Pregnancy complications and risk of preterm birth according to maternal age: A population-based study of delivery hospitalizations in Alberta.

INTRODUCTION: Pregnancy-related medical complications are associated with a 2- to 5-fold increased risk of preterm birth (PTB), but the nature of this etiologic relation in context with maternal factors remains poorly understood. Previous studies have generally treated maternal age as a confounder but overlooked its potential as an effect modifier, whereby the magnitude of the effect of complications on PTB could differ significantly across age groups. We investigated whether advanced maternal age (≥35 years) modified the association between pregnancy complications and PTB, and compared population-attributable fractions of PTB from complications in women older vs younger than 35 years. MATERIAL AND METHODS: We analyzed population-based, cross-sectional data from the Alberta Discharge Abstract Database for women aged 18-50 years with singleton live births in hospital between 2014 and 2017 (n = 152 246). Complications were preeclampsia, gestational diabetes, and placental disorders identified using diagnostic codes. Outcomes were spontaneous (sPTB) or iatrogenic (iPTB) PTB before 37 weeks of gestation. We estimated risk ratios and risk differences using modified Poisson and log binomial regression, respectively, adjusting for confounders (pregnancy history, comorbidities). Population-attributable fractions estimates were calculated from risk ratios. Age modification was tested using interaction terms and Z-tests. RESULTS: Prevalence of advanced maternal age was 19.2%. Pregnancy complications and s/iPTB were more common among women aged ≥35 years. Age modified the risk of PTB from preeclampsia only, with risk differences of 9.9% (95% CI 7.2%-12.6%) in older women vs 6.1% (95% CI 4.8%-7.4%) in younger women (P-interaction = 0.012) for sPTB, and 29.5% (95% CI 26.0%-33.1%) vs 20.8% (95% CI 18.9%-22.6%, P-interaction <0.001) for iPTB. Population-attributable fractions of s/iPTB types for all complications were consistently 2%-5% larger in women aged ≥35 years, and significantly larger for preeclampsia (sPTB: 5.1% vs 2.7%, P = 0.002; iPTB: 18.8% vs 14.0%, P < 0.001) and placental disorders (sPTB: 12.5% vs 8.7%, P < 0.001; iPTB: 13.2% vs 8.9%, P < 0.001). CONCLUSIONS: Of the pregnancy complications studied, advanced maternal age only modified the association between PTB and preeclampsia, such that older women with preeclampsia have a higher risk for s/iPTB than younger counterparts. Pregnancy complications contribute to a sizable proportion of PTBs in Alberta, especially among women aged ≥35 years. Findings may inform clinical risk assessment and population-level policy targeting PTB.

Maternal chronic disease and breastfeeding outcomes: a Canadian population-based study.

BACKGROUND: The prevalence of chronic disease in pregnant women has consistently risen over the past two decades. Substantial evidence demonstrates that maternal chronic disease is associated with adverse medical outcomes like preterm birth, but less research has characterized postpartum outcomes such as infant feeding practices. It is recommended that infants be exclusively breastfed from birth to 6 months given the numerous health benefits it provides. OBJECTIVE: To determine the association between maternal chronic disease and breastfeeding outcomes. METHODS: We analyzed cross-sectional self-report data from the 2015/2016 Canadian Community Health Survey, restricted to women who gave birth within 2 years of data collection (n = 2100, rounded). The exposure was professionally diagnosed chronic physical disease (e.g. diabetes, arthritis, heart disease). The outcomes were breastfeeding non-initiation and early cessation of breastfeeding before 6 months. Multivariable logistic regression modeling was used to estimate adjusted odds ratios (AOR) with 95% confidence intervals (CIs). Estimates were bootstrapped and weighted to represent the national population. RESULTS: Overall, 11.9% (95% CI 9.8-14.1) of women reported chronic disease, and were more likely to be single, be Canadian born, have low education, and be overweight/obese than women without chronic disease. The mean maternal age was approximately 30 years in both groups. Women with chronic disease had similar odds of breastfeeding non-initiation (AOR 0.96, 95% CI 0.54-1.71) and early cessation of any breastfeeding (AOR 1.40, 95% CI 0.82-2.40), but over twice the odds of early cessation of exclusive breastfeeding (AOR 2.48, 95% CI 1.49-4.12) compared to unaffected women. CONCLUSION: Mothers with chronic disease initiate and continue some form of breastfeeding to six months as often as their unaffected peers. However, they have substantially higher odds of ceasing exclusive breastfeeding before the recommended 6 months. Findings suggest a need to investigate the reasons for this disparity to ensure that appropriate breastfeeding support is available for women with chronic disease and their children.

Risk factors for cessation of breastfeeding prior to six months postpartum among a community sample of women in Calgary, Alberta.

OBJECTIVES: To describe the rates of breastfeeding initiation and breastfeeding for at least six months and identify risk factors for failing to breastfeed for six months among a community sample of mothers in Calgary, Alberta. METHODS: A cohort of women (n=1737) who participated in a longitudinal study of prenatal support and who could be contacted when their child was three-years-old (n=1147) were invited to participate in a follow-up telephone questionnaire. Of these 1147 women, 780 (69% participating rate) participated and provided breastfeeding data. Risk factors for early cessation of breastfeeding prior to six months were identified using bivariate and multivariable strategies. RESULTS: Of the 780 women, 95.6% initiated breastfeeding and 71.6% continued to breastfeed for at least six months. Risk factors identified for early cessation included younger maternal age, obesity prior to pregnancy, lower maternal education, working full-time or intending to within the first year, history of depression, depression or anxiety during pregnancy, poor social support, and smoking during pregnancy (all p<0.05). Multivariable analysis revealed that working full-time or intending to within the first year, lower maternal education, obesity prior to pregnancy and anxiety during pregnancy most increased a woman's risk of early cessation (all p<0.05). CONCLUSION: Nearly all mothers initiated breastfeeding and 70% continued to breastfeed for six months, although subgroups of women remained at an elevated risk of early cessation. Research to better understand breastfeeding decisions among women with the risk factors identified is needed to facilitate the development of more effective breastfeeding promotion strategies.

The effect of skin-to-skin care on postpartum depression among mothers of preterm or low birthweight infants: A systematic review and meta-analysis.

BACKGROUND: Mothers of preterm or low birthweight (LBW) infants are at two to three times greater risk of postpartum depression (PPD) than mothers of healthy infants, which may be partially due to mother-infant separation during hospitalization. Skin-to-skin care could protect against PPD among these vulnerable mothers. We examined the effect of skin-to-skin care on PPD among mothers of preterm or LBW infants through a systematic review and meta-analysis. METHODS: We searched six peer-reviewed databases for prospective studies of skin-to-skin interventions that took place in neonatal intensive care units (NICUs), used a validated PPD tool, and were published in English between 1979 and 2017. Data were standardized and pooled using Hedges method in a quality-weighted meta-analysis. RESULTS: Eight studies detailing seven interventions met inclusion criteria. Intervention characteristics varied with duration ranging from one week to over two months, skin-to-skin sessions ranging from 15 min to 1 h, and frequency ranging from thrice daily to thrice weekly. Five PPD tools were used predominantly as continuous measures. Meta-analysis demonstrated that skin-to-skin interventions were associated with a 1.04% reduction in standardized depression scores versus standard care (p < 0.001), though high heterogeneity was evident (I2 = 82.4%, p < 0.001). LIMITATIONS: Studies differed markedly with respect to design and intervention features, and were methodologically limited by using continuous depressive scores (not dichotomous PPD diagnoses) as the outcome. CONCLUSIONS: Skin-to-skin care has a small protective effect on maternal depressive scores, however the clinical relevance of this finding is arguably minimal. Additional well-designed studies are warranted to conclusively assess the effects of skin-to-skin on PPD.

National Analysis of Risk Assessment Content in Prenatal Records Across Canada.

Each Canadian province/territory has a distinct prenatal record form to guide maternity health care. Because there is no national oversight of these forms, little is known about how they compare regarding content on risk assessment for adverse perinatal outcomes. We cataloged and compared the risk factors that are captured on prenatal record forms across Canada. Nine out of 12 records included risk sections, with an average of 35 risk items. We identified 100 prenatal risk factors and categorized them as medical (73%), lifestyle (11%), psychosocial (11%), or personal (5%). Where present, clinical definitions for risk factors often varied. The substantial differences in risk assessment content in the prenatal record forms may contribute to differences in health care quality among provinces. The development of standardized national guidelines for prenatal risk assessment may be a valuable goal.

Administration of epidural labor analgesia is not associated with a decreased risk of postpartum depression in an urban Canadian population of mothers: a secondary analysis of prospective cohort data.

BACKGROUND: Postpartum depression (PPD) is a common complication of pregnancy, affecting approximately 13% of mothers internationally. Previous research has examined whether epidural analgesia used for pain control during labor and birth is associated with a lower risk of PPD, but reports conflicting results and may have suffered from methodological shortcomings. Our study aimed to prospectively assess whether epidural analgesia is associated with a lower risk of PPD (at either 6 weeks or 6 months postpartum) after attempting to adequately adjust for selection bias and confounding variables. METHODS: We conducted a secondary analysis of a prospective cohort of urban Canadian mothers who were recruited at birth in Calgary, Canada, in 2010, for a primary study on predictors of PPD. Mothers with full-term, singleton infants who did not require neonatal intensive care unit admission of >24 hours were included, and filled out questionnaires at birth, 6 weeks and 6 months postpartum including demographics, birth data, maternal and infant physical health, lifestyle, breastfeeding and maternal mental health. Descriptive statistics were calculated for participant characteristics and to identify potential confounder variables. Multivariable logistic regression analysis was conducted to assess whether epidural analgesia is associated with PPD after controlling for available confounding variables. RESULTS: Our study included 206 mothers who had vaginal deliveries and were free of depression at delivery. We found an incidence of PPD of 13.3% (n=27) and no statistically significant association between epidural use and PPD, regardless of adjustment for potential confounding variables (unadjusted odds ratio [OR] 0.86, 95% confidence interval [CI] 0.69-1.22; adjusted OR (for body mass index 1.04, 95% CI 0.40-2.77). CONCLUSION: We did not observe a significant association between epidural use and PPD. While the CIs are wide, we do not believe that this masks a clinically relevant association, and as such, the risks and benefits of epidural analgesia communicated to women during labor and delivery should not be modified.