Wang et al.

BMC Pregnancy and Childbirth (2021) 21:248

https://doi.org/10.1186/s12884-021-03714-8

RESEARCH ARTICLE Open Access

The effectiveness of the laid-back position

on lactation-related nipple problems and
comfort: a meta-analysis
Zhi Wang1, Qiuyue Liu2, Lihua Min3* and Xiaorong Mao3*

Abstract
Background: The importance of breastfeeding for maternal and child health is agreed upon worldwide. However,
lactation-related nipple problems are common and are important factors affecting breastfeeding. Multiple studies
recommended laid-back breastfeeding, but they are of various levels of quality, and the results are inconclusive.
Methods: We systematically searched the following twelve databases from inception to January 28,2020: Cochrane
Library, EMBASE, Medline, Ovid, PubMed, Web of Science, CINAHL, Scopus, Chinese National Knowledge
Infrastructure (CNKI), China Biology Medicine disc (CBM), WanFang, and VIP. All studies regarding laid-back
breastfeeding or biological nurturing were considered, regardless of whether they were randomized controlled
trials. Two trained investigators independently evaluated the quality of the selected articles and screened the data.
All the data were analysed separately using Review Manager Version 5.3 and STATA/SE Version 15.1.
Results: A total of 12 studies involving 1936 groups of postpartum women and their newborns were included. The
results of the meta-analysis showed that nipple pain (RR = 0.24; 95% CI 0.14, 0.40; p < 0.00001), nipple trauma (RR =
0.47; 95% CI 0.29, 0.75; p = 0.002) and correct latching position (RR = 1.22; 95% CI 1.11, 1.33; p < 0.0001) in the
experimental groups were all better than those of the control groups, and the differences were statistically
significant (p < 0.05), which indicates that the laid-back position has a positive effect on maternal breastfeeding.
However, the results of position comfort showed that there was no statistical significance between the two groups
(ES = 0.09; 95% CI -0.63, 0.81; p = 0.798).
Conclusion: Compared with traditional breastfeeding positions, the laid-back position has been proven to be
related to a decreased incidence of nipple pain and nipple trauma and is seemingly conducive to the use of the
correct latching position. It is suggested that the laid-back position is helpful in solving lactation-related nipple
problems and can be recommended as a position for breastfeeding. However, no significant difference in position
comfort was found between the two groups based on the current evidence, and further studies are still needed to
validate these results due to the limitations of the included studies.
Keywords: Breastfeeding, Biological nurturing, Laid-back breastfeeding, Meta-analysis

* Correspondence: 915805395@qq.com; 449696256@qq.com

3
Department of Nursing, Sichuan Provincial People’s Hospital, University of
Electronic Science and Technology of China, Chengdu, Sichuan, China
Full list of author information is available at the end of the article

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Wang et al. BMC Pregnancy and Childbirth (2021) 21:248 Page 2 of 14

Background There are various breastfeeding positions adopted by

Breastmilk provides all the energy and nutrients that the mothers. Traditional breastfeeding positions include the
infant needs for the first months of life, and it continues cradle, cross-cradle, side-lying and football positions,
to provide up to half or more of a child’s nutritional which are mostly dominated by the mother, ignoring the
needs during the second half of the first year and up to baby’s instincts and needs. Breastfeeding initiation is asso-
one third during the second year of life [1]. Two studies ciated with the release of inborn baby reflexes and in-
published in the journal Lancet [2, 3] showed that the stinctive mothering behaviours [19]. Biological Nurturing
lives of over 820,000 of children younger than 5 years of (BN), which was developed by Colson in the early 1990s
age could be saved every year if all children aged 0–23 [20] and is also known as laid-back breastfeeding (LBBF),
months were optimally breastfed. In 2012, the World refers to the placement of the mothers in a comfortable,
Health Assembly (WHA) Resolution 65.6 endorsed a semi-reclined positions where every part of the body is
comprehensive implementation plan on maternal, infant supported, especially the shoulders, neck and arms, while
and young child nutrition, which specified that by 2025, the baby lies prone or on the stomach and their bodies
the percentage of exclusive breastfeeding in the first 6 not flat but tilted up in the process of breastfeeding [21].
months should be increased to a target of up to at least BN is a breastfeeding concept that revolves around a re-
50% [4]. According to data from the World Health turn to biology and includes lactation concepts related to
Organization (WHO), only approximately 44% of infants the environment, reflex, intervention, and neurodevelop-
aged 0–6 months worldwide were exclusively breastfed ment. It is defined as a neurobehavioural approach to the
over the period of 2015–2020 [1]. initiation of breastfeeding to reduce latching problems
There are many factors that affect breastfeeding, and the accidental early cessation of breastfeeding [19].
among which the most important is the breastfeeding Biological nurturing can be used throughout the breast-
position. Inappropriate breastfeeding positions may have feeding period (from the time of birth to the end of breast-
a negative effect on the mother’s wellbeing and exacer- feeding). It is a collective term for mother-baby positions
bate related diseases through a negative impact on the and states that interrelate and interact to release primitive
infant’s positioning and latching and the duration of neonatal reflexes and spontaneous maternal breastfeeding
breastfeeding events [5]. According to a study [6], ap- behaviours [21].
proximately 70.3% of mothers suffered from breastfeed- However, at present, the varied quality of associated
ing difficulties, including cracked nipples, the perception studies on biological nurturing has led to controversial
of an insufficient amount of milk, pain, and fatigue. It is results. The laid-back position has not been popularized
estimated that 80–90% of mothers experience nipple in breastfeeding health education around the world, and
pain [7], and 58% of them experience nipple damage [8]. few high-quality studies have been performed to serve as
Nipple pain has been described by the mothers as sore a backbone for this approach with regard to the effects
nipples during and after breastfeeding [9], and it is the of breastfeeding. The goal of this paper was to evaluate
second most common reason for early weaning [10]. the effect of the laid-back position (biological nurturing)
Nipple trauma is a macroscopic traceable cutaneous le- on breastfeeding through evidence-based methods to
sion in the area of the nipple and areola that may occur provide references for the formulation and specification
in the form of fissures, eroded skin and ulcerations, or of breastfeeding position(s).
clinical evidence of erythema, oedema, blisters, white,
yellow, or dark stains, and ecchymosis [11]. The major Methods
causes of nipple pain and trauma are inappropriate The study was prepared according to the Preferred
breastfeeding techniques and improper infant position- Reporting Items for Systematic Review and Meta-
ing [10]. Nipple pain caused by an incorrect latching Analysis (PRISMA) guidelines [22] (see Additional file 1).
position is a common problem among breastfeeding All articles were imported into to a citation manager
mothers, which can lead to nipple trauma and pose an (EndNote X9), and duplicates were removed. Two
important obstacle to successful breastfeeding [12–14]. trained investigators (the first and second authors of this
Poor latching is associated with pain when breastfeeding. paper) searched the databases and screened the titles
In contrast, correct positioning and latching—in which and abstracts independently.
the infant’s gum line is placed well over the mother’s
lactiferous sinuses, the tongue is positioned under the Inclusion and exclusion criteria
areola, and both lips are flanged outward—are essential The criteria for studies to be included in this review
for increasing milk supply and intake [15–17]. Education were as follows: (1) participant groups included an ex-
regarding correct latching and infant positioning can perimental group, in which the mothers adopted a laid-
lead to a decrease in nipple pain and an increased dur- back breastfeeding (biological nurturing) position, and a
ation of breastfeeding [18]. control group, in which any traditional breastfeeding
Wang et al. BMC Pregnancy and Childbirth (2021) 21:248 Page 3 of 14

position, including the cradle, cross-cradle, side-lying Disagreements were resolved by discussion with all
and football positions, were used; (2) the effects of the members of the research team until a consensus was
intervention were assessed as the incidence of nipple reached.
pain, nipple trauma, correct latching position and pos-
ition comfort; and (3) a clinical study design, including Quality assessment
randomized controlled trials (RCTs) and quasi- The risk of bias (RoB) of each RCT was evaluated inde-
randomized controlled trials (Q-RCTs), was used. pendently by two investigators using the RoB 2.0 tool ob-
Studies were excluded if they (1) were not focused on tained from the Cochrane Handbook for Systematic
the effectiveness of the laid-back position on lactation- Reviews of Interventions (Version 62,019) [23], which in-
related nipple problems and comfort; (2) had no full text cluded the following domains: bias arising from the
available; (3) reported unextractable or unrelated raw randomization process, bias due to deviations from
data and the authors could not be contacted; (4) were intended interventions, bias due to missing outcome data,
published other than in English or Chinese; and (5) were bias in measurement of the outcome, and bias in selection
reviews, editorials, books, theses, news, etc. of the reported result. For each domain, the tool com-
prises a series of “signalling questions”, and once they
Search strategy were answered, the next step was to reach a risk-of-bias
We systematically searched the following twelve data- judgement and assign one of three levels to each domain
bases from inception to January 28,2020: Cochrane Li- [23, 24]: “low risk of bias”, “some concerns”, or “high risk
brary, EMBASE, Medline, Ovid, PubMed, Web of of bias”. Finally, risk-of-bias judgements within domains
Science, CINAHL, Scopus, Chinese National Knowledge were mapped to an overall judgement for the outcome.
Infrastructure (CNKI), China Biology Medicine disc The risk of bias of each quasi-randomized controlled trial
(CBM), WanFang and VIP. The search was carried out was evaluated independently by two investigators using
using the following keywords or medical subject head- the JBI Critical Appraisal Checklist for Quasi-
ings: [“breast-feed” OR “Feeding, Breast” OR “Breast- Experimental Studies (JBI, 2016) [25] by assigning “Yes”,
feeding” OR “Breast Feeding, Exclusive” OR “Exclusive “No”, “Unclear” or “Not applicable” for each of the 9
Breast Feeding” OR “Breastfeeding, Exclusive” OR “Ex- items. Any disagreements regarding the inclusion of stud-
clusive Breastfeeding” OR “Breast-feeding”] AND [“Laid- ies were resolved through discussion; if a consensus could
back” OR “Half lay” OR “Semi recumbent position” OR not be reached, a senior reviewer served as the final
“Semi-reclining position” OR “semirecumbent” OR “Half arbiter.
lying type” OR “semi supine position” OR “semiprone
position”] OR [“Biological Nurturing” OR “recommend- Statistical analysis
ing biological breeding” OR “Laid-back Breastfeeding” Statistical analyses were performed with Review Man-
OR “Laid-back breast feeding” OR “Half lay breast- ager Version 5.3 and STATA/SE Version 15.1 (Stata-
feeding”]. To obtain a full understanding of this topic, Corp, College Station, TX, USA). To eliminate man-
we also manually tracked the references in the included made errors and combine the functions of the different
articles and contacted investigators in the field to locate software programs, all the data were analysed separately
unpublished studies, but none were available. The search by two investigators using different programs (ZW:
strategies are listed in Additional file 2. STATA/SE and QL: RevMan). Dichotomous outcome
data were pooled using the risk ratio (RR) and presented
Data extraction and synthesis as the 95% confidence interval (CI), and continuous out-
Two reviewers independently assessed the studies for eli- come data are presented as the mean ± standard devi-
gibility and extracted the data using a standardized data ation (SD) and were pooled using the mean difference
extraction form, which was then checked by the third re- (MD) and 95% CI. For data for the same outcome pre-
viewer. Disagreements were resolved via discussion with sented in some studies as dichotomous data and in other
the third author. Studies selected for inclusion were studies as continuous data (for example, position com-
transferred to a Microsoft Excel spreadsheet for extrac- fort), we re-expressed the odds ratios as standard mean
tion of data items of: basic information from the in- differences (SMDs) according to the simple formula
cluded literature (first author, year of publication, study SMD = logor×(√3/π = 0.5513), computing them (or the
design), baseline characteristics (sample size, inclusion log odds ratios) and their standard errors for all studies
and exclusion criteria, delivery mode, maternal category, in the meta-analysis and allowing dichotomous and con-
gestational weeks, age mothers) and analysis indexes (in- tinuous data to be combined by using the generic
terventions, intervention time, outcomes). When infor- inverse-variance method [26, 27].
mation regarding the study methods and results was Heterogeneity was assessed statistically by using the
unclear, we contacted the authors for further details. Chi2 (χ2, or chi-squared) test and the I2 statistic. When
Wang et al. BMC Pregnancy and Childbirth (2021) 21:248 Page 4 of 14

p > 0.10 or I2 ≤ 50%, the results of the associated studies included studies were reported in English (one trial) and
were said to be homogenous or to have acceptable het- Chinese (eleven trials). No significant difference was ob-
erogeneity, and a fixed-effects model was utilized. When served between the two groups in terms of the studied
p ≤ 0.10 or I2 > 50%, it was considered that there was variables. All the included studies were published from
heterogeneity in the results of the multiple included 2017 to 2019. The intervention period of the included
studies, and subgroup analysis or sensitivity analysis was studies lasted from 3 days to 8 weeks. The age of the in-
performed to identify the sources of heterogeneity. fants was estimated to be 0–3 days according to the
Then, the selected studies were removed one by one, starting time of the intervention. The outcomes included
and the overall correlation results and I2 were recalcu- nipple trauma (n = 7), nipple pain (n = 8), correct latch-
lated. A random-effects model was selected if the hetero- ing position (n = 3) and position comfort (n = 4). We
geneity could not be eliminated. To assess the effects of established three subgroups based on intervention, deliv-
covariates on the pooled estimates, subgroup analysis ery mode and maternal category. Studies were divided
and meta-regression analysis were conducted [28, 29]. If into two groups according to whether they implemented
there was considerable variation in the results that could skin-to-skin care (SSC) [36]; in other words, whether the
not be removed, the meta-analysis was abandoned, and mother and baby had direct skin contact. In the sub-
the evidence was presented in a narrative form only. grouping based on intervention, the studies were divided
Publication bias was detected using Egger’s linear re- into the “LBBF” group and the “LBBF+SSC” group ac-
gression test [30] since no more than 10 original articles cording to whether the skin-to-skin care was performed
were enrolled in any analysis. p-values (two–tailed) < on the basis of laid-back breastfeeding. In the subgroup-
0.05 were considered statistically significant. For studies ing based on maternal delivery mode, the studies were
with publication bias, we conducted sensitivity analyses divided into the “vaginal delivery” group and the “vaginal
(trim and fill method) to explore the publication bias delivery & caesarean” group. In the subgrouping based
and the robustness of the meta-analysis conclusions to on maternal category, the studies were divided into the
different assumptions about the causes of the funnel plot “primipara” group and the “primipara & multipara”
asymmetry [31–35]. group according to whether the delivery times were re-
stricted. Further details about the included studies are
Results shown in Table 1.
Search results
The literature selection process is shown in the PRISMA Risk of bias assessment
flow diagram [22] (Fig. 1), including the reasons for exclu- The quality of all included RCT studies is shown in
sion. Initially, a total of 296 publications were retrieved Table 2 and Fig. 2. For the judgement of “bias arising
from the following 12 electronic databases: Cochrane Li- from the randomization process”, five [37–41] of the 11
brary (n = 7), EMBASE (n = 13), Medline (n = 14), Ovid included RCTs did not show detailed information on the
(n = 122), PubMed (n = 12), Web of Science (n = 31), random components in the sequence generation process,
CINAHL (n = 22), Scopus (n = 11), CNKI (n = 18), CBM eight studies [37–44] were judged to raise some con-
(n = 13), WanFang (n = 17) and VIP (n = 16). A search of cerns, and three studies [45–47] were judged to have a
the reference lists of the included studies yielded no add- low risk of bias. They concealed the allocation sequence
itional studies. After eliminating duplicates, 214 references with opaque envelopes that were sequentially numbered
were included. Then, the remaining 214 studies were and sealed with a tamper-proof seal. With regard to the
screened through their titles and abstracts, excluding an judgement of “bias due to deviations from intended in-
additional 179 articles. The remaining 35 articles were terventions”, only two studies [46, 47] reported compli-
screened through their full texts, of which 22 were ex- ance with the intervention, and they were judged to have
cluded because they were not appropriate study designs a low risk of bias. All included studies were judged to be
(n = 18) or interventions (n = 4). Moreover, one article was at low risk of bias in the judgement of “bias due to miss-
excluded because the data were difficult to extract, and we ing outcome data”. For the judgement of “bias in meas-
were unable to contact the author. Finally, 12 articles ful- urement of the outcome”, three studies [39, 41, 45] were
filled the eligibility criteria and were included in the meta- judged to raise some concerns, and the others [37, 38,
analysis. 40, 42–44, 46, 47] were judged to have a low risk of bias.
For the judgement of “bias in selection of the reported
Characteristics of the included studies result”, one study [45] was judged to have raised some
Twelve studies met the inclusion criteria, including concerns because the trial did not perform the analysis
eleven RCTs and one quasi-randomized controlled trial in accordance with a pre-specified plan, and ten studies
and consisting of 1936 participants (970 in the experi- [37–44, 46, 47] were judged to have a low risk of bias.
mental groups and 966 in the control groups). The Overall, three RCTs (27%) had a high RoB, six (55%)
Wang et al. BMC Pregnancy and Childbirth (2021) 21:248 Page 5 of 14

Fig. 1 PRISMA flow diagram of the literature search and study selection. *Twelve papers were included in meta-analysis. #Eleven studies were
included in RCTs, and one study was a Q-RCT

showed some concerns, and two (18%) had a low RoB source of the heterogeneity. After removing it, the result
for their outcomes. The quality of the one quasi- of the heterogeneity test with the remaining 7 studies
randomized controlled trial included is presented in decreased I2 to 73% (χ2 = 22.46, p = 0.001, I2 = 73%).
Table 3. Therefore, a random-effects model was utilized for the
meta-analysis, and the results showed that the experi-
Synthesis of results mental group had a lower incidence of nipple pain than
Nipple pain the control group (RR = 0.24; 95% CI 0.14, 0.40; p <
Eight studies [37–39, 41–44, 46], with a total of 1076 0.00001) (Fig. 3). It is worth mentioning that the result
pairs of postpartum women and their newborns, com- of the heterogeneity test decreased I2 to 0% (χ2 = 2.02,
pared traditional breastfeeding positions vs. laid-back p = 0.85, I2 = 0%) after removing the two studies [43, 46],
breastfeeding in terms of nipple pain. There was sub- probably because of the different measurement tools
stantial heterogeneity among these studies (χ2 = 125.27, used in the included studies.
p < 0.00001, I2 = 94%) according to the heterogeneity
test. It seems that one outlier [43] had a substantial in- Nipple trauma
fluence on the results of the overall meta-analysis ac- Seven studies [37–41, 45, 48], which included 1274 pairs
cording to sensitivity analyses and was thus a major of postpartum women and their newborns, reported
Wang et al. BMC Pregnancy and Childbirth (2021) 21:248 Page 6 of 14

Table 1 Characteristics of the studies included in the meta-analysis

Author Sample Study Vaginal Primipara/ Gestational Age of Intervention (E/ Age Intervention Outcomes
(year) size(n) design delivery/ Multipara weeks mother C) of period
(E/C) Caesarean (n) (Mean ± SD) (years) infant
(n) (E/C) (Mean ±
SD)
E C E C
(E/C)
Zhuang 75/75 RCT 38/ 35/ – – – 26.2 ± Laid-back 0 day 1-8w Nipple pain
(2019) [37] 37 40 4.7/ breastfeeding
25.3 ± (BN) /Traditional
4.5 breastfeeding
position
Shi et al. 84/84 RCT 50/ 52/ 56/ 55/ 36–39/ 27.98 ± Laid-back – 1-3d Nipple pain,
(2017) [38] 34 32 28 29 36–40 4.25/ breastfeeding Nipple trauma
28.51 ± (BN) /Traditional
4.69 breastfeeding
position
Li et al. (2017) 100/100 RCT 64/ 68/ 60/ 64/ 38–40/ 27.86 ± Laid-back <3d 1-3d Nipple pain,
[39] 36 32 40 36 37–40 4.25/ breastfeeding Nipple trauma,
27.43 ± (BN) /Traditional Position Comfort,
4.17 breastfeeding Correct latching
position position
Yu et al. 100/100 RCT 0/ 0/ 100/ 100/ 39.06 ± 1.08/ 27.43 ± Laid-back 0 day 1-3d Nipple trauma,
(2019) [40] 100 100 0 0 39.33 ± 1.06 4.14/ breastfeeding Position Comfort
27.40 ± (BN) /Cradle
3.81 breastfeeding
(Traditonal
position)
Zeng et al. 60/60 RCT 42/ 44/ – – 39.35 ± 1.23/ 26.75 ± Laid-back 0 day 1d-4w Nipple pain
(2019) [41] 18 16 39.42 ± 1.13 4.23/ breastfeeding
27.28 ± (BN) /Cradle
4.42 breastfeeding
(Traditonal
position)
Puapornpong 76/76 RCT 0/76 0/76 – – 38.5 ± 0.9/ 27.5 ± Laid-back 0 day 1d-6w Position Comfort
et al. (2017) 38.6 ± 1.0 5.9/ breastfeeding
[42] 27.1 ± (BN)
6.1 /Side-Lying
Breastfeeding
(Traditonal
position)
Liu et al. 49/49 RCT – – – – – – Laid-back – 1-4w Nipple pain,
(2019) [43] breastfeeding Nipple trauma
(BN)
/Traditional
breastfeeding
position
Zhang (2019) 74/70 RCT 58/ 56/ 74/0 70/0 38.89 ± 0.96/ 25.82 ± Laid-back 0 day 1d-6w Nipple pain,
[44] 16 14 39.09 ± 0.97 3.43/ breastfeeding Correct latching
26.16 ± (BN + SSC) position
3.62 /Cradle
breastfeeding
(Traditonal
position)
Zhao (2019) 48/48 RCT 48/0 48/0 – – 39.57 ± 1.06/ 26.31 ± Laid-back 0 day 1-3d Nipple pain
[45] 39.40 ± 1.11 2.82/ breastfeeding
27.27 ± (BN + SSC)
3.83 /Traditional
breastfeeding
position
Liang et al. 200/200 RCT 200/ 200/ – – – – Laid-back 0 day 1-3d Nipple trauma
(2017) [46] 0 0 breastfeeding
(BN + SSC)
/Traditional
breastfeeding
Wang et al. BMC Pregnancy and Childbirth (2021) 21:248 Page 7 of 14

Table 1 Characteristics of the studies included in the meta-analysis (Continued)

Author Sample Study Vaginal Primipara/ Gestational Age of Intervention (E/ Age Intervention Outcomes
(year) size(n) design delivery/ Multipara weeks mother C) of period
(E/C) Caesarean (n) (Mean ± SD) (years) infant
(n) (E/C) (Mean ±
SD)
E C E C
(E/C)
position
Wang (2019) 50/50 RCT 27/ 30/ 34/ 32/ – 27.9 ± Laid-back 0 day 0-1 m Nipple pain,
[47] 23 20 16 18 2.3/ breastfeeding Nipple trauma
27.7 ± (BN + SSC)
2.1 /Standard care
(Traditonal
position)
Lu et al. 54/54 Q-RCT – – 26/ 25/ 38.95 ± 0.45/ 26.88 ± Laid-back 0 day 0-1w Nipple trauma,
(2019) [48] 28 29 39.50 ± 0.50 3.32/ Breastfeeding Position Comfort,
26.76 ± (BN + SSC) Correct latching
3.25 /Standard care position
(Traditonal
position)
E experimental group, C control group, h hour, d day, w week, m month, SD standard deviation

nipple trauma. The results of the heterogeneity test for incidence of nipple trauma than the control group (RR =
these studies showed that there was substantial hetero- 0.47; 95% CI 0.29, 0.75; p = 0.002) (Fig. 4).
geneity (χ2 = 40.95, p < 0.00001; I2 = 85%), probably be-
cause of the different interventions used. However, the Correct latching position
sensitivity analyses did not show any study to substan- Three studies [38, 46, 48], which included 452 pairs of
tially influence the heterogeneity. Thus, a random-effects postpartum women and their newborns, reported on the
model was utilized for the meta-analysis, and the results correct latching position. The incidence of using the cor-
showed that the experimental group had a lower rect position for latching did not significantly differ

Table 2 Results of critical appraisal for Randomized Controlled Trials (Cochrane, 2019)
Study (year) Bias arising from the Bias due to deviations Bias due to Bias in Bias in selection of Overall
randomization from intended missing outcome measurement of the reported result risk-of-
process interventions data the outcome bias
Zhuang (2019) Some concerns Some concerns Low risk Low risk Low risk Some
[37] concerns
Shi et al. (2017) Some concerns Some concerns Low risk Some concerns Low risk High risk
[38]
Li et al. (2017) Some concerns Some concerns Low risk Low risk Low risk Some
[39] concerns
Yu et al. (2019) Some concerns Some concerns Low risk Low risk Low risk Some
[40] concerns
Zeng et al. Some concerns Some concerns Low risk Low risk Low risk Some
(2019) [41] concerns
Puapornpong Low risk Low risk Low risk Low risk Low risk Low risk
et al. (2017)
[42]
Liu et al. (2019) Some concerns Some concerns Low risk Low risk Low risk Some
[43] concerns
Zhang (2019) Low risk Low risk Low risk Low risk Low risk Low risk
[44]
Zhao (2019) Some concerns Some concerns Low risk Low risk Low risk Some
[45] concerns
Liang et al. Low risk Some concerns Low risk Some concerns Some concerns High risk
(2017) [46]
Wang (2019) Some concerns Some concerns Low risk Some concerns Low risk High risk
[47]
Wang et al. BMC Pregnancy and Childbirth (2021) 21:248 Page 8 of 14

Fig. 2 Risk of bias summary graph (RCT)

between the two groups (χ2 = 0.09, p = 0.95, I2 = 0%), so Position comfort
we used a fixed-effect model to pool the summary out- Four studies [38, 40, 47, 48] reported data on position
come. The results showed that the experimental group comfort, and these studies included 660 pairs of postpar-
had a higher incidence of using the correct position for tum women and their newborns. There were two dichot-
latching than the control group (RR = 1.22; 95% CI 1.11, omous data [38, 48] and two continuous data [40, 47]
1.33; p < 0.0001) (Fig. 5). among them. The results of the heterogeneity test
Wang et al. BMC Pregnancy and Childbirth (2021) 21:248 Page 9 of 14

Table 3 Results of critical appraisal for the quasi-experimental Subgroup analysis

studies (JBI, 2016) Three subgroup analyses were undertaken based on the
Questions (potential bias) Lu et al. intervention, delivery mode and maternal category. We
(2019) [48] evaluated the reliability of the outcomes, and the results
1. Is it clear in the study what is the ‘cause’ and what Yes are presented in Tables 4 and 5. For the outcome of nip-
is the ‘effect’? (causation/reverse causation)
ple trauma, the results of the subgroup analysis were, on
2. Were the participants included in any comparisons Yes the whole, the same as the overall results, and the direc-
similar? (selection bias)
tion did not change. There was no evidence of a differ-
3. Were the participants included in any comparisons Yes ent effect related to the intervention (p for interaction =
receiving similar treatment/care, other than the
intervention of interest? (history threat/systematic 0.24), delivery mode (p for interaction = 0.37), or mater-
difference/contamination bias) nal category (p for interaction = 0.37). The subgroup
4. Was there a control group? (measurement bias) Yes analysis for the different interventions showed that the
5. Were there multiple measurements of the outcome Yes experimental group had a lower incidence (RR = 0.68;
both before and after the intervention? (maturation 95% CI 0.47, 0.99) of nipple trauma than the control
threat, regression to the mean) group among subjects who performed LBBF, but the dif-
6. Was follow-up complete, and if not, was follow-up Yes ference was not significant (RR = 0.24; 95% CI 0.04, 1.31)
adequately reported and strategies to deal with loss to for the group that performed both skin-to-skin care and
follow-up employed? (attrition bias)
LBBF+SSC. The subgroup analysis for the different de-
7. Were the outcomes of participants included in any Yes
comparisons measured in the same way?
livery modes and maternal categories showed that the
(instrumentation/testing effects threats) vaginal delivery & caesarean (RR = 0.50, 95% CI 0.30,
8. Were outcomes measured in a reliable way? Yes 0.82) and primipara & multipara (RR = 0.50, 95% CI
(detection/instrument/measurement bias) 0.30, 0.82) groups both had a slightly higher incidence of
9. Was appropriate statistical analysis used? Yes nipple trauma than the caesarean (RR 0.32; 95% CI 0.13,
(performance / detection bias) 0.76) and primipara (RR = 0.32; 95% CI 0.13, 0.76)
groups, respectively. Similarly, the results of the sub-
group analyses for nipple pain indicate that there was no
evidence of a different effect related to the intervention
(p for interaction = 0.51), delivery mode (p for inter-
showed that there was substantial heterogeneity among action = 0.97), and maternal category (p for interaction =
these studies (χ2 = 25.58, p < 0.0001, I2 = 88%) using the 0.14). Overall, the results of the subgroup analysis
heterogeneity test, probably because of the different de- showed that all the experimental groups had a lower in-
livery modes included in the study. Nevertheless, the cidence of nipple trauma than the control groups, indi-
sensitivity analyses did not show any study to be sub- cating no change in the results of the study.
stantially influence the heterogeneity. Therefore, a
random-effects model was utilized for the meta-analysis,
and the results showed that there was no statistical sig- Publication bias
nificance between the two groups (ES = 0.09; 95% CI We used Egger’s linear regression test to detect the pub-
-0.63, 0.81; p = 0.798) (Fig. 6). lication bias arising from various influencing factors

Fig. 3 Forest plot for the incidence of nipple pain between the laid-back position and the traditional position in breastfeeding
Wang et al. BMC Pregnancy and Childbirth (2021) 21:248 Page 10 of 14

Fig. 4 Forest plot for the incidence of nipple trauma between the laid-back position and the traditional position in breastfeeding

quantitatively because concern remains that visual inter- Nipple pain is reported as one of the main causes of
pretation of the funnel plots is inherently subjective. The abandoning breastfeeding prematurely [49, 50]. Most
p-values for the correct latching position (p = 0.152) and women experience some degree of pain during breast-
position comfort (p = 0.138) were greater than 0.05, feeding, ranging from mild to severe, which may be ac-
which indicates that there is no significant publication companied by nipple trauma. Our meta-analysis showed
bias. Although the p-values for nipple pain (p = 0.008) that the experimental group had a lower incidence of
and nipple trauma (p = 0.013) were less than 0.05, there nipple pain than the control group (13.8% vs. 55.1%,
were no missing ‘counterparts’ to fill after the data were RR = 0.24; 95% CI 0.14, 0.40; p < 0.00001). This result is
analysed by the trim and fill method. This indicates that similar to a study carried out in Italy [51], which re-
the results of the two outcomes are stable and that the ported that biological nurturing significantly reduced the
effect of publication biases is negligible. In summary, the risk of sore nipples from 46.9 to 27.8% (RR 0.59, 95% CI
results showed no significant risk of publication bias 0.40, 0.88). These results may be explained by a higher
among the included studies. proportion of successful latching and self-attachment
with the laid-back position [51]. Nipple pain was mea-
sured on a rating scale that was developed based on the
Discussion characteristics of the general population. No unified and
This meta-analysis was conducted to estimate the effect specialized comprehensive assessment scale for nipple
of the laid-back position on lactation-related nipple pain has been formed.
problems. The results of this study showed that the ex- Nipple trauma is the main cause of nipple pain, and it
perimental group had a lower incidence of nipple is a well-recognized risk factor for breastfeeding cessa-
trauma (22.4% vs. 38.5%) and nipple pain (13.8% vs. tion [50]. Our results suggest that BN reduced the inci-
55.1%) than the control group. This suggests that the dence of nipple trauma by 16.1% (RR = 0.47; 95% CI
laid-back position has a positive effect on maternal 0.29, 0.75; p = 0.002). Nipple trauma includes nipple red-
breastfeeding with regard nipple pain, nipple trauma and ness and swelling, cracks, blisters, ulcers, keratinization
the correct position of latching. Further study regarding and defects [46]. Nipple cracks were the most common
position comfort remains to be conducted. type of nipple trauma in this study, and 4 studies [37,

Fig. 5 Forest plot for the correct latching position between the laid-back position and the traditional position in breastfeeding
Wang et al. BMC Pregnancy and Childbirth (2021) 21:248 Page 11 of 14

Fig. 6 Forest plot for the position comfort between the laid-back position and the traditional position in breastfeeding

40, 41, 45] showed that the laid-back position could help mother’s perception of an inadequate milk supply and
to reduce the incidence of nipple cracks compared with difficulty with latching [54]. This study indicated that
the traditional position (4.2% vs. 19.8%). Nipple trauma BN increased the success rate of “establishing the correct
causes pain and discomfort, which render it difficult for latching position” with an RR of 1.22 (95% CI 1.11, 1.33;
the mother to continue breastfeeding [52]. Nipple pain p < 0.00001). The laid-back position is conducive to
and nipple trauma exert an influence on each other. An obtaining the correct position of latching (89.5% in the
improper feeding position can interfere with the tissue intervention group and 73.7% in the control group),
repair process and can lead to further damage [12]. We which may contribute to successful breastfeeding. How-
should pay greater attention to the evaluation of these ever, this conclusion should be treated with caution be-
two aspects of breastfeeding. cause only three trials [38, 46, 48] were included.
Correction of positioning and latching is the most Position comfort in this study is regarded theoretically
common experience-based recommendation for the as a state of strengthening by having the needs of human
treatment of nipple pain [53]. A qualitative analysis to experience met, which causes mothers to be happy with
identify breastfeeding barriers in the early postpartum their health care in the process of breastfeeding [55]. It
period found that the most common barrier was the is unclear from this study whether the laid-back position

Table 4 Subgroup Analysis of the Effect of Intervention Elements on Nipple Trauma

Subgroups Number of Participants (n) Heterogeneity test Effects Meta-analysis Interaction
studies outcomes model p-value
(Experimental/Control) p-value I2 RR (95% CI)
(%)
Intervention 0.24
LBBF 4 [38–40, 43] 333/333 0.023 68.5% Random 0.68 (0.47, 0.99)
LBBF +SSC 3 [46–48] 304/304 0.000 90.2% Random 0.24 (0.04, 1.31)
Deliver mode 0.37
Caesarean 1 [40] 100/100 – – Random 0.32 (0.13, 0.76)
Vaginal delivery & caesarean 6 [38, 39, 43, 46–48] 537/537 0.000 85.8% Random 0.50 (0.30, 0.82)
Maternal category 0.37
Primipara 1 [40] 100/100 – – Random 0.32 (0.13, 0.76)
Primipara & multipara 6 [38, 39, 43, 46–48] 537/537 0.000 85.8% Random 0.50 (0.30, 0.82)
Wang et al. BMC Pregnancy and Childbirth (2021) 21:248 Page 12 of 14

Table 5 Subgroup Analysis of the Effect of Intervention Elements on Nipple Pain

Subgroups Number of studies Participants (n) Heterogeneity test Effects Meta-analysis Interaction
outcomes model p-value
(Experimental/Control) p-value I2 RR (95% CI)
(%)
Intervention 0.51
LBBF 5 [37–39, 41, 43] 368/368 0.000 96.9% Random 0.23 (0.06, 0.94)
LBBF +SSC 3 [44, 45, 47] 172/168 0.096 57.3% Random 0.39 (0.21, 0.71)
Deliver mode 0.97
Vaginal delivery 1 [45] 48/48 – – Random 0.27 (0.15, 0.51)
Vaginal delivery & caesarean 7 [37–39, 41, 43, 44, 47] 492/488 0.000 94.9% Random 0.28 (0.12, 0.66)
Maternal category 0.14
Primipara 1 [44] 74/70 – – Random 0.57 (0.39, 0.84)
Primipara & multipara 7 [37–39, 41, 43, 45, 47] 466/466 0.000 95.6% Random 0.24 (0.08, 0.70)

is superior to the traditional position regarding comfort the whole process. Thus, we should focus on this issue
in the period of breastfeeding, because the available in future studies and take measures to ensure compli-
current evidence did not reveal a significant difference ance, such as videotaping with informed consent.
in position comfort between the two groups. This could All the data were analysed separately by two investiga-
be due to the small sample size of the included studies tors using different software programs. The results show
or the different types of data, which weakens the assess- that this method can effectively avoid human errors such
ment of the results of the meta-analysis. Thus, additional as data entry errors and improper operation, and it also
research about the effect of the laid-back position on combines the functions of the different programs. We
position comfort should be conducted in the future. found that, in practice, the I2 and Z values of the con-
Breastfeeding is a biology-based nurturing method tinuous variables obtained by the two software programs
rooted in human instinct [21]. Laid-back breastfeeding were slightly different, but this did not affect the out-
can be adopted even if there is early separation after birth comes, which is probably related to the algorithms used
or the mother is suffering from problems with breastfeed- by the software; all other results from the programs were
ing. The National Childbirth Trust (NCT) breastfeeding identical.
counsellor Ros Vinall [56] considers that biological nurt-
uring or “laid-back breastfeeding” taps into the mothers’ Limitation
and babies’ own instincts to successfully perform breast- The present meta-analysis has some potential limita-
feeding. She also highlighted that BN approach can re- tions: (1) We considered all RCTs and quasi-randomized
move breastfeeding from the medical model, with its need controlled trials published in English and Chinese; stud-
for instruction and prescriptive rules. Colson’s research ies published in other language were not included, lead-
emphasizes the biological underpinnings of breastfeeding, ing to potential selection bias; (2) The heterogeneity for
empowering parents to be active participants in feeding certain comparations was significant, which may have
rather than merely relying on the instincts of the infant influenced the pooled results, despite our using a
[21]. Laid-back breastfeeding is a revelation for human be- random-effects model; (3) Three subgroups analyses
ings, as it accords with our humanist, non-interventionist were performed according to intervention, delivery mode
and back-to-biological spirit. and maternal category, but other factors that could in-
The quality of the included studies was moderate, and fluence the outcomes might be present; and (4) In this
the results should be interpreted with caution. Many of study, only quantitative indicators were analysed, and
the original studies implemented a single-blind design. the vast majority of the included studies were published
The nurses who followed up with the breastfeeding out- in Chinese, because most of the studies obtained from
comes did not know the breastfeeding position groups, the search were qualitative reports written in other
and none of the included studies reported whether the countries.
researchers who analysed data knew which was the ex-
perimental group. Few of the original studies reported Conclusions
compliance with the intervention. The reason might be The results of this meta-analysis suggest that the laid-
that breastfeeding is a private activity, and researchers back position is helpful for solving lactation-related nip-
can only provide guidance, making it difficult to monitor ple problems and can be used as a recommended
Wang et al. BMC Pregnancy and Childbirth (2021) 21:248 Page 13 of 14

position for breastfeeding. Nurses and researchers may Author details

1
instruct mothers to assume the laid-back position to de- School of Medicine, University of Electronic Science and Technology of
China, Chengdu, Sichuan, China. 2School of Nursing, North Sichuan Medical
crease the incidence of nipple pain and nipple trauma College, Nanchong, Sichuan, China. 3Department of Nursing, Sichuan
during breastfeeding. However, no significant difference Provincial People’s Hospital, University of Electronic Science and Technology
in position comfort was found between the two groups of China, Chengdu, Sichuan, China.

based on the current evidence. Further high-quality and Received: 6 July 2020 Accepted: 15 March 2021
large-scale studies are needed to validate these results
due to the limitations of the included studies.

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