Table 1 Description of included studies

Hao et al., (2022)

China

Cross sectional

Mothers aged 20–42 with children under the age of 2 (N = 1677)

Breastfeeding outcome: Exclusive breastfeeding 0–6 months

Logistic regression

Women in informal employment had lower odds of practicing exclusive breastfeeding compared to mothers in formal employment (OR = 0.45, 95% CI = 0.28–0.72, p = 0.004)

Moderate

Sanches et al., (2011)

Brazil

Cross sectional

Mother/infant pairs of infants with low birth weight (N = 170)

Breastfeeding outcome: Interruption of exclusive breastfeeding up to three months

Hierarchical poisson multiple regression

Informal employment was found to be a protective factor to interruption of exclusive breastfeeding (PR = 0.70, 95% CI = 0.55–0.89, p = 0.003)

High

Nkrumah (2016)

Ghana

Cross sectional

Mother/infant pairs (children aged 0–7 months)

(N = 225)

Breastfeeding outcomes: Exclusive breastfeeding (0–6 months) and breastfeeding frequency (≥ 8 times/day or < 8 times/day)

Chi square

84% of women in informal employment exclusively breastfed compared to 16% of women in formal employment. 91% of women in informal employment breastfed more frequently, while 9% of women in formal employment breastfed more frequently. The associations between mothers in formal and informal employment and breastfeeding outcomes were significant (p = 0.020 for exclusive breastfeeding and p = 0.021 for breastfeeding frequency)

Moderate

Chen et al., (2019)

China

Cross-sectional

Mothers with children under 12 months (N = 3878)

Breastfeeding outcomes: Early initiation of breastfeeding (EIB), exclusive breastfeeding under six months (EBF), predominant breastfeeding under six months (PBF), children ever breastfed (ever BF), current breastfeeding (CBF)

Logistic regression

Both migrants (AOR = 0.69 CI = 0.51–0.92) and locals (AOR = 0.71, CI = 0.54–0.94) that were informally employed had significantly lower odds to CBF compared to those who were formally employed. Informally employed migrants also had significantly lower odds to EIB as compared to formally employed migrants (AOR = 0.59, CI = 0.38–0.90). There was no difference in EIB between local informally employed or local formally employed women (AOR = 0.93, CI = 0.62–1.39). There was no difference between employment types and any other breastfeeding practices (Ever BF, EBF or PBF)

High

Child nutritional status and low birthweight

Jafree et al., (2015)

Pakistan

Cross sectional

Employed women in paid work with at least one child born in the last 5 years (N = 2515)

Low birthweight

Multivariate binary logistic regression

Children of mothers in informal employment had lower odds of having low birth weight, the results were not significant (AOR = 0.72, 95% CI = 0.47–1.09, p = 0.126)

High

Engle (1991)

Guatemala

Cross sectional

Mother/child pairs (children aged 8–35 months old) (N = 239)

Nutrtional status (anthropometric measurements): Height-for-age z score (HAZ), weight-for-age z score (WAZ) and weight-for-height z scores

ANCOVA

HAZ: the mean was − 1.79 for children of mothers in informal work and − 1.66 for children of mothers in formal work

WAZ: the mean was − 1.39 for children of mothers in informal work and − 1.08 for children of mothers in formal work

Weight for height: the mean was − 0.34 for children of mothers in informal work and − 0.05 for children of mothers in formal work

In the initial ANOVA, there was a significant relationship between the mother’s type of work with height for age and weight for age, the relationship was no longer significant after adjusting for confounders. There was no association between mothers’ type of work and weight for height

High

Toyama (2001)

Indonesia

Cross sectional

Children under the age of 5 (N = 64)

Nutrtional status: Height-for-age z score (HAZ) and weight-for-age z score (WAZ)

Mulitple linear regression

Children of mothers in informal work were significantly more likely to have poor nutritional status compared to children of mothers in formal work. The mean HAZ for children of informally employed mothers was − 1.56 and mean HAZ was − 0.14 for children of formally employed mothers was (p = < 0.01). Mean WAZ for children of informal mothers was − 1.75 compared to a mean of -0.67 among children of formally employed mothers (p = < 0.01)

Moderate

Nakahara et al., (2006)

Nepal

Cross sectional

Mother/child pairs (children aged 10–24 months) (N = 72)

Nutritional status (anthropometric measurements): Underweight (weight-for-age z score ≤ -2) and stunting (height-for-age z score ≤ -2)

Logistic regression

Underweight: Children of mothers in informal employment had higher odds of being underweight compared to children of mothers in formal employment (AOR = 31.07; 95% CI = 1.46–663; p = 0.03).

Stunting: Children of mothers in informal employment had higher odds of reporting stunting compared to children of mothers in formal employment but these results were non-significant (AOR = 1.61; 95% CI = 0.17–15.5; p = 0.68)

High

Antenatal care

Ha et al., (2015)

Vietnam

Cross sectional

Mothers who gave birth in the last year, living in rural areas of Vietnam (N = 907)

Utilization of more than four antenatal care services (ANC4+) services

Multivariate logistic regression

Mothers with a formal job, i.e., business owners (OR = 3.1, 95% CI = 1.08–8.78) and government officials (OR = 1.9, 95% CI = 1.11–3.26), had higher odds of using ANC4 + services than mothers with informal jobs

High

Ihomba et al., (2020)

Kenya

Cross sectional

Women admitted to a local referral hospital in Kenya with pregnancy or childbirth related complications (N = 353)

Birth preparedness and complication readiness (BPCR)

Chi square

Formal employment was associated with women having higher odds of reporting BPCR (OR = 4.14, 95% CI = 2.51–6.82, p < 0.001) compared to women in informal employment

High

Agbozo et al., (2022)

Ghana

Cross sectional

Pregnant women attending antenatal clinics (N = 817)

Adherence to appointments for Gestational Diabetes Mellitus (GDM) testing

Logistic regression

Women in formal employment had higher odds of adhering to their scheduled GDM test compared to informal workers, the result was not significant (AOR = 1.46, 95% CI = 0.56–3.77, p = 0.430)

High

General health outcomes

Santana and Loomis (2004)

Brazil

Cross sectional

Paid workers aged 18–65, stratified by age and sex (N = 1370)

Non-fatal occupational injuries

Poisson regression

There was no significant association between informal employment and non-fatal occupational injuries for any of the age groups. Workers in informal employment aged 18–21 had the highest incidence rates of occupational injuries (IRR 1.72, 95% CI = 0.33–8.83), followed by women aged 22–40 (IRR, 1.69, 95% CI = 0.90–3.16)

Moderate

Sousa et al. (2010)

Spain

Cross sectional

Foreign-born and Spanish-born workers, stratified by sex and residence status (N = 2358)

Self-rated health and mental health

Logistic regression

Poor self-rated health:

Compared with Spanish-born formal workers

Foreign-born informal workers living in Spain > 3 years had higher odds of reporting poor self-rated health (AOR = 4.63, 95% CI = 1.95–10.97)

Foreign-born informal workers who had lived in Spain ≤ 3 had lower odds of reporting poor self-rated health (AOR = 0.53, 95% CI = 0.62–4.59), and Spanish-born informal workers had higher odds of reporting poor mental health (AOR = 1.32, 95% CI = 0.41–4.27). Neither of these association were significant

Poor mental health:

Compared with Spanish-born formal workers

In the univariate model, foreign-born informal workers living in Spain > 3 years had significantly higher odds of reporting poor mental health (OR = 2.41, 95% CI = 1.22–4.75). After testing for confounders, the results were no longer significant (AOR = 1.93, 95% CI = 0.95–392)

Spanish-born informal workers (AOR = 1.11, 95% CI = 0.50–3.48) had higher odds of reporting poor mental health. Foreign-born informal workers living in Spain ≤ 3 had lower odds of reporting poor mental health (AOR = 0.71, 95% CI = 0.20–2.50). Neither of these associations were significant

High