Prenatal medical risk describes physical health issues or biological factors that predate or arise during pregnancy which heighten the risk of adverse outcomes, and often warrant specialized obstetric care. The influence of the nature and magnitude of prenatal risk on breastfeeding outcomes remains poorly understood. The objective of this study was to determine the association between prenatal medical risk and breastfeeding initiation and duration up to 1 year postpartum. We analysed a subset of data from the All Our Families longitudinal cohort (n = 2706) of women in Calgary, Canada who delivered a liveborn infant between 2008 and 2010. Data were collected from self-report questionnaires and medical records. Women with complete data on prenatal medical risk factors and breastfeeding outcomes were included in this analysis. Prenatal medical risk was operationalized as one integer score of risk severity and four binary risk types capturing pre-pregnancy characteristics, past obstetric problems, current obstetric problems, and substance use. Outcomes were breastfeeding initiation defined as the infant ever receiving breast milk, and duration operationalized as still breastfeeding at 4 months, at 12 months, and time to breastfeeding cessation in weeks. We used logistic regression and Cox regression with right censoring at 52 weeks or attrition to calculate odds ratios (OR) and hazard ratios (HR), respectively, adjusting for sociodemographic vulnerability, parity, mode of delivery, and gestational age. Prenatal medical risk severity and type were not significantly associated with breastfeeding initiation, with the exception of pre-pregnancy risk type (OR 0.45; 95% CI 0.26, 0.77). Risk severity was associated with lower odds of breastfeeding to 4 months (OR 0.94; 95% CI 0.90, 0.99), 12 months (OR 0.93; 95% CI 0.87, 0.98), and earlier breastfeeding cessation (HR 1.05; 95% CI 1.02, 1.08). Associations with shorter breastfeeding length across the first postpartum year were observed for pre-pregnancy, current obstetric, and substance use risk types, but not past obstetric problems. Prenatal medical risk is associated with shortened duration of breastfeeding. Women with prenatal medical risk may benefit from the proactive arrangement of lactation support before and following delivery to promote continued breastfeeding.

中文翻译：

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在我们所有家庭社区出生队列中，产前医疗风险与长达 12 个月的母乳喂养结果的关联

产前医疗风险描述了怀孕前或怀孕期间出现的身体健康问题或生物因素，这些问题会增加不良后果的风险，并且通常需要专门的产科护理。产前风险的性质和程度对母乳喂养结果的影响仍然知之甚少。本研究的目的是确定产前医疗风险与母乳喂养开始和长达产后 1 年的持续时间之间的关联。我们分析了 2008 年至 2010 年间分娩活产婴儿的加拿大卡尔加里妇女的所有家庭纵向队列 (n = 2706) 的子集数据。数据来自自我报告问卷和医疗记录。具有完整的产前医疗风险因素和母乳喂养结果数据的女性也被纳入该分析。产前医疗风险被操作为风险严重性的一个整数分数和四个二元风险类型，包括孕前特征、过去的产科问题、当前的产科问题和物质使用。结果是开始母乳喂养，定义为婴儿曾接受母乳喂养，持续时间为 4 个月、12 个月时仍然母乳喂养，以及停止母乳喂养的时间为数周。我们使用逻辑回归和 Cox 回归，在 52 周或自然减员时进行右删失，分别计算比值比 (OR) 和风险比 (HR)，调整社会人口脆弱性、胎次、分娩方式和胎龄。产前医疗风险的严重程度和类型与开始母乳喂养没有显着关联，但孕前风险类型除外（OR 0.45；95% CI 0. 26, 0.77)。风险严重程度与母乳喂养至 4 个月 (OR 0.94; 95% CI 0.90, 0.99)、12 个月 (OR 0.93; 95% CI 0.87, 0.98) 和更早停止母乳喂养的几率 (HR 1.05; 95% CI 1.02) 相关, 1.08)。在孕前、当前的产科和物质使用风险类型中观察到与产后第一年较短的母乳喂养时间相关联，但未观察到过去的产科问题。产前医疗风险与母乳喂养时间的缩短有关。有产前医疗风险的妇女可能会受益于在分娩前后主动安排哺乳支持以促进继续母乳喂养。95% 置信区间 1.02, 1.08)。在孕前、当前的产科和物质使用风险类型中观察到与产后第一年较短的母乳喂养时间相关联，但未观察到过去的产科问题。产前医疗风险与母乳喂养时间的缩短有关。有产前医疗风险的妇女可能会受益于在分娩前后主动安排哺乳支持以促进继续母乳喂养。95% 置信区间 1.02, 1.08)。在孕前、当前的产科和物质使用风险类型中观察到与产后第一年较短的母乳喂养时间相关联，但未观察到过去的产科问题。产前医疗风险与母乳喂养时间的缩短有关。有产前医疗风险的妇女可能会受益于在分娩前后主动安排哺乳支持以促进继续母乳喂养。