Department of Nursing, West China Second University Hospital, Sichuan University/West China School of Nursing, Sichuan University, No. 20 Third Section, Renmin South Road, Chengdu, Sichuan Province, 610041, China.
Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, Sichuan, China.
Int Breastfeed J. 2024 Aug 22;19(1):59. doi: 10.1186/s13006-024-00666-5.
Breastfeeding has many benefits for mothers and infants. Lactogenesis II is one of the key steps in the implementation of breastfeeding. If lactogenesis II occurs more than 72 h after delivery, it is termed delayed onset of lactation (DOL). DOL is associated with decreased milk production, shortened breastfeeding time, and pathological neonatal weight loss. A comprehensive summary of the incidence and factors influencing DOL is needed to provide a basis for improving breastfeeding practices and health outcomes.
Studies on the incidence and factors influencing DOL were retrieved from 13 Chinese and English databases (PubMed, Embase, Web of Science, Cochrane Library, CINAHL, etc.) from database inception to August 2023. Two researchers independently conducted the study screening, data extraction and quality evaluation. Stata 16.0 SE software was used for data analysis, and sensitivity analysis and publication bias tests were also performed. The qualitative description method was used to analyse studies that could not be combined quantitatively.
A total of 35 studies involving 19,176 parturients, including 4,922 who had DOL, were included. The mean Newcastle‒Ottawa scale score of the included studies was ≥ 6, indicating that the quality was relatively high. Finally, the incidence of DOL was 30%, and 13 factors influencing DOL with robust results and no publication bias were obtained: prepregnancy body mass index (overweight or obesity), gestational diabetes, gestational hypertension, thyroid disease during pregnancy, serum albumin levels (< 35 g/L), parity, (unscheduled) caesarean section, caesarean section history, daily sleep duration, gestational age, birth weight (< 2.5 kg), breastfeeding guidance and daily breastfeeding frequency. However, there were still six influencing factors with undetermined associations: age, gestational weight gain, birth weight (≥ 4 kg), anxiety, time of first breastfeeding session (maternal separation) and breast massage or treatment.
The incidence of DOL is high. Clinicians should pay attention to parturients at high risk of DOL and formulate targeted prevention strategies according to the influencing factors to reduce the occurrence of DOL and promote better maternal and infant outcomes.
PROSPERO (ID: CRD42023458786), September 10, 2023.
母乳喂养对母婴都有诸多益处。泌乳二期是实施母乳喂养的关键步骤之一。如果泌乳二期在分娩后 72 小时以上才出现，则称为泌乳启动延迟（DOL）。DOL 与产奶量减少、母乳喂养时间缩短和新生儿病理性体重下降有关。因此，需要综合总结 DOL 的发生率和影响因素，为改善母乳喂养实践和健康结局提供依据。
从建库至 2023 年 8 月，检索 13 个中英文数据库（PubMed、Embase、Web of Science、Cochrane Library、CINAHL 等）中关于 DOL 发生率及影响因素的研究。由 2 位研究者独立进行研究筛选、数据提取和质量评价。采用 Stata 16.0 SE 软件进行数据分析，并进行敏感性分析和发表偏倚检验。对于无法进行定量合并的研究，采用定性描述方法进行分析。
共纳入 35 项研究，涉及 19176 名产妇，其中 4922 例发生 DOL。纳入研究的 Newcastle-Ottawa 量表评分均值≥6，表明质量较高。最终 DOL 发生率为 30%，得到 13 个具有稳健结果且无发表偏倚的影响 DOL 的因素：孕前体质量指数（超重或肥胖）、妊娠期糖尿病、妊娠期高血压、妊娠期间甲状腺疾病、血清白蛋白水平（<35 g/L）、产次、（计划外）剖宫产、剖宫产史、每日睡眠时间、胎龄、出生体重（<2.5 kg）、母乳喂养指导和每日母乳喂养次数。但仍有 6 个影响因素关联不确定：年龄、妊娠期体重增加、出生体重（≥4 kg）、焦虑、首次母乳喂养时间（母婴分离）和乳房按摩或治疗。
DOL 的发生率较高。临床医生应关注有发生 DOL 风险的产妇，并根据影响因素制定针对性的预防策略，以减少 DOL 的发生，促进母婴结局改善。
PROSPERO（ID：CRD42023458786），2023 年 9 月 10 日。
