Mortality in Neonatal Intensive Care Units in Iran: A Systematic Review and Meta-Analysis

Document Type: Review Article


1 Department of Pediatrics, School of Medicine, Ilam University of Medical Sciences, Ilam, Iran

2 Faculty of Medicine, Dezful University of Medical Sciences, Dezful, Iran

3 Faculty of Medicine, Ilam University of Medical Sciences, Ilam, Iran

4 Department of Pediatrics, Behbahan Faculty of Medical Sciences, Behbahan, Iran


Background: Neonatal mortality rate is an important health index. The present study was conducted to determine the mortality rate and its causes in neonatal intensive care units (NICUS) in Iran.
Methods: Online search was done without time limit until June 2018 in several databases, such as PubMed, Web of Science (ISI), Scopus, Magiran, Barakat Knowledge Network System, SID, Iranian National Library, Regional Information Center for Science and Technology (RICST), Google Scholar search engine, and Iranian journals. The articles were qualitatively assessed after evaluating the inclusion and exclusion criteria. The Cochran's Q test and I2 index were used to determine the heterogeneity between studies. Meta-analysis was done based on a random effects model using Comprehensive Meta-Analysis Software (version 2).
Results: Thirty-one eligible studies were analyzed. The mortality rate in 24,995 neonates admitted to NICUs in Iran was estimated to be 11.40% (95% CI: 9.10-14.20). The lowest mortality rate reported as 7.70% (95% CI: 6.01-9.82) was related to the Center of Iran, and the highest mortality rate was reported as 19.26% (95% CI: 15.82-23.24) in the west of Iran. In this regard, the difference was statistically significant (P<0.001). The most common causes of mortality in NICUs in Iran were prematurity (44.14% [95% CI: 31.95-57.08]), respiratory distress syndrome (RDS) (31.93% [95% CI: 22.83-42.66]), congenital malformation (16.09% [95% CI: 12.85-19.95]), septicemia (12.66% [95% CI: 8.87-17.75]), and asphyxia (7.58% [95% CI: 4.63-12.19]).
Conclusion: The most common causes of mortality in Iranian neonates were prematurity, RDS, and congenital anomalies. We also found the mortality rate to be acceptable (11.4%). To reduce the mortality rate, we recommend performing prenatal screening tests and genetic counseling. In addition, maternal care during pregnancy should be improved to reduce premature delivery.


1. Davazdah ES, Abde YZ, Montazeri M, Bashardoust N. Social factors associated with infants’ mortality. J Shahrekord Univ Med Sci. 2001; 3(2):67-72.

2. Yu VY. Global, regional and national perinatal and neonatal mortality. J Perinatal Med. 2003; 31(5):376-9.

3. Stoll B, Kliegman R. Overview of mortality and morbidity. In: Behrman RE, Kliegman RM, Jenson HB, editor. Nelson textbook of pediatrics. Philadelphia: Saunders; 2004.

 4. World Health Organization. Make every mother and child count. Geneva: World Health Organization; 2005.

5. World Health Organization. Neonatal and perinatal mortality: country, regional and global estimates. Geneva: World Health Organization; 2006.

 6. Chow S, Chow R, Popovic M, Lam M, Popovic M, Merrick J, et al. A selected review of the mortality rates of neonatal intensive care units. Front Public Health. 2015; 3:225.

 7. Zupancic JA, Richardson DK. Characterization of the triage process in neonatal intensive care. Pediatrics. 1998; 102(6):1432-6.

8. Kamath BD, Macguire ER, McClure EM, Goldenberg RL, Jobe AH. Neonatal mortality from respiratory distress syndrome: lessons for low-resource countries. Pediatrics. 2011; 127(6):1139-46. 9. Azami M, Jaafari Z, Masoumi M, Shohani M, Badfar G, Mahmudi L, et al. The etiology and prevalence of urinary tract infection and asymptomatic bacteriuria in pregnant women in Iran: a systematic review and Meta-analysis. BMC Urology. 2019; 19(1):43.

10. Azami M, Moslemirad M, YektaKooshali MH, Rahmati S, Soleymani A, Shamloo MBB, et al. Workplace violence against Iranian nurses: a systematic review and meta-analysis. Violence and victims. 2018;33(6):1148-75.

11. Moher D, Liberati A, Tetzlaff J, Altman DG. Preferred reporting items for systematic reviews and meta‚Äźanalyses: the PRISMA Statement. Ann Intern Med. 2009; 151(4):264-9.

12. Wells G. The Newcastle-Ottawa Scale (NOS) for assessing the quality of nonrandomised studies in meta-analysis. Available at: URL: http://www.ohri. ca/programs/clinical_epidemiology.oxford.Htm; 2004.

13. Green S. Cochrane handbook for systematic reviews of interventions version 5.1. 0. London: The Cochrane Collaboration; 2011.

 14. Higgins JP, Thompson SG, Deeks JJ, Altman DG. Measuring inconsistency in meta-analyses. BMJ. 2003; 327(7414):557-60.

 15. Javanmardi Z, Marjan Beigi M, Nouhpisheh E. Investigating about the causes of neonates’ death in the hospitals of Isfahan Province. Sci J Forensic Med. 2010; 4(4):229-33.

 16. Javanmardi Z, Beigi M, Nouhpisheh E, Memarzadeh M, Radan MR. The reported causes for neonatal death in hospitals of Isfahan province in 2005. Iran J Nurs Midwifery Res. 2008; 13(2):87-9.

 17. Zeinalzadeh AH, Khodaei R, Heidarzadeh M, Mirnia K. Causes of neonatal mortality in the neonatal intensive care unit of Taleghani Hospital. Iran J Neonatol. 2017; 8(3):58-61.

18. Jaberi Z, Gholami-Fesharaki M, Rahmati-Najarkolaei F, Saburi A. Mortality rate of one neonatal intensive care unit in Tehran, Iran. J Clin Neonatol. 2013; 2(1):52.

19. Mirzarahimi M, Abedi A, Shahnazi F, Saadati H, Enteshari A. Causes and rate of mortality among the newborns in NICU and newborns unit at Imam Khomeini and Alavi Hospitals in Ardabil from September 2006 to September 2007. J Ardabil Univ Med Sci. 2008; 8(4):424-30.

20. Safari H. Assessing the rate and causes of mortality in neonatal care units in 2006-2008. Tehran: Shahid Beheshti University of Medical Sciences; 2009.

21. Aramesh MR, Malekian A, Dehdashtian M, Shahori A, Monjezi L. Determination of neonatal mortality causes among neonates admitted in NICU at Imam Khomeini Hospital, Ahwaz, 2011-2012. Razi J Med Sci. 2014; 21(120):36-43.

22. ArefNejad M, Jaberi N, Khalilipour E, Isfahani PA. Survey of neonatal mortality in NICU in Amiralmomenin Hospital of Zabol University of Medical Sciences in 2014: a short report. J Rafsanjan Univ Med Sci. 2016; 15(1):91-8.

 23. Ziba M, Movahedian Amir H, Gholam AM. Admission patterns and outcomes in a neonatal unit in Kashan, Iran. Early Hum Dev. 2008; 84:S14.

 24. Fallahi M, Joudaki N. Evaluation of causes of neonatal mortality in Shohadaye Tajrish Hospital, during years 2004-2007. Pajoohandeh J. 2009; 14(1):43-6.

 25. Sareshtedari M, Shahamat H, Sadeghi T. Causes and related factors of neonatal mortality in Qazvin NICU, 2010. Hakim Health Syst Res. 2012; 14(4):227-32.

 26. Bala Ghafari A, Siamian H, Aligolbandi K, Rashida S. Survey of characteristics of neonatal death in neonatal intensive care unit of Boo-Ali Sina educational & therapeutic. J Mazandaran Univ Med Sci. 2010; 19(74):79-83.

27. Hoseini BL, Sadati ZM, Rakhshani MH. Assessment of neonatal mortality in the neonatal intensive care unit in Sabzevar city for the period of 2006-2013. Electron Physician. 2015; 7(7):1494-9.

 28. Mirfazeli A, Sedehi M, Golalipour MJ. Neonatal and prenatal causes of death in Gorgan-North of Iran. Med J Islamic Republic Iran. 2014; 28:43.

 29. Basiri B, Ashari FE, Shokouhi M, Sabzehei MK. Neonatal mortality and its main determinants in premature infants hospitalized in neonatal intensive care unit in Fatemieh Hospital, Hamadan, Iran. J Compr Pediatr. 2015; 6(3):e26965.

 30. Khani S, Mohamadpour RA, Ghaffari Saravi V, Abdollahi F. 200and governmental hospitals in Sari by survival analysis technique during 2005-7. J Mazandaran Univ Med Sci. 2008; 17(62):54-62.

 31. Azami M, Jasemi S, Khalifpur Y, Badfar G. Causes and rate mortality among neonatal intensive care unit in Ahvaz during 2015-2016. Ahvaz: Ahvaz Jundishapur University of Medical Sciences; 2016. 32. Sabzehei MK, Basiri B, Shokouhi M, Eghbalian F, Eslamian MH. Causes and risk factors associated to neonatal mortality in neonatal intensive care unit (NICU) in Besat Hospital Hamadan Iran in 2015 to 2016. Int J Pediatr. 2018; 6(9):8185-94.

33. Babaei H, Dehghan M, Mohammadi Pirkashani L. Study of causes of neonatal mortality and its related factors in the neonatal intensive care unit of Imam Reza Hospital in Kermanshah during (2014-2016). Int J Pediatr. 2018; 6(5):7641-49.

34. Taheri F, Sharifzadeh G, Kaheni S, Saboori G. Epidemiology of neonates hospitalized in NICU of Valieasr Hospital, Birjand, in 2005-2006. Mod Care J. 2007; 4(1):29-34.

35. Eventov-Friedman S, Kanevsky H, Bar-Oz B. Neonatal end-of-life care: a single-center NICU experience in Israel over a decade. Pediatrics. 2013; 131(6):e1889-96.

36. Sankaran K, Chien LY, Walker R, Seshia M, Ohlsson A, Lee S. K, et al. Variations in mortality rates among Canadian neonatal intensive care units. CMAJ. 2002; 166(2):173-8.

 37. Simpson CD, Xiang YY, Hellmann J, Tomlinson C. Trends in cause-specific mortality at a Canadian out born NICU. Pediatrics. 2010; 126(6):e1538-44.

38. Abdel-Latif ME, Nowak G, Bajuk B, Glass K, Harley D. Variation in hospital mortality in an Australian neonatal intensive care unit network. Arch Dis Child Fetal Neonatal Ed. 2018; 103(4):F331-6.

 39. Zardo MS, Procianoy RS. Comparison between different mortality risk scores in a neonatal intensive care unit. Rev Saude Publica. 2003; 37(5):591-6.

40. Seoud I, Rasha M, El-Din RN, Said RN, Hessin HA. Predictors of neonatal mortality in intensive care unit in children’s hospital, Cairo University. Alexandria J Pediatr. 2005; 19(1):93-7.

41. Arafa MA, Alshehri MA. Predictors of neonatal mortality in the intensive care unit in Abha, Saudi Arabia. Saudi Med J. 2003; 24(12):1374-6.

42. Manktelow BN, Seaton SE, Field DJ, Draper ES. Population-based estimates of in-unit survival for very preterm infants. Pediatrics. 2013; 131(2): e425-32.

43. Ekwochi U, Ndu IK, Nwokoye IC, Ezenwosu OU, Amadi OF, Osuorah DIC. Pattern of morbidity and mortality of newborns admitted into the sick and special care baby unit of Enugu state University Teaching Hospital, Enugu state. Niger J Clin Pract. 2014; 17(3):346-51.

44. Costa S, Rodrigues M, Centeno MJ, Martins A, Vilan A, Brandão O, et al. Diagnosis and cause of death in a neonatal intensive care unit – How important is autopsy? J Matern Fetal Neonatal Med. 2011; 24(5):760-3.

45. Parappil H, Rahman S, Salama H, Rifai HA, Parambil NK, Ansari WE. Outcomes of 28+1 to 32+0 weeks gestation babies in the state of Qatar: finding facility-based cost effective options for improving the survival of preterm neonates in low income countries. Int J Environ Res Public Health. 2010; 7(6):2526-42.

46. Pepler PT, Uys DW, Nel DG. Predicting mortality and length-of-stay for neonatal admissions to private hospital neonatal intensive care units: a South African retrospective study. Afr Health Sci. 2012; 12(2):166-73.

 47. Musooko M, Kakaire O, Nakimuli A, Nakubulwa S, Nankunda J, Osinde MO, et al. Incidence and risk factors for early neonatal mortality in ne