Utilization of health-care resources of preterm infants during their first 2 years of life after discharge from neonatal intensive care unit



   Table of Contents   ORIGINAL ARTICLE Year : 2021  |  Volume : 10  |  Issue : 1  |  Page : 37-44

Utilization of health-care resources of preterm infants during their first 2 years of life after discharge from neonatal intensive care unit

Mohammed Yasir Al-Hindi1, Zeyad Mohammed Alshamrani2, Waiel Ahmed Alkhotani2, Abdulrahman Bassam Albassam3, Abdullah Mohammed Amin Tashkandi3, Mansour Abdullah AlQurashi1
1 Department of Pediatrics, Neonatology Division, Ministry of National Guard Health Affairs, King Abdulaziz Medical City; Department of Pediatrics, College of Medicine, King Saud Bin Abdulaziz University for Health Sciences; King Abdullah International Medical Research Center, Ministry of National Guard Health Affairs, Jeddah, Saudi Arabia
2 Department of Pediatrics, College of Medicine, King Saud Bin Abdulaziz University for Health Sciences; King Abdullah International Medical Research Center, Ministry of National Guard Health Affairs, Jeddah, Saudi Arabia
3 Department of Medicine, College of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia

Date of Submission14-Dec-2020Date of Decision24-Dec-2020Date of Acceptance30-Dec-2020Date of Web Publication08-Feb-2021

Correspondence Address:
Dr. Mohammed Yasir Al-Hindi
Department of Pediatrics, Neonatology Division, Ministry of National Guard Health Affairs, King Abdulaziz Medical City, Western Region, Jeddah 21482
Saudi Arabia
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Source of Support: None, Conflict of Interest: None

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DOI: 10.4103/jcn.jcn_204_20

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Background: Preterm birth is the most significant factor for infant morbidity and mortality. Preterm infants are highly vulnerable to substantial comorbidities and need to be admitted to the neonatal intensive care unit (NICU). Prematurity and low birth weight (LBW) of infants, in particular, have been found to have a higher substantial burden on family resources and health-care resources after discharge from the hospital. Objective: To obtain data as a basis for strategic planning and efficient delivery of health-care resources, this study aims to determine the extent of health-care facility utilization among preterm infants during their first 2 years of life after discharge from the NICU. Materials and Methods: This was a retrospective cohort study design by reviewing the electronic medical records of preterm infants (i.e., <37 weeks' gestation) who were discharged from the NICU. Their outcomes were compared to healthy term infants. All examined infants were delivered at King Abdulaziz Medical City, Jeddah, Saudi Arabia, from June 1, 2016, to April 30, 2018. Results: In this single-center study, the NICU admission rate was 8.6%, and 4.18% of those were premature. In terms of facility utilization, preterm infants had a significantly higher frequency of outpatient visits, laboratory, and radiology performed as compared to healthy term infants. Preterm infants were also significantly and more likely to be admitted to the inpatient department. In subgroup analysis, very preterm, extremely preterm, low birth weight (LBW), very LBW (VLBW), and extremely LBW (ELBW) infants had higher outpatient visits and higher laboratory and radiology performed. Conclusions: Preterm infants utilized more health-care resources than healthy term infants. Very preterm, extremely preterm, VLBW, and ELBW infants had more outpatient visits and utilized the laboratory and radiology services more often than other subgroups. This study suggests developing an innovative strategic plan to effectively meet preterm infants' health-care needs, particularly by improving services in mostly utilized hospital resources.

Keywords: Discharge, health-care utilization, low birth weight, neonatal intensive care unit, preterm infants


How to cite this article:
Al-Hindi MY, Alshamrani ZM, Alkhotani WA, Albassam AB, Amin Tashkandi AM, AlQurashi MA. Utilization of health-care resources of preterm infants during their first 2 years of life after discharge from neonatal intensive care unit. J Clin Neonatol 2021;10:37-44
How to cite this URL:
Al-Hindi MY, Alshamrani ZM, Alkhotani WA, Albassam AB, Amin Tashkandi AM, AlQurashi MA. Utilization of health-care resources of preterm infants during their first 2 years of life after discharge from neonatal intensive care unit. J Clin Neonatol [serial online] 2021 [cited 2021 Dec 5];10:37-44. Available from: https://www.jcnonweb.com/text.asp?2021/10/1/37/308844   Introduction Top

Preterm birth is a serious global health problem and the most significant factor for maternal and infant morbidity and mortality. In 2016, the World Health Organization estimated that 15 million babies were born prematurely (before the 37th week of gestation), and approximately 1 million die each year.[1] In Saudi Arabia, particularly, the Ministry of Health reported that 9000–12,000 babies were born prematurely every year (i.e., from the year 2009 to 2013).[2],[3]

A preterm infant has a biological system that is not fully developed, making them vulnerable to significant comorbidities and need to be admitted to neonatal intensive care unit (NICU). These comorbidities include but are not limited to respiratory distress syndrome, chronic lung disease, patent ductus arteriosus, necrotizing enterocolitis, intraventricular hemorrhage, and sepsis, which will increase the utilization of medical resources.[4] Apart from the comorbidities of preterm infants, those who discharge from NICU that were born very early and with low birth weight (LBW) were found to have a higher substantial burden on family resources and health-care resources such as in outpatient settings and in terms of readmissions.[5],[6],[7] These infants are estimated to account for 33%–55% of readmission.[6] Data on comparison to term infants are scarce; moreover, regional and national data are deficient.

Therefore, to obtain data as a basis for strategic planning and efficient delivery of health-care resources, this study aims to determine the extent of health-care facility utilization among preterm infants during their first 2 years of life after discharge from the NICU.

  Materials and Methods Top

This was a retrospective cohort study design by reviewing the electronic medical records of preterm infants (i.e., <37 weeks' gestation) who were discharged from the NICU. Their outcomes were compared to healthy term infants (born between 37 and 41 + 6 weeks' gestation). All examined infants were delivered at King Abdulaziz Medical City (KAMC), Jeddah, Saudi Arabia from June 1, 2016, to April 30, 2018.

Preterm infants comprised the study group, while healthy term infants represent the study control group. Preterm infants (<37 weeks' gestation) who were discharged from NICU were included in the study except for those who were diagnosed with hypoxic-ischemic encephalopathy and major chromosomal or congenital anomalies. All term newborns admitted to NICU were excluded in the study. Healthy term infants were randomly selected utilizing a simple random technique to obtain the 1:1 ratio with preterm infants.

Neonatal characteristics such as gender, age of gestation, and birth weight were obtained. Preterm subcategories were defined as per the WHO into late preterm (32–36 + 6 weeks' gestation), very preterm (28–31 + 6), and extremely preterm (23–27 + 6).[1] Maternal demographic information that includes age, parity, antenatal visit, and the presence of comorbidities was also obtained. All medical records were retrieved using the institution's electronic health record with the approval from the Institutional Review Board of King Abdullah International Medical Research Center, Jeddah, Saudi Arabia.

The case (preterm infants) and control (term infants) groups were compared in terms of frequency of hospital visits (i.e., outpatient visits, emergency [ER] visits, and inpatient readmissions) and facility utilization (i.e., laboratory and radiology) within 24 months after hospital discharge.

All data were entered and analyzed using SPSS version 24.0 for Windows (SPSS, Chicago, IL, USA). Descriptive statistics included means (i.e., for the mother's age) for continuous variables and frequencies and percentages for categorical variables. Independent-samples t-tests, Chi-square tests, and median test were employed to compare frequencies of hospital visits and facility utilization between the groups. Linear regression was used to determine differences and associations between the dependent variables (outpatients' visits, ER visits, inpatient readmissions, radiology, and laboratory utilization) to independent variables (infants and maternal characteristics). Linear regression is also used to predict the frequency of infant's hospital visits and facility utilization up to 24 months of age, considering each covariate (infant and maternal characteristics). Statistical significance for all analyses was set at P < 0.05.

  Results Top

In the institution's electronic health record, we identified 7037 newborns delivered at KAMC, Jeddah, from June 1, 2016, to April 30, 2018. The 6427 (91.33%) were healthy term newborns, while 610 (8.6%) were admitted to NICU. Of the 6429 healthy term newborns, 289 (4.10%) were randomly selected as the study control group, and of the 610 newborns admitted to NICU, 289 (4.10%) of those were preterm infants discharged from NICU and comprised the study case group. These preterm infants comprised 47.3% of total NICU discharge. However, the 315 (4.5%) term infants admitted to NICU and 6 (0.08%) preterm infants with severe congenital and genetic abnormalities were excluded in the study [Figure 1].

In terms of maternal characteristics, mothers of preterm infants were significantly older (30.36 mean age) than mothers of healthy term infants (31.73 mean age) (P < 0.05). Mothers of preterm infants had significantly more comorbidities (111, 38.41%) as compared to mothers of healthy term infants (60, 20.76%) (P < 0.001). In terms of infant characteristics, 191 (66.09%) of preterm infants were born at 32–36 weeks' age of gestation (late preterm), and 156 (53.98%) were categorized in the LBW group (i.e., 1500–2499 g) and 147 (50.87%) were females. Complete maternal and infant characteristics are listed in [Table 1]. As depicted in [Figure 2], respiratory distress (178, 61.59%), LBW (52, 17.99%), and intrauterine growth restriction (26, 8.99%) are the common causes of NICU admissions among preterm infants.

Table 1: Maternal and infant characteristics associated with postnatal outcomes (i.e., preterm and health term)

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Figure 2: Reason for preterm infants' admission to the neonatal intensive care unit. LBW – Low birth weight; IUGR – Intrauterine growth restriction

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In regard to facility utilization, [Table 2] shows that preterm infants had a significantly higher frequency of outpatient visits, laboratory, and radiology utilization (P < 0.05) as compared to healthy term infants. Although preterm infants had a significantly higher frequency in the laboratory performed, they are less likely to have at least one laboratory test as compared to healthy term infants (254, 87.88% vs. 280, 96.88%) (odds ratio [OR]: 23, 95% confidence interval [CI]: 0.110–0.48, P < 0.05). There was no statistically significant difference in the ER visit analysis. In regard to hospital readmission, preterm infants are more likely to be readmitted in inpatient unit (OR: 5.18, 95% CI: 2.70–9.93) [Table 2], particularly caused by respiratory (OR: 6.16, 95% CI: 2.08–18.20) and gastrointestinal diseases (OR: 2.17, 95% CI: 1.97–2.38) [Table 3]. Preterm infants also had higher PICU readmission as compared to healthy term infants 8 (2.77%) versus 2 (0.69%) but statistically not significant (OR: 4.08, 95% CI: 86–19.40, P> 0.05) [Table 2]. In outpatient's visits, preterm infants were more likely to visit the (in rank) specialized neonatal clinic (OR: 2.75, 95% CI: 1.94–3.89, P < 0.05), pediatric clinic (OR: 2.01, 95% CI: 1.39–2.93, P < 0.05), followed by ophthalmology clinics (OR: 11.11, 95% CI: 3.91–31.53, P < 0.05), endocrinology clinics (OR: 11.39, 95% CI: 1.46–88.85, P < 0.05), and neurology clinics (OR: 9.25, 95% CI: 1.16–73.54) [Table 4]. Moreover, preterm infants had higher radiology utilization, particularly in ultrasound (OR: 2.84, 95% CI: 1.69–7.75, P < 0.05) and X-ray (OR: 2.78, 95% CI: 1.86–4.15, P < 0.05) as compared to healthy term infants [Table 5].

Table 2: Hospital visits and hospital facility utilization among term and preterm infants 2 years after discharge from hospital/neonatal intensive care unit

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Table 3: Causes of inpatient readmissions between healthy term infants and preterm infants

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[Table 6] presents linear regression analysis results on hospital utilization of infants during their first 2 years of life after discharge from the hospital considering the maternal and infants' characteristics. Infants of mothers with more than 2 parities had lower utilization of the laboratory services (4.76 laboratory services received) as compared to infants of mothers with 2 or fewer parities (6.97 laboratory services received) (P < 0.05). Maternal characteristics such as age (P > 0.05), antenatal visits (P > 0.05), and comorbidities (P > 0.05) have no significant association with infants' hospital visits and service utilization (P > 0.05). In terms of infants' age of gestation, infants born under the category of very preterm had the highest number of outpatients' visits (9.10 visits) (P < 0.001), followed by extremely preterm (7.90 visits) (P < 0.05) and late preterm (6.16 visits) (P < 0.001), respectively. Very preterm infants also had significantly higher ER visits (1.36 visits) and more likely to be readmitted in the inpatient department (0.38 visits) as compared to late preterm and extremely preterm infants (P < 0.001). In terms of laboratory and radiology service utilization, preterm infants born with lower gestational age had significantly higher laboratory and radiology service utilization. Extremely preterm infants had the highest utilization of laboratory services (15.75 laboratory services received) (P < 0.05), followed by very preterm infants (7.50 laboratory services received) (P < 0.001) and late preterm infants (6.79 laboratory services received) (P < 0.001). Moreover, extremely preterm infants had higher utilization of radiology services (2.75 radiologies performed) (P < 0.001), followed by very preterm infants (2.01 radiologies performed) (P < 0.001) and late preterm (1.07 radiologies performed) (P < 0.05), respectively. In terms of infants' birth weight, infants born under the category of very LBW (VLBW) had significantly higher outpatient visits (10.60 visits) (P < 0.001), followed by extremely LBW (ELBW) (9.22 visits) (P < 0.001). VLBW infants also had significantly higher ER visits (1.67 visits) and more likely to be readmitted to the inpatient department (0.47 readmission) (P < 0.001). In terms of laboratory and radiology service utilization, ELBW had significantly higher utilization of laboratory (11.81 laboratory services received) (P < 0.001) and radiology services (2.943 radiologies performed) (P < 0.001). Nonetheless, infants' gender has no significant association with hospital visits and hospital facility utilization (P > 0.05).

Table 6: Linear regression of infant's hospital visits and hospital facility utilization according to maternal and infant characteristics

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  Discussion Top

The current study showed that the NICU admission rate at our institution was 8.6%, of which 47.3% were preterm newborns who survived to discharge, which represents 4.18% of total live births. These figures were similar to a study done in Northern Military Hospital in Saudi Arabia.[8] This study also showed that preterm infants had higher hospital utilization in outpatient visits, laboratory, radiology, and inpatient readmission compared to healthy term infants.

For mothers of preterm infants, the results were as expected. They were relatively older and had more comorbidities as compared to mothers of healthy term infants. These factors were more likely to contribute to preterm birth, consistent with the large cohort study done in Canada.[9] Comorbidities expose mothers to more psychological and neuroendocrine stress linked to preterm birth.[10],[11] Despite this association to preterm birth (older age and maternal comorbidities), it has no direct association, by linear regression analysis, with increased health-care facility utilization by preterm infants after their discharge from NICU. This finding could explain that increased utilization is due to preterm infants' vulnerable body system biology and their associated comorbidities developed during their NICU stay rather than maternal factors.[4] This finding was similar to a population-based study in Norway in the context of very preterm VLBW infants.[12] Nevertheless, in our study, mothers who had >2 parities had a lower number of hospital utilization, particularly significant to laboratory performed than mothers who had ≤2 parities. A previous study by Klitkou et al.[12] showed mixing effects of maternal parity; however, their analysis was based on parity of 1, our analysis was based on more than two (>2) parities. Such an interesting finding should be explored in further trials.

Specialized neonatal clinics in our institution are considered as specialty clinics under the pediatric department. These clinics serve to term infants (i.e., study controls), discharged from postnatal wards, and those required follow-ups for minor issues such as jaundice, laboratory results, and weight gain. If there is a need for further care, a referral to a pediatric clinic is made. For preterm infants (i.e., study cases), neonatal clinics follow them as per the American Academy of Pediatrics recommendations that include nutrition, growth, and developmental screening.[5] If any abnormality is detected, patients are referred to pediatric specialty clinics with their various subspecialties.

As per the results of this study [Table 4], clearly, preterm infants follow neonatal clinics more than term infants (OR: 2.75, 95% CI: 1.94–3.89). Moreover, linear regression results showed a further increase in predicted utilization with lower gestational age and birth weight categories. This is much needed as preterm infants are more likely to suffer from short-term (e.g., malnutrition and growth failure) and long-term (e.g., neurodevelopmental disabilities) complications.[4] Preterm infants are more likely to be referred to pediatric clinics (OR: 2.01, 95% CI: 1.39–2.93). Furthermore, subspecialty clinics, indicating the need for more complex and multidisciplinary care, are more likely to be visited by preterm infants. As shown in [Table 4], neurology, endocrinology, and ophthalmology were more likely needed by preterm infants. There is a trend toward increased visits to respiratory clinics (β = 0.057); however, the limited availability of this specialty in our center limits the referral. Hence, majority are managed by pediatric clinics. Only a few published data discussed comparing the utilization of various specialties outpatient visits.[8],[13] Others described such visits in preterm infants with comparisons made for gestational age subcategories.[14] Our study adds to such a pressing need.

Almost all term infants will do the laboratory as part of the screening for iron-deficiency anemia program. This reflects why they are more likely to have at least one laboratory. However, the frequency of laboratory utilization was higher in the preterm group. This is confirmed by the linear regression, which predicted lower categories of gestation or birth weights had more laboratories compared to term and NBW infants. Based on our knowledge, this finding is not reported in the literature before. It is expected for a preterm infant to have complex care and the need for nutritional deficiency monitoring and bone health assessment, which is being accomplished by observing the growth and frequent laboratory parameters monitoring.[4]

For radiological procedures, it was noticed that preterm infants utilized significantly more radiological procedures that include X-rays and ultrasound [Table 5]. Moreover, lower subcategories of gestational age and birth weight were significantly predicted to have more radiological procedures. This finding is also not reported in the literature. It is well documented that preterm infants have more morbidities that require more visits to ER and admissions and outpatient visits in corresponding subspecialties. Hence, more and frequent radiological images are often needed.

For ER visits, our study showed that preterm infants tend to require more ER but not statistically significant; however, linear regression showed that very preterm and VLBW infants are predicted to have more frequent ER visits, which is consistent with the literature.[13] ER in our society is still considered as an urgent care clinic, especially beyond working hours, which leads to more frequent visits by healthy infants suffering from minor illnesses. This could dilute the differences in the frequency of visits to the ER between the groups.

Our study showed that preterm infants had significantly 5 times higher odds of at least one inpatient readmission. The most common cause of admission was respiratory illnesses, followed by gastrointestinal illnesses [Table 3], consistent with well-known literature.[4],[13] Furthermore, in the result of linear regression, the lower the gestational age and birth weight, the higher risks for inpatient readmission [Table 6]. These results showed no difference with previous literature that categorized preterm infants according to gestational age groups and birth weight groups for subgroup analysis.[8],[13],[14],[15] Preterm and LBW infants' readmission indicates a compromised immune system and vulnerability to psychosocial stress.[4]

For PICU admission, preterm infants tend to have more admissions, however, not statistically significant. Our study was underpowered to detect a difference; however, we speculate based on the literature that such a significant difference could be achieved with a bigger sample size.[14]

Our study is a retrospective cohort study with healthy term infants as controls. We also excluded from analysis infants with congenital or chromosomal anomalies that are well known to utilize more health-care services due to the complexity of their conditions and the requirement of multidisciplinary team management. Finally, our study is the first in Saudi Arabia, at least, to report the laboratory and radiology utilization.

The limitations of this study include a single center and small sample size. However, our results, for the hospital visits and readmission, do concur with large, population-based, and neonatal networks. The results of increased health-care utilization would be considered sufficient to give the message to corporate health management administration to facilitate and allocate resources for preterm infants within its jurisdiction. We recommend further study in a large multicenter with a more representative sample of a population that includes nonmilitary patients. It will certainly address the problems of our unique health-care system in Saudi Arabia that are composed of multiple sectors such as the Ministry of Health, private, university, and various military hospital systems. Such a study should include a multidomain parental socioeconomic status scale and antenatal risk score to examine these effects and determinants on health-care utilization.[16],[17]

  Conclusions Top

Preterm infants utilized more health-care resources than healthy term infants. Very preterm, extremely preterm, VLBW, and ELBW infants had more outpatient visits and utilized the laboratory and radiology services more often than other subgroups. This study suggests developing an innovative strategic plan to improve the services in mostly utilized hospital resources (i.e., outpatients, laboratory, and radiology) by preterm infants to meet their health-care needs effectively.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 

  References Top
1.WHO, “Preterm Birth,” February 19, 2018. Available from: https://www.who.int/news-room/fact-sheets/detail/preterm-birth. [Last accessed 2020 Nov 15].  Back to cited text no. 1
    2.Ministry of Health, Saudi Arabia, “Health Statistics Annual Book,” 2013. Available from: https://www.moh.gov.sa/en/Ministry/Statistics/book/Documents/Statistics-Book-1434.pdf. [Last accessed 2020 Nov 13].  Back to cited text no. 2
    3.Arab News, “Saudi Arabia Delivers 'Early Warning' on Preterm Births,” November 21, 2019. Available from: https://www.arabnews.com/node/1587341/saudi-arabia. [Last accessed 2020 Nov 10].  Back to cited text no. 3
    4.Behrman RE, Butler AS, editors. “Institute of Medicine (US) Committee on Understanding Premature Birth and Assuring Healthy Outcomes.” In: Preterm Birth: Causes, Consequences, and Prevention. Vol. 772. Washington, DC: National Academies Press; 2007.  Back to cited text no. 4
    5.American Academy of Pediatrics Committee on Fetus and Newborn. Hospital discharge of the high-risk neonate. Pediatrics 2008;122:1119-26.  Back to cited text no. 5
    6.Lee JH, Chang YS; Committee on Data Collection and Statistical Analysis, the Korean Society of Neonatology. Use of medical resources by preterm infants born at less than 33 weeks' gestation following discharge from the neonatal intensive care unit in Korea. J Korean Med Sci 2015;30 Suppl 1:S95-103.  Back to cited text no. 6
    7.Beck S, Wojdyla D, Say L, Betran AP, Merialdi M, Requejo JH, et al. The worldwide incidence of preterm birth: A systematic review of maternal mortality and morbidity. Bull World Health Organ 2010;88:31-8.  Back to cited text no. 7
    8.Al-Qahtani DA, Imtiaz ML, Al-Dusari SN, Mustafa AP, Rafael R. Frequency of visits for health care by low-birth-weight and preterm Saudi infants in the first year of life. East Mediterr Health J 2005;11:732-44.  Back to cited text no. 8
    9.Fuchs F, Monet B, Ducruet T, Chaillet N, Audibert F. Effect of maternal age on the risk of preterm birth: A large cohort study. PLoS One 2018;13:e0191002.  Back to cited text no. 9
    10.Hobel CJ, Dunkel-Schetter C, Roesch SC, Castro LC, Arora CP. Maternal plasma corticotropin-releasing hormone associated with stress at 20 weeks' gestation in pregnancies ending in preterm delivery. Am J Obstet Gynecol 1999;180:S257-63.  Back to cited text no. 10
    11.Rich-Edwards JW, Grizzard TA. Psychosocial stress and neuroendocrine mechanisms in preterm delivery. Am J Obstet Gynecol 2005;192:S30-5.  Back to cited text no. 11
    12.Klitkou ST, Iversen T, Stensvold HJ, Rønnestad A. Use of hospital-based health care services among children aged 1 through 9 years who were born very preterm – A population-based study. BMC Health Serv Res 2017;17:571.  Back to cited text no. 12
    13.McLaurin KK, Wade SW, Kong AM, Diakun D, Olajide IR, Germano J. Characteristics and health care utilization of otherwise healthy commercially and Medicaid-insured preterm and full-term infants in the US. Pediatric Health Med Ther 2019;10:21-31.  Back to cited text no. 13
    14.Ambalavanan N, Carlo WA, McDonald SA, Yao Q, Das A, Higgins RD, et al. Identification of extremely premature infants at high risk of rehospitalization. Pediatrics 2011;128:e1216-25.  Back to cited text no. 14
    15.Doyle LW, Ford G, Davis N. Health and hospitalizations after discharge in extremely low birth weight infants. Semin Neonatol 2003;8:137-45.  Back to cited text no. 15
    16.Al-Hindi MY, Aljuhani H, Alnajjar AR, Alessa S, Alqurashi M, Faden YA. Examining the association between parental socioeconomic status and preterm birth using multidomain social determinants scale in a tertiary care center in Saudi Arabia. Cureus 2020;12:e10506.  Back to cited text no. 16
    17.Al-Hindi MY, Al Sayari TA, Al Solami R, Al Baiti AK, Alnemri JA, Mirza IM, et al. Association of Antenatal Risk Score With Maternal and Neonatal Mortality and Morbidity. Cureus. 2020;12(12):e12230.  Back to cited text no. 17
    
  [Figure 1], [Figure 2]
 
 
  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]
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