Prevalence and risk factors of delayed onset lactogenesis II in China: a systematic review and meta-analysis

Figures & data

Figure 1. Flow chart of study selection process.

Table 1. Characteristics of included studies.

Study	sample size	Number of females with DOL	Period	Region	Study design	Influencing factors	NOS
Dong 2022	622	241	2020.11–2021.1	Jining	Cross sectional	Maternal age > 35 years, Primiparous women, Maternal overweight/obesity	6
Li 2022	300	107	2020.2–2021.5	Binzhou	Cohort	Maternal overweight/obesity	9
Huang 2021	1188	312	2020.1–12	Shanghai	Cohort	Maternal age > 35 years, Breastfeeding initiation > 30 min after birth, Primiparous women,Cesarean section,Anxiety,Depression	8
Xie 2021	229	97	2019.5–10	Zhejiang	Cohort	Maternal age > 35 years,	9
Pan 2020	80	22	2016.6–2019.6	Changzhou	Case-control	Maternal age > 35 years,Primiparous women,the frequency of breastfeeding was >2 times per day at 24–48 h after delivery	7
Ding 2020	340	107	2018.1–2019.1	Anhui	Case-control	Primiparous women,Maternal overweight/obesity	8
Luo 2020	388	99	2015.1–2018.12	Foshan	Case-control	Maternal age > 35 years, Maternal overweight/obesity,Anxiety, Depression	7
Liao 2018	394	135	2015.1–2017.1	Neijiang	Case-control	Maternal age > 35 years,Maternal overweight/obesity	9
Teng 2018	286	112	2017.1–9	Wenzhou	Case-control	Primiparous women, Anxiety, Depression	8
Luan 2018	100	36	2016.2–12	Binzhou	Cohort	Breastfeeding initiation > 30 min after birth	9
Si 2017	284	96	2016.4–9	Nanjing	Case-control	Maternal age > 35 years, Primiparous women	9
Jiang 2016	11178	3388	2013.1–12	Nationwide	Cross sectional	Breastfeeding initiation > 30 min after birth, Cesarean section	6
Xue 2015	204	58	2013.9–2014.5	Guangzhou	Case-control	Primiparous women,Cesarean section,the frequency of breastfeeding was >2 times per day at 24–48 h after delivery	8
Zhu 2010	2017	191	2008.1–9	Hefei	Cohort	Cesarean section	9

Figure 2. Forest plot for the prevalence of delayed onset lactogenesis II.

Figure 3. Forest plot for subgroup analysis of China region.

Figure 4. Forest plot for subgroup analysis of study type.

Table 2. Pooled influencing factors of delayed onset lactogenesis II.

Influencing factors	NO.of study	Heterogeneity test		Meta model	Meta results
		p value	I^2(%)		Effect estimate	95% confidence interval	p value
Infant-related factors
Breastfeeding initiation > 30 min after birth	3	<.001	92.5	Random	1.31	1.07–1.59	.009
The frequency of breastfeeding was >2 times per day at 24–48 h after delivery	2	.465	0	Fixed	0.41	0.25–0.66	<.001
Maternal-related factors
Maternal age > 35 years	6	.503	0	Fixed	2.19	1.81–2.65	<.001
Primiparous women	7	.884	0	Fixed	2.38	1.99–2.86	<.001
Maternal overweight/obesity	5	<.001	87.7	Random	2.22	1.28–3.33	.004
Cesarean section	4	.288	20.3	Fixed	1.33	1.21–1.47	<.001
Anxiety	3	.926	0	Fixed	3.23	2.17–4.82	<.001
Depression	3	.880	0	Fixed	3.21	2.19–4.70	<.001
Gestational hypertension	4	.325	13.5	Fixed	3.43	2.54–4.61	<.001

Data availability statement

No additional data available