J Clin Med Res

Journal of Clinical Medicine Research, ISSN 1918-3003 print, 1918-3011 online, Open Access

Article copyright, the authors; Journal compilation copyright, J Clin Med Res and Elmer Press Inc

Journal website http://www.jocmr.org

Original Article

Volume 7, Number 7, July 2015, pages 511-516

Birth Weight Independently Affects Morbidity and Mortality of Extremely Preterm Neonates

**Table 1.** Demographics and Pregnancy-Related Characteristics in Extremely Preterm Neonates
Epidemiologic characteristics	Neonates (N = 57)
Maternal age (mean ± SD)	31.1 ± 5.8
Gestational week at delivery (mean ± SD)	25.8 ± 1.0
Parity (mean ± SD)	1.6 ± 0.8
Birth weight (mean ± SD)	780.4 ± 176.6
Conception
Natural, n (%)	44 (77.2)
IVF, n (%)	13 (22.8)
Kind of pregnancy
Singleton, n (%)	35 (61.4)
Twin, n (%)	16 (28.1)
Triplets, n (%)	6 (10.5)
Obstetrical complications
IUGR, n (%)	6 (10.5)
PPROM, n (%)	19 (34.5)
Antenatal corticosteroids, n (%)	33 (57.9)
Mode of delivery
Caesarean section, n (%)	39 (68.4)
Neonatal sex
Male, n (%)	33 (57.9)
Female, n (%)	24 (42.1)

Table 1. Demographics and Pregnancy-Related Characteristics in Extremely Preterm Neonates

Epidemiologic characteristics

Neonates (N = 57)

Maternal age (mean ± SD)

31.1 ± 5.8

Gestational week at delivery (mean ± SD)

25.8 ± 1.0

Parity (mean ± SD)

1.6 ± 0.8

Birth weight (mean ± SD)

780.4 ± 176.6

Conception

Natural, n (%)

44 (77.2)

IVF, n (%)

13 (22.8)

Kind of pregnancy

Singleton, n (%)

35 (61.4)

Twin, n (%)

16 (28.1)

Triplets, n (%)

6 (10.5)

Obstetrical complications

IUGR, n (%)

6 (10.5)

PPROM, n (%)

19 (34.5)

Antenatal corticosteroids, n (%)

33 (57.9)

Mode of delivery

Caesarean section, n (%)

39 (68.4)

Neonatal sex

Male, n (%)

33 (57.9)

Female, n (%)

24 (42.1)

**Table 2.** Neonatal Mortality and Morbidity Outcomes of Neonates
Outcomes	Neonates (N = 57)
Apgar score in the first minute (mean ± SD)	4.1 ± 2.6
Apgar score in the fifth minute (mean ± SD)	6.6 ± 2.2
Apgar score ≤ 4 in the first minute, n (%)	27 (47.4)
Apgar score ≤ 7 in the fifth minute, n (%)	28 (49.1)
Respiratory distress syndrome, n (%)	53 (93.0)
Need for resuscitation, n (%)	31 (54.4)
Neonatal asphyxia, n (%)	8 (14.0)
Neonatal sepsis, n (%)	14 (24.6)
Necrotic enterocolitis, n (%)	3 (5.3)
Intraventricular hemorrhage, n (%)	12 (21.1)
Neonatal death, n (%)	30 (52.6)

Table 2. Neonatal Mortality and Morbidity Outcomes of Neonates

Outcomes

Neonates (N = 57)

Apgar score in the first minute (mean ± SD)

4.1 ± 2.6

Apgar score in the fifth minute (mean ± SD)

6.6 ± 2.2

Apgar score ≤ 4 in the first minute, n (%)

27 (47.4)

Apgar score ≤ 7 in the fifth minute, n (%)

28 (49.1)

Respiratory distress syndrome, n (%)

53 (93.0)

Need for resuscitation, n (%)

31 (54.4)

Neonatal asphyxia, n (%)

8 (14.0)

Neonatal sepsis, n (%)

14 (24.6)

Necrotic enterocolitis, n (%)

3 (5.3)

Intraventricular hemorrhage, n (%)

12 (21.1)

Neonatal death, n (%)

30 (52.6)

**Table 3.** Univariate Regression Model Between Pregnancy-Related Parameters and Neonatal Morbidity Outcomes
	Low Apgar in first	Low Apgar in fifth	RDS	IVH	Resuscitation	Asphyxia	NEK	Sepsis
Values are expressed in odds ratio with 95% confidence intervals. *Parameters indicate statistical significance. IUGR: intrauterine growth restriction; PPROM: preterm premature rupture of membranes; RDS: respiratory distress syndrome; IVH: intraventricular hemorrhage; NEK: necrotic enterocolitis.
Gestational age	0.6 (0.3 - 0.99)*	0.6 (0.3 - 0.9)*	1.1 (0.4 - 2.8)	1.4 (0.7 - 2.7)	0.6 (0.3 - 0.99)*	0.7 (0.4 - 1.5)	1.8 (0.5 - 7.3)	1.3 (0.7 - 2.4)
Maternal age	1.0 (0.9 - 1.1)	1.0 (0.9 - 1.1)	1.0 (0.8 - 1.2)	1.0 (0.9 - 1.1)	1.0 (0.9 - 1.1)	1.0 (0.9 - 1.1)	1.2 (0.9 - 1.4)	1.0 (0.9 - 1.2)
Parity	0.8 (0.4 - 1.6)	0.9 (0.5 - 1.9)	0.8 (0.3 - 2.4)	0.4 (0.1 - 1.3)	1.1 (0.6 - 2.2)	1.6 (0.7 - 3.6)	0.6 (0.1 - 4.3)	1.1 (0.5 - 2.4)
IUGR	2.1 (0.4 - 12.3)	1.0 (0.2 - 6.8)	0.3 (0.03 - 3.6)	2.3 (0.9 - 2.8)	0.8 (0.2 - 4.5)	2.5 (0.8 - 3.0)	1.8 (0.7 - 2.2)	0.9 (0.8 - 1.1)
Multiple gestation	0.4 (0.1 - 1.1)	0.4 (0.1 - 1.1)	0.9 (0.6 - 1.4)	1.2 (0.3 - 4.3)	0.3 (0.09 - 0.90)*	0.9 (0.2 - 4.4)	3.4 (0.3 - 39.9)	0.9 (0.4 - 2.4)
PPROM	0.4 (0.1 - 1.1)	0.7 (0.2 - 2.3)	0.5 (0.07 - 3.9)	1.5 (0.4 - 5.5)	0.3 (0.10 - 1.1)	0.6 (0.1 - 3.2)	1.5 (0.1 - 17.4)	1.6 (0.5 - 5.6)
Corticosteroids	2.0 (0.7 - 6.1)	1.7 (0.5 - 5.6)	0.4 (0.04 - 4.5)	1.6 (0.4 - 6.1)	0.8 (0.3 - 2.2)	0.7 (0.2 - 3.1)	0.9 (0.1 - 10.8)	1.0 (0.3 - 3.3)
Mode of delivery	0.9 (0.3 - 2.8)	0.8 (0.2 - 2.9)	0.7 (0.07 - 7.3)	1.5 (0.4 - 6.4)	0.2 (0.1 - 0.8)*	0.2 (0.1 - 0.9)*	1.5 (0.4 - 6.4)	1.2 (0.3 - 4.5)
Birth weight	0.9 (0.9 - 0.98)*	0.9 (0.9 - 0.97)*	0.99 (0.98 - 1.01)	1.0 (0.997 - 1.004)	0.9 (0.9 - 1.01)	0.999 (0.995 - 1.003)	1.007 (0.999 - 1.014)	1.01 (1.01 - 1.04)*
Neonatal sex	0.80 (0.3 - 2.4)	1.7 (0.5 - 5.6)	2.7 (1.9 - 3.8)*	2.3 (0.6 - 8.4)	1.3 (0.5 - 3.8)	2.6 (0.6 - 12.3)	0.7 (0.1 - 7.9)	0. 5(0.1 - 1.7)

Table 3. Univariate Regression Model Between Pregnancy-Related Parameters and Neonatal Morbidity Outcomes

Low Apgar in first

Low Apgar in fifth

RDS

IVH

Resuscitation

Asphyxia

NEK

Sepsis

Values are expressed in odds ratio with 95% confidence intervals. *Parameters indicate statistical significance. IUGR: intrauterine growth restriction; PPROM: preterm premature rupture of membranes; RDS: respiratory distress syndrome; IVH: intraventricular hemorrhage; NEK: necrotic enterocolitis.

Gestational age

0.6 (0.3 - 0.99)*

0.6 (0.3 - 0.9)*

1.1 (0.4 - 2.8)

1.4 (0.7 - 2.7)

0.6 (0.3 - 0.99)*

0.7 (0.4 - 1.5)

1.8 (0.5 - 7.3)

1.3 (0.7 - 2.4)

Maternal age

1.0 (0.9 - 1.1)

1.0 (0.8 - 1.2)

1.0 (0.9 - 1.1)

1.2 (0.9 - 1.4)

1.0 (0.9 - 1.2)

Parity

0.8 (0.4 - 1.6)

0.9 (0.5 - 1.9)

0.8 (0.3 - 2.4)

0.4 (0.1 - 1.3)

1.1 (0.6 - 2.2)

1.6 (0.7 - 3.6)

0.6 (0.1 - 4.3)

1.1 (0.5 - 2.4)

IUGR

2.1 (0.4 - 12.3)

1.0 (0.2 - 6.8)

0.3 (0.03 - 3.6)

2.3 (0.9 - 2.8)

0.8 (0.2 - 4.5)

2.5 (0.8 - 3.0)

1.8 (0.7 - 2.2)

0.9 (0.8 - 1.1)

Multiple gestation

0.4 (0.1 - 1.1)

0.9 (0.6 - 1.4)

1.2 (0.3 - 4.3)

0.3 (0.09 - 0.90)*

0.9 (0.2 - 4.4)

3.4 (0.3 - 39.9)

0.9 (0.4 - 2.4)

PPROM

0.4 (0.1 - 1.1)

0.7 (0.2 - 2.3)

0.5 (0.07 - 3.9)

1.5 (0.4 - 5.5)

0.3 (0.10 - 1.1)

0.6 (0.1 - 3.2)

1.5 (0.1 - 17.4)

1.6 (0.5 - 5.6)

Corticosteroids

2.0 (0.7 - 6.1)

1.7 (0.5 - 5.6)

0.4 (0.04 - 4.5)

1.6 (0.4 - 6.1)

0.8 (0.3 - 2.2)

0.7 (0.2 - 3.1)

0.9 (0.1 - 10.8)

1.0 (0.3 - 3.3)

Mode of delivery

0.9 (0.3 - 2.8)

0.8 (0.2 - 2.9)

0.7 (0.07 - 7.3)

1.5 (0.4 - 6.4)

0.2 (0.1 - 0.8)*

0.2 (0.1 - 0.9)*

1.5 (0.4 - 6.4)

1.2 (0.3 - 4.5)

Birth weight

0.9 (0.9 - 0.98)*

0.9 (0.9 - 0.97)*

0.99 (0.98 - 1.01)

1.0 (0.997 - 1.004)

0.9 (0.9 - 1.01)

0.999 (0.995 - 1.003)

1.007 (0.999 - 1.014)

1.01 (1.01 - 1.04)*

Neonatal sex

0.80 (0.3 - 2.4)

1.7 (0.5 - 5.6)

2.7 (1.9 - 3.8)*

2.3 (0.6 - 8.4)

1.3 (0.5 - 3.8)

2.6 (0.6 - 12.3)

0.7 (0.1 - 7.9)

0. 5(0.1 - 1.7)

**Table 4.** Multivariate Regression Model Between Pregnancy-Related Parameters and Neonatal Morbidity Outcomes
	Low Apgar in first	Low Apgar in fifth	RDS	IVH	Resuscitation	Asphyxia	NEK	Sepsis
Values are expressed in odds ratio with 95% confidence intervals. *Parameters indicate statistical significance. IUGR: intrauterine growth restriction; PPROM: preterm premature rupture of membranes; RDS: respiratory distress syndrome; IVH: intraventricular hemorrhage; NEK: necrotic enterocolitis.
Gestational age	0.7 (0.4 - 1.3)	0.6 (0.3 - 1.3)	-	-	0.8 (0.4 - 1.5)	-	-	-
Maternal age	-	-	-	-	-	-	-	-
Parity	-	-	-	-	-	-	-	-
IUGR	-	-	-	-		-	-	-
Multiple gestation	-	-	-	-	0.4 (0.1 - 1.3)	-	-	-
PPROM	-	-	-	-	-	-	-	-
Corticosteroids	-	-	-	-	-	-	-	-
Mode of delivery	-	-	-	-	0.2 (0.05 - 0.9)*	0.2 (0.1 - 0.9)*	-	-
Birth weight	0.9 (0.9 - 0.98)*	0.9 (0.9 - 0.97)*	-	-	-	-	-	1.01 (1.01 - 1.04)*
Neonatal sex	-	-	2.7 (1.9 - 3.8)*	-	-	-	-	-

Table 4. Multivariate Regression Model Between Pregnancy-Related Parameters and Neonatal Morbidity Outcomes

Low Apgar in first

Low Apgar in fifth

RDS

IVH

Resuscitation

Asphyxia

NEK

Sepsis

Gestational age

0.7 (0.4 - 1.3)

0.6 (0.3 - 1.3)

0.8 (0.4 - 1.5)

Maternal age

Parity

IUGR

Multiple gestation

0.4 (0.1 - 1.3)

PPROM

Corticosteroids

Mode of delivery

0.2 (0.05 - 0.9)*

0.2 (0.1 - 0.9)*

Birth weight

0.9 (0.9 - 0.98)*

0.9 (0.9 - 0.97)*

1.01 (1.01 - 1.04)*

Neonatal sex

2.7 (1.9 - 3.8)*

**Table 5.** Univariate and Multivariate Regression Models Between Pregnancy-Related Parameters and Neonatal Mortality
	Univariate model mortality	Multivariate model mortality
Values are expressed in odds ratio with 95% confidence intervals. *Parameters indicate statistical significance. IUGR: intrauterine growth restriction; PPROM: preterm premature rupture of membranes; RDS: respiratory distress syndrome; IVH: intraventricular hemorrhage; NEK: necrotic enterocolitis.
Gestational age	0.02*	0.5 (0.3 - 0.9)*	0.70	0.6 (0.4 - 1.2)
Maternal age	0.47	1.0 (0.9 - 1.1)	-	-
Parity	0.16	0.6 (0.3 - 1.2)	-	-
IUGR	0.47	1.9 (0.3 - 11.4)	-	-
Multiple gestation	0.39	0.6 (0.2 - 1.8)	-	-
PPROM	0.44	0.6 (0.2 - 2.0)	-	-
Corticosteroids	0.73	1.2 (0.4 - 3.4)	-	-
Mode of delivery	0.78	1.2 (0.4 - 3.6)	-	-
Birth weight	0.007*	0.995 (0.991 - 0.999)*	0.007*	0.97 (0.90 - 0.99)*
Neonatal sex	0.73	0.8 (0.3 - 2.4)	-	-
RDS	0.91	1.1 (0.2 - 8.6)	-	-
IVH	0.03*	6.3 (1.2 - 31.8)*	0.02*	7.9 (1.4 - 45.1)*

Table 5. Univariate and Multivariate Regression Models Between Pregnancy-Related Parameters and Neonatal Mortality

Univariate model mortality

Multivariate model mortality

P value

OR (95% CI)

P value

OR (95% CI)

Gestational age

0.02*

0.5 (0.3 - 0.9)*

0.70

0.6 (0.4 - 1.2)

Maternal age

0.47

1.0 (0.9 - 1.1)

Parity

0.16

0.6 (0.3 - 1.2)

IUGR

0.47

1.9 (0.3 - 11.4)

Multiple gestation

0.39

0.6 (0.2 - 1.8)

PPROM

0.44

0.6 (0.2 - 2.0)

Corticosteroids

0.73

1.2 (0.4 - 3.4)

Mode of delivery

0.78

1.2 (0.4 - 3.6)

Birth weight

0.007*

0.995 (0.991 - 0.999)*

0.007*

0.97 (0.90 - 0.99)*

Neonatal sex

0.73

0.8 (0.3 - 2.4)

RDS

0.91

1.1 (0.2 - 8.6)

IVH

0.03*

6.3 (1.2 - 31.8)*

0.02*

7.9 (1.4 - 45.1)*