J Clin Gynecol Obstet

Journal of Clinical Gynecology and Obstetrics, ISSN 1927-1271 print, 1927-128X online, Open Access

Article copyright, the authors; Journal compilation copyright, J Clin Gynecol Obstet and Elmer Press Inc

Journal website http://www.jcgo.org

Original Article

Volume 4, Number 2, June 2015, pages 212-216

A Study of Various Factors Influencing Fetal Scalp Lactate and Their Correlation With Composite Fetal and Neonatal Outcomes

Figure 1. Relationship between fetal scalp lactate and gestational age at birth with linear regression line added.

**Table 1.** Demographic Characteristics for Study Population
Characteristics	FSL < 4.8 mmol/L (n = 230)	FSL ≥ 4.8 mmol/L (n = 96)	Significance (P value)
FSL: fetal scalp lactate; IQR: interquartile range.
Median maternal age (IQR), years	26 (23 - 31)	28 (24 - 32)	0.049
Nulliparous, no. (%)	177 (77%)	71 (74%)	0.56
Median gestational age (IQR), completed weeks	40 (39 - 31)	40 (39 - 41)	0.79
Median time in labor (IQR), h	8.6 (5.3 - 11.6)	6.2 (4.0 - 9.9)	0.001
Median birth weight (IQR), g	3,435 (3,120 - 3,770)	3,345 (3,030 - 3,770)	0.32

Table 1. Demographic Characteristics for Study Population

Characteristics

FSL < 4.8 mmol/L (n = 230)

FSL ≥ 4.8 mmol/L (n = 96)

Significance (P value)

FSL: fetal scalp lactate; IQR: interquartile range.

Median maternal age (IQR), years

26 (23 - 31)

28 (24 - 32)

0.049

Nulliparous, no. (%)

177 (77%)

71 (74%)

0.56

Median gestational age (IQR), completed weeks

40 (39 - 31)

40 (39 - 41)

0.79

Median time in labor (IQR), h

8.6 (5.3 - 11.6)

6.2 (4.0 - 9.9)

0.001

Median birth weight (IQR), g

3,435 (3,120 - 3,770)

3,345 (3,030 - 3,770)

0.32

**Table 2.** Association of Fetal Scalp Lactate With Fetal and Neonatal Outcomes
Outcomes	FSL < 4.8 mmol/L (n = 230)	FSL ≥ 4.8 mmol/L (n = 96)	Odds ratio (95% CI)	Significance (P value)
The combined outcome included the presence of one or more of the following: umbilical artery pH ≤ 7.20, base excess of ≤ -12, Apgar score ≤ 7 at 1 or 5 min, presence of meconium (± operative delivery for fetal distress). FSL: fetal scalp lactate; CI: confidence interval; ODFD: operative delivery for fetal distress.
Operative delivery for fetal distress	84 (36.5%)	86 (89.6%)	14.9 (7.37 - 30.3)	< 0.001
Cord pH < 7.2	52 (22.6%)	31 (32.3%)	1.63 (0.96 - 2.77)	0.067
Cord base excess ≤ -12	6 (2.6%)	5 (5.2%)	2.05 (0.61 - 6.89)	0.311
1 min Apgar ≤ 7	69 (30%)	47 (49%)	2.23 (1.37 - 3.65)	0.001
5 min Apgar ≤ 7	10 (4.3%)	16 (16.7%)	4.40 (1.92 - 10.10)	< 0.001
Special care nursery admission	62 (27.0%)	33 (34.4%)	1.42 (0.85 - 2.37)	0.179
Meconium liquor	97 (42.2%)	35 (36.5%)	0.79 (0.48 - 1.29)	0.338
Combined outcome (including ODFD)	184 (80.0%)	95 (99.0%)	23.8 (3.23 - 175)	< 0.001
Combined outcome (excluding ODFD)	163 (70.9%)	75 (78.1%)	1.47 (0.84 - 2.57)	0.18

Table 2. Association of Fetal Scalp Lactate With Fetal and Neonatal Outcomes

Outcomes

FSL < 4.8 mmol/L (n = 230)

FSL ≥ 4.8 mmol/L (n = 96)

Odds ratio (95% CI)

Significance (P value)

The combined outcome included the presence of one or more of the following: umbilical artery pH ≤ 7.20, base excess of ≤ -12, Apgar score ≤ 7 at 1 or 5 min, presence of meconium (± operative delivery for fetal distress). FSL: fetal scalp lactate; CI: confidence interval; ODFD: operative delivery for fetal distress.

Operative delivery for fetal distress

84 (36.5%)

86 (89.6%)

14.9 (7.37 - 30.3)

< 0.001

Cord pH < 7.2

52 (22.6%)

31 (32.3%)

1.63 (0.96 - 2.77)

0.067

Cord base excess ≤ -12

6 (2.6%)

5 (5.2%)

2.05 (0.61 - 6.89)

0.311

1 min Apgar ≤ 7

69 (30%)

47 (49%)

2.23 (1.37 - 3.65)

0.001

5 min Apgar ≤ 7

10 (4.3%)

16 (16.7%)

4.40 (1.92 - 10.10)

< 0.001

Special care nursery admission

62 (27.0%)

33 (34.4%)

1.42 (0.85 - 2.37)

0.179

Meconium liquor

97 (42.2%)

35 (36.5%)

0.79 (0.48 - 1.29)

0.338

Combined outcome (including ODFD)

184 (80.0%)

95 (99.0%)

23.8 (3.23 - 175)

< 0.001

Combined outcome (excluding ODFD)

163 (70.9%)

75 (78.1%)

1.47 (0.84 - 2.57)

0.18

**Table 3.** Logistic Regression Analysis With Combined Fetal and Neonatal Outcome as Dependent Variable
Independent variable	All factors	Simplified model
CI: confidence interval.
Fetal scalp lactate	1.91 (1.42 - 2.55)	< 0.001	1.90 (1.44-2.51)	< 0.001
Maternal age (years)	1.00 (0.95 - 1.06)	0.98	-	-
Nulliparous	1.36 (0.59 - 3.11)	0.47	-	-
Gestational age	1.18 (0.92 - 1.52)	0.20	-	-
Time in labor (h)	0.95 (0.89 - 1.02)	0.14	-	-
Birth weight	1.00 (0.99 - 1.00)	0.33	-	-
Goodness of fit
Nagelkerke R²	0.20	-	0.17	-
Hosmer and Lemeshow	χ² = 5.68, df = 8	0.68	χ² = 5.61, df = 8	0.69

Table 3. Logistic Regression Analysis With Combined Fetal and Neonatal Outcome as Dependent Variable

Independent variable

All factors

Simplified model

Odds ratio (95% CI)

Significance (P-value)

Odds ratio (95% CI)

Significance (P-value)

CI: confidence interval.

Fetal scalp lactate

1.91 (1.42 - 2.55)

< 0.001

1.90 (1.44-2.51)

< 0.001

Maternal age (years)

1.00 (0.95 - 1.06)

0.98

Nulliparous

1.36 (0.59 - 3.11)

0.47

Gestational age

1.18 (0.92 - 1.52)

0.20

Time in labor (h)

0.95 (0.89 - 1.02)

0.14

Birth weight

1.00 (0.99 - 1.00)

0.33

Goodness of fit

Nagelkerke R²

0.20

0.17

Hosmer and Lemeshow

χ² = 5.68, df = 8

0.68

χ² = 5.61, df = 8

0.69

**Table 4.** Logistic Regression Analysis With Combined Fetal and Neonatal Outcome (Excluding Operative Delivery for Fetal Distress) as Dependent Variable
Independent variable	All factors^†
^†There were no significant predictors after backward stepwise regression.
Fetal scalp lactate	1.10 (0.98 - 1.25)	0.12
Maternal age (years)	0.98 (0.94 - 1.03)	0.95
Nulliparous	1.52 (0.81 - 2.88)	0.2
Gestational age	1.12 (0.92 - 1.36)	0.28
Time in labor (h)	0.96 (0.91 - 1.02)	0.17
Birth weight	1.00 (0.99 - 1.00)	0.31
Goodness of fit
Nagelkerke R²	0.039	-
Hosmer and Lemeshow	χ² = 9.05, df = 8	0.34

Table 4. Logistic Regression Analysis With Combined Fetal and Neonatal Outcome (Excluding Operative Delivery for Fetal Distress) as Dependent Variable

Independent variable

All factors^†

Odds ratio (95% CI)

Significance (P value)

^†There were no significant predictors after backward stepwise regression.

Fetal scalp lactate

1.10 (0.98 - 1.25)

0.12

Maternal age (years)

0.98 (0.94 - 1.03)

0.95

Nulliparous

1.52 (0.81 - 2.88)

0.2

Gestational age

1.12 (0.92 - 1.36)

0.28

Time in labor (h)

0.96 (0.91 - 1.02)

0.17

Birth weight

1.00 (0.99 - 1.00)

0.31

Goodness of fit

Nagelkerke R²

0.039

Hosmer and Lemeshow

χ² = 9.05, df = 8

0.34