Predicting low Apgar scores of infants weighing less than 1000 grams: the effect of corticosteroids

[Perinatal risk factors for the occurrence of singleton apparently stillborn infants]

OBJECTIVES

To identify the perinatal risk factors for the occurrence of singleton apparently stillborn infants.

METHODS

This was a case-control study. A total of 154 singleton neonates with gestational age ≥28 weeks and Apgar score of 0-1 who were subsequently successfully resuscitated in the Obstetrics and Gynecology Hospital of Fudan University from January 2006 to December 2015 were enrolled as the case group (apparently stillborn group). A total of 616 singleton infants born from January 2006 to December 2015 (1-minute Apgar score >1) were randomly selected in a 1:4 ratio as the control group. Univariate analysis and multivariate logistic regression were used to analyze the perinatal risk factors for the occurrence of apparently stillborn infants.

RESULTS

The gestational age and birth weight in the apparently stillborn group were significantly lower than those in the control group (P<0.05). The incidences of fetal hydrops, cord prolapse, grade III meconium-stained amniotic fluid, placental abruption, breech presentation, severe pre-eclampsia, maternal general anesthesia at delivery, abnormal antenatal fetal heart monitoring and decreased fetal movement were significantly higher in the apparently stillborn group than those in the control group (P<0.05). The multivariate logistic analysis showed that the mother had general anesthesia at delivery (OR=34.520), decreased antenatal fetal movement (OR=28.168),placental abruption (OR=15.641), grade III meconium-stained amniotic fluid (OR=6.365), abnormal antenatal fetal heart monitoring (OR=5.739), and breech presentation (OR=2.614) were risk factors for the occurrence of apparently stillborn infants (P<0.05), while higher gestational age was a protective factor (OR=0.686, P<0.05).

CONCLUSIONS

Attention needs to be paid to mothers with abnormal prenatal fetal heart monitoring, decreased fetal movement, preterm labor, placental abruption, breech presentation, grade III meconium-stained amniotic fluid, and general anesthesia. Preparations for resuscitation should be done to rescue apparently stillborn infants.

Preterm Birth: A Prominent Risk Factor for Low Apgar Scores

OBJECTIVE

To determine predictive risk factors for Apgar scores < 7 at 5 minutes at two hospitals providing tertiary care and secondary care, respectively.

METHODS

A retrospective registry cohort study of 21126 births (2006-2010) using data from digital medical records. Risk factors were analyzed by logistic regression analyses.

RESULTS

AS(5 min) < 7 was multivariately associated with the following: preterm birth; gestational week 32 + 0-36 + 6, OR = 3.9 (95% CI 2.9-5.3); week 28 + 0-31 + 6, OR = 8 (5-12); week < 28 + 0, OR = 15 (8-29); postterm birth, OR = 2.0 (1.7-2.3); multiple pregnancy, OR = 3.53 (1.79-6.96); previous cesarean section, OR = 3.67 (2.31-5.81); BMI 25-29, OR = 1.30 (1.09-1.55); BMI ≥ 30  OR = 1.70 (1.20-2.41); nonnormal CTG at admission, OR = 1.98 (1.48-2.66). ≥ 1-para was associated with a decreased risk for AS(5 min) < 7, OR = 0.34 (0.25-0.47). In the univariate logistic regression analysis AS(5 min) < 7 was associated with tertiary level care, OR = 1.48 (1.17-1.87); however, in the multivariate analysis there was no significant difference.

CONCLUSION

A number of partially preventable risk factors were identified, preterm birth being the most evident. Further, no significant difference between the two hospital levels regarding the risk for low Apgar scores was detected.

Antenatal steroids and risk of bronchopulmonary dysplasia: a lack of effect or a case of over-adjustment?

Although antenatal steroids reduce risk factors for bronchopulmonary dysplasia (BPD) in preterm infants, their effect on BPD is conflicting. We hypothesised that the lack of protective effect found in some studies could derive from over-adjustment during analysis, caused by controlling for factors intermediate in the causal pathway between treatment and outcome. We prospectively studied a cohort of infants 23-32 weeks gestation <1500 g, admitted to 10 tertiary-level neonatal units in Lombardy (Italy) in 1999-2002; 1118 neonates out of 1314 survived to 36 weeks; 15.9% developed BPD (oxygen requirement at 36 weeks); 82% were treated with steroids. In univariable analysis, steroids were not significantly protective against BPD; some intermediate factors (mechanical ventilation, greater severity of illness as measured by Clinical Risk Index for Babies score, patent ductus arteriosus) were significantly positively associated with (i.e. were risk factors for) BPD (OR = 11.0, 1.55, 4.42, respectively, all P < 0.001), and negatively associated with (i.e. prevented by) steroids (OR = 0.58, 0.92, and 0.58, respectively, all P < 0.01). In multiple logistic regression models using propensity scores, without the above-mentioned intermediate risk factors, steroid-treated infants had a lower risk of BPD (OR 0.59 [95% CI 0.36, 0.97], P = 0.036); male sex (OR = 2.08), late-onset sepsis (OR = 4.26), and birthweight (OR = 0.63 for 100 g increase) were also associated with BPD, all P < 0.001. When intermediate risk factors for BPD were also added to the model, the effect of steroids disappeared; ventilation (OR = 3.03), increased illness severity (OR = 1.11), and patent ductus arteriosus (OR = 1.90) were significant risk factors. This study suggests that including variables that are potential mediators in the causal chain can obscure the ability to detect a protective effect of treatment. We observed such a phenomenon in our analyses of the relationship between antenatal steroids and BPD, suggesting that steroid effect is partly mediated through a reduction in the classical risk factors.

Is there an association between low birth weight and caries in the primary dentition?

OBJECTIVES

An association between low birth weight and caries in the primary dentition has been suggested but not demonstrated. This study analyzed this association using data from a probability sample of US children 2-6 years of age.

METHODS

Data from the Third National Health and Nutrition Examination Survey (NHANES III) were used. Variables included decayed and filled primary surfaces (dfs), birth weight, gestational age, and Apgar score (a surrogate measure of fetal well-being); maternal age, education, income; number of previous births, marital status, the existence of pregnancy complications, and cigarette smoking during the pregnancy. Data were analyzed using SUDAAN 8.0.2.

RESULTS

Bivariate Poisson regression showed that children of mothers who were unmarried (incidence density ratio, IDR = 3.28), with less education (IDR = 1.43), who were 17 years of age or younger at birth (IDR = 1.51), and had 2 or fewer prenatal visits (IDR = 1.65) had a significantly ( p <0.05) greater risk of caries than the reference groups. Children of mothers with pregnancy-related hypertension (IDR = 0.14) had less than 20% the risk of caries than the reference group. Blacks (IDR = 1.37) and Mexican-Americans (IDR = 2.38) had greater risk of caries than whites, and children of low (IDR = 2.57) and middle income (IDR = 2.00) level families had higher caries risks than those of upper income families. Multivariate Poisson regression found only race-ethnicity, age, and income level to be statistically significant.

CONCLUSIONS

This study did not support the association between low birth weight and caries of the primary dentition.

Early Infant Morbidity in the City of São Paulo, Brazil

BACKGROUND: Early infant morbidities may produce adverse outcomes in subsequent life. A low Apgar score is a convenient measure of early infant morbidity. We study determinants of early infant morbidity (sex, plurality, mode of delivery, prior losses, gestational age, prenatal care and birth weight, parity and maternal age, race, maternal education and community development) for the 1998-birth cohort, City of São Paulo, Brazil. METHODS: This study identified all deliveries that took place in the City of São Paulo during 1998. Information was extracted from 209,628 birth records. We used multivariate logistic regression to assess the effect of each independent variable on Apgar score less than seven at one minute and Apgar score less than seven at five minutes. RESULTS: Low birth weight, prematurity and community development were found to be strong predictors of morbidity. Maternal education showed strong negative correlation with both Apgar scores. The negative correlations between maternal schooling and Apgar scores were observed after prenatal care, parity and maternal age were included in the model. Unmeasured proximate factors may thus be the true source of disparity between educational groups. Children of very young adolescent mothers had lower Apgar scores at one minute (but not at five minutes) than those born to mothers 15 to 19. Parity one or higher was associated with decreased odds of low Apgar scores. Cesarean section and operative delivery were associated with higher odds of early infant morbidity. CONCLUSION: Education may allow mothers to have better care in the peripartum period. More educated mothers may be more likely to recognize certain morbidities through the pregnancy period and the monitoring of such morbidities yields better infant outcomes. Also, having less than seven prenatal care visits was found to predict early infant morbidity and one way to increase the use of such services is to focus on aspects of care that may lead to easier accessibility and continuity of prenatal care. Physicians should inform mothers about the risks associated with high number of children for a next infant and also about the risks for the infant associated with unnecessary cesarean sections. Special attention should be paid to adolescent mothers, since much of their increased risk is likely to be minimized by counseling.