Assessment of Risk Factors for Low Birth Weight Deliveries

Long-Acting β2-Agonists and Risk of Hypertensive Disorders of Pregnancy: A Cohort Study

BACKGROUND

Maternal asthma has been found to be associated with an increased risk of hypertensive disorders of pregnancy (HDP), that is, gestational hypertension, preeclampsia, and eclampsia. There is limited data, however, regarding the relationship between the use of long-acting beta-agonists (LABAs) during pregnancy and these outcomes.

OBJECTIVE

To investigate whether exposure to a LABA in addition to an inhaled corticosteroid increases the risk of HDP or preeclampsia/eclampsia, as compared with nonexposure to LABAs, in pregnant women with asthma.

METHODS

A cohort of 8,936 pregnancies in women with asthma who delivered between 1998 and 2010 was reconstructed using Quebec (Canada) health administrative databases. Cox proportional hazard regression models, adjusted for potential confounders, were used for statistical analyses. The primary exposure was LABA use (yes/no) measured on the first day of the 20th week of pregnancy. HDP were identified on the basis of recorded diagnoses and on prescriptions of antihypertensive drugs filled on or after the first day of week 20 of gestation.

RESULTS

There were 567 (6.3%) cases of HDP and 256 (2.9%) cases of preeclampsia/eclampsia in the cohort, and the rates of both disorders were similar in women exposed or not exposed to LABAs. LABA use was not associated with increased risks of HDP (adjusted hazard ratio, 0.96; 95% CI, 0.69-1.33) or preeclampsia/eclampsia (adjusted hazard ratio, 0.89; 95% CI, 0.53-1.50).

CONCLUSIONS

The results of this study provide evidence suggesting the safety of LABAs for the treatment of asthma in pregnancy, in terms of the risks of HDP and preeclampsia/eclampsia.

Breastfeeding throughout pregnancy in Turkish women

INTRODUCTION

Around the world, as well as in Turkey, women breastfeed their infants as long as possible. There is, however, a strong cultural taboo against continuing breastfeeding while having a new pregnancy. The aim of this study was to evaluate the outcome of pregnancies occurring during the lactation period and to determine whether lactation throughout the pregnancy had any adverse effects. This is the first study in Turkey to provide data on the association between the practice of lactation throughout pregnancy and outcome.

SUBJECTS AND METHODS

One hundred sixty-five multiparous women with singleton pregnancies who were ≥ 18 years of age, breastfeeding the previous child, and did not have systemic disease were included. Forty-five of the 165 pregnant women continued lactating, whereas 120 did not. We compared weight gain during pregnancy, hemoglobin level alterations, pregnancy complications, neonatal weight, and Apgar scores between the two groups.

RESULTS

Lactating pregnant women gained less weight than the nonlactating group, and the decreased level of hemoglobin during pregnancy was significant in the lactating group. Between the two groups, there was no statistically significant difference in hyperemesis gravidarum, threatened abortion, preeclampsia, premature labor and birth, neonatal weight, or Apgar scores.

CONCLUSIONS

Breastfeeding during pregnancy is not harmful, and health professionals should not advise weaning if overlapping occurs and should observe mother, infant, and fetus closely for negative effects, and if a negative effect occurs they should take precautions.

A case-control study to examine the association between breastfeeding during late pregnancy and risk of a small-for-gestational-age birth in Lima, Peru

Excessive demands on maternal nutritional status may be a risk factor for poor birth outcomes. This study examined the association between breastfeeding during late pregnancy (≥ 28 weeks) and the risk of having a small-for-gestational-age (SGA) newborn, using a matched case-control design (78 SGA cases: birthweight <10th percentile for gestational age; 150 non-SGA controls: 50th percentile <birthweight <90th percentile for gestational age). Between March 2006 and April 2007, project midwives visited daily three government hospitals in Lima, Peru and identified cases and matched controls based on hospital, gestational age, and inter-gestational period. Mothers were interviewed and clinical chart extractions were completed. Factors associated with risk of SGA were assessed by their adjusted odds ratios (aOR) from conditional logistic regression. Exposure to an overlap of breastfeeding during late pregnancy was not associated with an increased risk of having a SGA newborn [aOR=0.58, 95% confidence interval (CI): 0.10-3.30]. However, increased risk was associated with having a previous low-birthweight birth (aOR=6.53; 95% CI: 1.43-29.70) and a low intake of animal source foods (<25th percentile; aOR=2.26; 95% CI: 1.01-5.04), and tended to be associated with being short (<150 cm; aOR=2.05; 95% CI: 0.92-4.54). This study found no evidence to support the hypothesis that breastfeeding during late pregnancy increases the risk for SGA; however, studies with greater statistical power are needed to definitively examine this possible association and clarify whether there are other risks to the new baby, the toddler and the pregnant woman.

Birth outcomes and risk factors in adolescent pregnancies: results of a Taiwanese national survey

BACKGROUND

This study explores birth outcomes and determinants in adolescent pregnancies, using subjects drawn from the Taiwan Birth Cohort Study (TBCS) from 2005.

METHODS

Through completed interviews and surveys with mothers or other family members, differences in birth outcomes and personal, pregnancy and social profiles of mothers were analyzed.

RESULTS

A total of 533 adolescent mothers (<20 years old) and 9347 adult mothers (20-34 years old) were included in our study. There was a significantly higher incidence of low birthweight (LBW) (<2500 g, 10.2% vs 5.6%) and premature birth (<37 weeks, 14.8% vs 8.6%) in the adolescent group. When adjusted for covariates in the multiple-variable model, youth remained a risk factor for LBW (OR = 1.50, 95%CI 1.09, 2.07) and premature delivery (OR = 1.42, 95%CI 1.07, 1.89). Age, prenatal care and weight gain during pregnancy are important predictors of LBW and premature birth.

CONCLUSION

Adolescent pregnancy carries a high-risk of LBW and premature birth. Inadequate prenatal care and weight gain during pregnancy are contributing factors that could be improved through strategies of health education, family support and case management.

[Maternal smoking during pregnancy and socioeconomic factors as predictors of low birth weight in term pregnancies in Nis]

BACKGROUND/AIM

Low birth weight (LBW) is a result of preterm birth or intrauterine growth retardation, and in both cases is the strongest single factor associated with perinatal and neonatal mortality. It is considered that socioeconomic factors, as well as mothers bad habits, play the most significant role in the development of LBW, which explains notable number of researches focused on this particular problem. The aim of this study was to characterize socioeconomic factors, as well as smoking habits of the mothers, and their connection with LBW.

METHODS

The questionnaire was carried out among mothers of 2 years old children (n = 956), born after 37 gestational weeks. The characteristics of mothers who had children with LBW, defined as < 2,500 g, (n = 50), were matched with the characteristices of mothers who had children > or = 2,500 g, (n = 906). For defining risk factors, and protective factors as well, we used univariant and multivariant logistic modeles.

RESULTS

As significant risk factors for LBW in an univariant model we had education level of the mothers, smoking during pregnancy, smoking before pregnancy, the number of daily cigarettes, the number of cigarettes used during pregnancy, paternal earnings and socioeconomic factors. In a multivariant model the most significant factors were socioeconomic factors, education level of the mothers, paternal earnings and mothers smoking during pregnancy.

CONCLUSION

Smoking during pregnancy and socioeconomic factors have great influence on LBW. Future studies should be carried out in different social groups, with the intention to define their influence on LBW and reproduction, as well. This should be the proper way of adequate health breeding planning for giving up smoking, the prevention of bad habits and melioration of mothers and children health, as the most vulnerable population.

Pregnancy outcomes related to gestational weight gain in women defined by their body mass index, parity, height, and smoking status

BACKGROUND

Recommendations for gestational weight gain (GWG) account for a woman's prepregnancy body mass index (BMI), but other factors may be important.

OBJECTIVES

The objectives were to investigate whether, within BMI categories, the GWG with the lowest risks to mother and infant varied with parity and to describe these risks in short (<160 cm), young (<20 y), and smoking women.

DESIGN

Of 27,030 primiparous and 31,407 multiparous women with term births within the Danish National Birth Cohort, self-reported GWG was divided into 6 categories (<5, 5-9, 10-15, 16-19, 20-24, and > or =25 kg). Population-based registers provided information about birth outcomes. GWG-specific absolute adjusted risks for emergency cesarean delivery, birth of a small-for-gestational-age (SGA) or large-for-gestational-age (LGA) infant, and postpartum (6 mo) weight retention (PPWR) were compared across different types of women.

RESULTS

The risk of SGA decreased with increasing GWG in both parity groups, but SGA risk <10% was reached at 2-3 GWG categories lower in multiparae than in primiparae. An excess risk of LGA was present only in obese primiparae and multiparae, but the PPWR risk increased with increasing GWG irrespective of BMI and parity. Young primiparae had better outcomes than other primiparae. Short women had a higher risk of emergency cesarean delivery that varied minimally with GWG. Smokers had a higher SGA risk and had a PPWR risk similar to that of nonsmokers.

CONCLUSIONS

The tradeoff in risk between mother and infant is reached at lower GWG in multiparae than in primiparae; therefore, a lower GWG may be needed among multiparae. Differential guidelines seem unnecessary for short or young women or smokers.

Social stressors and strengths as predictors of infant birth weight in low-income African American women

BACKGROUND

Perinatal racial disparities remain an elusive problem in the United States. African American women experience the highest rate of low-birth-weight deliveries. Understanding the factors contributing to infant birth weight is crucial to unraveling existing perinatal racial disparities.

OBJECTIVE

The aim of this study was to broaden knowledge of predictors of infant birth weight in African American people by examining stress and resource factors not explored routinely in perinatal research along with other known correlates of birth weight.

METHODS

A total of 119 pregnant African American women participated in this prospective study. Social stressors included discrimination and trauma exposure. Personal resources included spirituality and social support. Data on socioeconomic status, health behaviors, and medical conditions were collected.

RESULTS

On average, the infants weighed 3,194 +/- 660 g at birth. Overall, 14% were born with birth weights less than 2,500 g. Tobacco use, number of prenatal visits, and discrimination due to age and physical disability were significant predictors of infant birth weight (R2 = .25; p >or= .001). Factors such as spirituality and social support were not associated with birth weight. Other variables traditionally associated with birth weight did not contribute to the model in this sample.

CONCLUSION

These findings provide further evidence that tobacco use, number of prenatal visits, and discrimination adversely affects birth outcomes. By continuing to explore the social and personal experiences of African American women, important insights can be gained on factors that contribute to the pervasive racial disparities in perinatal health and contribute to interventions to improve the quality of healthcare for all women.

Matching risk and resources in high-risk pregnancies

OBJECTIVE

To evaluate the joint impact of pregnancy risk and the timing of referral of high-risk pregnancies from obstetricians to maternal fetal medicine (MFM) sub-specialists on gestational age (GA) at delivery.

METHODS

For the period 1992-2002, 2567 consecutive deliveries from pregnancies of at least 23 weeks gestational age (GA) from a community-level sub-specialty perinatal center were studied. A multiple regression model was developed specifying the impact of various risk factors and referral timing.

RESULTS

Prior pregnancy risk was inversely related to GA at birth. Referral timing, operationalized as a continuous variable, did not have a significant additive impact on GA at birth, but several dummy-variable interaction effects combining risk factors and referral before 20 weeks as a dichotomy were significant.

CONCLUSION

There are identifiable risks that occur either before the pregnancy or early into it that should lead to early referral to a sub-specialist because of their impact on GA at birth. Early referral is an important tactic in a larger preterm prevention strategy, but it needs to be embedded in a broader maternal-fetal health initiative in which both generalists and sub-specialists play important roles.

Influence of maternal and social factors as predictors of low birth weight in Italy

Background

The purpose of this study is to provide insight into the determinants of low birth weight (LBW) in Italy.

Methods

The study was carried out in a non-teaching hospital in Catanzaro (Italy). All LBW and very LBW newborns (200) were included in the study and a random sample of 400 newborns weighing ≥ 2500 g was selected. Data were collected from the delivery certificates during one year. Smoking activity of mother and familiar and/or social support during pregnancy was gathered through telephone interviews.

Results

Overall annual LBW rate was 11.8%. Among LBW newborn there were 125 preterm and 75 term. Younger mothers, those who smoked during pregnancy, and had fewer prenatal care visits were more likely to deliver a LBW child; moreover, preterm newborns, delivered by caesarean section, and twin or multiple birth were significantly more likely to have a LBW. The comparison of very LBW (<1500 g) to LBW newborns showed that a very LBW was significantly more likely in newborns delivered by less educated mothers, those who work outside the home, live in smaller towns, and had less echographies; moreover, as expected, very LBW newborns were more likely to be preterm.

Conclusion

Several modifiable factors affect the risk of LBW, even when universal access to health care is freely available, but socio-economic status appears to correlate only to very LBW.

Factors predicting birth weight in a low-risk sample: the role of modifiable pregnancy health behaviors

OBJECTIVES

The purpose of the present study was to examine background and modifiable pregnancy health behavior factors predicting infant birthweight in an economically and educationally disadvantaged sample with low medical risk.

METHODS

PARTICIPANTS were recruited from a family practice center in rural Appalachia.

PARTICIPANTS

Over 220, predominantly Caucasian and lower SES women with low risk pregnancies were included in the sample. Data were collected through systematic chart review. Half of the women smoked during pregnancy and over 10% gave birth to low birth weight (LBW; < 2500 g) babies.

RESULTS

Compared with those who gave birth to normal weight newborns, women with LBW babies had more miscarriages, but did not differ significantly on other background factors. Women who delivered LBW babies gained less weight during pregnancy and were more likely to smoke than remaining women. After control for background factors, modifiable pregnancy health behavior factors (weight gain, prenatal care, smoking, alcohol and substance use) accounted for over 11% of birth weight variance, with nearly 7% attributable solely to smoking.

CONCLUSIONS

Pregnancy smoking was the strongest behavioral predictor of LBW in this economically and educationally disadvantaged rural sample, suggesting that efforts to reduce LBW in similar populations should include targeting pregnancy smoking.