 3 and 7 were deemed as fair.  Dr. Apgar found that mature infants at 1 minute after birth receiving 0-2 scores had a neonatal death rate of 14%; those scoring 3-7 had a death rate of 1.1%; and those in the 8-10 score group had a death rate of 0.13%. Dr. Apgar's work and the studies that followed established the score as the standard throughout the world that remains an easy and effective method for assessing the effectiveness of resuscitation and vitality of infants.

Retrospective analysis assessing whether the 5 minute Apgar score is associated with mortality in extremely preterm infants after transfer from the delivery hospital to an all referral nenonatal intensive care unit at an average age of 10 days. The analysis looked at data from 454 infants born between 2004 and 2010 with a gestational age of less than 27 weeks. Demographic data was collected, along with 1 and 5 minute Apgar scores. Data was presented as mean 

± standard deviation, median and interquartile range (IQR) or percentages. Results included a median Apgar score of 3 at 1 minute (IQR 2-6) and 6 at 5 minutes (IQR 4-7). The Apgar score increased from 1 to 5 minutes by 2.0 ± 1.7 (p<0.001), and scores < 5 at 5 minutes was shown to be associated with an increased in mortality (p<0.05), but not morbidities. Findings of the study supported the importance of the Apgar score given at delivery in the extremely preterm infants.

Statement published in the American Academy of Pediatrics highlighting the limitations and utility of the Apgar score. The Apgar score compromises 5 components; color of the infant, heart rate, reflexes, muscle tone and respiration, each of which is assigned a score of 0,1 or 2. The score is calculated 1 or 5 minutes after birth and at 5 minutes intervals thereafter. The Apgar score is useful for relaying information about the infant's overall status and response to resuscitation, however it is not used to determine the need for initial resuscitation, what steps are necessary or when to use them. However, the article highlights that an Apgar score that remains at 0 after 10 minutes of age might be useful in determining whether resuscitation efforts should be continued. Other limitations highlighted in the article include the numerous factors that can influence the Apgar score, such as maternal sedation, congenital malformations, gestational age, trauma, and interobserver variability. Despite its limitations, the use of the Apgar score is still encouraged and recommended.

Cohort study aimed at examining the risk of recurrence of low Apgar scores in a subsequent term singleton pregnancy. Study population included a total of 190,725 women with two subsequent singleton term live births between 1999 and 2007 in the Netherlands. The main objectives analyzed were the prevalence of birth asphyxia and the number of 5 minute Apgar scores below 7. Results showed that the risk for an Apgar score < 7 in the first pregnancy was twice as higher than in the subsequent pregnancies (0.99% versus 0.50%). For infants with asphyxia in the first pregnancy, the risk of recurrence of a low Apgar score was 1.1% (odds ratio 2.1, 95% confidence interval 1.4-3.3). Overall results demonstrate that women with birth asphyxia of the first born have a higher risk of renewed asphyxia at the next birth.

Article describing the history of the Apgar score and assessing its usefulness in the clinical field. The Apgar score is assigned at 1 minute and 5 minutes after birth and it has had a magnificent impact on neonatal resuscitation. Early studies of the Apgar score demonstrated the inverse relation between neonatal mortality and Apgar scores at 1 minute. When the Apgar score was developed, obstetric practices, anaesthesia, resuscitation of newborn infants, and neonatal intensive care differed from current practices. A study looking at births between 1992 and 2010 confirmed the association between low Apgar scores and the risk of neonatal and infant death, thus re-estabishing its role in clinical practice.