Incidence and factors influencing delayed onset of lactation: a systematic review and meta-analysis.

Yijuan Peng, Ke Zhuang, Yan Huang

Journal: International breastfeeding journal 2024;19(1):59

PMID: 39175092

Free Full Text on BioMed Central View on PubMed

Plain Language Summary

Delayed onset of lactation (DOL) is a common issue that can affect breastfeeding success and infant nutrition. Understanding the incidence and factors contributing to DOL is crucial for developing effective interventions to support new mothers. The primary aim of this study was to determine the incidence of delayed onset of lactation and identify the factors that influence its occurrence. This study is a systematic review and meta-analysis of thirty-five studies. Results showed that the incidence of DOL was 30%, and the factors influencing DOL may include pre-pregnancy body mass index (overweight or obesity), gestational diabetes mellitus, hypertensive disorders of pregnancy, 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, the relationships between age, gestational weight gain, birth weight (≥4kg), anxiety, time of first breastfeeding session (maternal separation) and breast massage or treatment and DOL remain unknown. Authors concluded that findings underscore the importance of targeted support and interventions for at-risk mothers to promote timely lactation onset and successful breastfeeding.

Abstract

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

TRIAL REGISTRATION

PROSPERO (ID: CRD42023458786), September 10, 2023.

Address: 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.; 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. [email protected].; Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, Sichuan, China. [email protected].

DOI: 10.1186/s13006-024-00666-5