This section presents a detailed review of the literature.

In his study, Harpham (2008) examined how the economic, social, environmental, and health service factors impact the health of urban poor people. Low socioeconomic status contributes to a variety of health-related issues. According to Almeida LM and Caldas JP's (2013) research, migrating women have varying perspectives on possible barriers to obtaining healthcare services, most of which are based on personal experiences. In their study, Kumar et al. (2009) focused on how little maternity care services are really used. About 50% of pregnant women in the lowest quintile do not obtain IFA pills, and 75% do not receive additional nutrition through Anganwadi. Several relevant difficulties were raised, such as the lack of knowledge regarding the supplemental nourishment provided by Anganwadi centers. The lack of knowledge regarding the supplemental nutrition provided by Anganwadi centers despite its accessibility is one of the connected difficulties that came up. Reddy (2014) noted the significance of maternal health in the context of India. Maternal mortality is high in India, and one-third of women have some form of reproductive health issue. Due to bigger families, more frequent births, poverty, and illiteracy, this issue is considerably more concerning for slum women. According to M.Thamilarasan (2016), maternal deaths make about 15% of all deaths among women who are fertile. Sepsis, anemia, and hemorrhage are the main causes of maternal fatalities. Prenatal and postpartum care is typically unavailable to older women, women from isolated tribes, uneducated women, and women with modest incomes.

 Different organizations define “slum” in different ways. A slum is defined as an urban area characterized by unplanned growth, poor buildings, poor sanitation and high population density. Although their characteristics vary from geographical region to region, they are usually inhabited by very poor or socially disadvantaged people. Most slums lack clean water, electricity, sanitation and other basic services. According to the UN organization UN-HABITAT, a slum is an area that combines the following characteristics to varying degrees: insufficient access to clean water; inadequate access to sanitation and other infrastructure; poor construction quality of the apartment; overcrowding; and uncertain residential status. Slums are typically characterized by urban decay, high levels of poverty, illiteracy and unemployment. According to Section 3 of the Slum Improvement and Elimination Act of 1956, slums are primarily residential areas where apartments are not suitable for human habitation due to decay, overcrowding, improper layout and design of buildings and narrowness. Or improper street design, lack of ventilation, lighting, sanitation or a combination of these factors detrimental to safety, health and morals.

 Khan et al. (2008) slums are spatial manifestations of urban poverty, social exclusion and inappropriate government policies and are often characterized by one or more of these disadvantages: dilapidated or poorly built houses that are overcrowded, precarious management, poor environmental management such as inadequate access.  For clean drinking water and sanitation, stagnant water and poor drainage with open sewers, excessive amounts of uncollected garbage, overcrowding, flies and poor lighting.  According to R.E Dickinson, “Slum indicates an exceedingly light-filled space where the dwelling is so unfit to be an instrument of the health and morals of the community.

 Urbanization, industrialization, higher productivity of the secondary/tertiary sector compared to the primary sector make cities centers of economic growth and jobs. Cities act as beacons for rural people because they represent a higher standard of living and offer people opportunities that are not available in rural areas. This leads to large-scale migration from rural areas to cities. The negative consequences of urban attractiveness lead to slums characterized by a lack of housing and a critical lack of public services, overcrowding, unhealthy conditions, etc.

Table 1. Percent Urbanization & Slum Concentration, in Indian states/territories, 2001

Source: Census of India, 2001

Between 2001 and 2011, urbanization increased more quickly. According to the census, between 2001 and 2011, there were 377 million people living in urban areas, representing a 2.76 percent annual growth rate. Overall, the country's urbanization grew from 27.7% in 2001 to 31.1% in 2011—a rise of 3.3 percentage points from 2001 to 2011 compared to a rise of 2.1 percentage points from 1991 to 2001. Urban population growth includes the natural rise, net rural-urban categorization, and rural-to-urban migration. The pattern of urbanization at the state level varies greatly, although economically developed states often exhibit greater rates of urbanization. ( Bhagat,2011).

Reproductive-related deaths and illnesses are highest among poor women worldwide, and especially among women in developing countries. About a third of the total burden of disease  among women aged 15-44 in  developing countries is related to health problems caused by pregnancy, childbirth, abortion and genital infections (World Bank, 1993). Reproductive health is described by several indicators such as total birth rate, contraceptives, antenatal care and delivery practices, etc. Unsanitary, unhygienic and cramped living conditions in slums negatively affect the health of residents in general and the reproductive health of women in particular (Khanam 2016). Maternal deaths would result due to inadequate prenatal, delivery and postnatal care services, which would represent disparities in the accessibility and availabilities of these health care services. despite having many maternal health program India still high maternal mortality. Antenatal care services, delivery, and postnatal care (PNC) services are all related to maternal health care services, which includes the wellbeing of women during pregnancy, childbirth, and after delivery.

Socioeconomic and demographic variables are highly significant and consistent predictors of health-related behaviors among Indian women (Mahpatro, 2012). Variables measuring the socio-economic status of the respondent include female education (illiterate, primary, secondary and higher education), male education (illiterate, primary, secondary and higher education), women’s current employment status (not working and working), husband’s employment. Status (not working and working), Economic status of household (poorest, poorest, middle, richest, richest), caste (SC, ST, OBC etc.), age of women, order of birth, place of residence (city vs. rural). Several literatures have emphasized the health status of migrant women. The health status of migrant women depends on socio-economic conditions such as place of residence, religious standard of living, and economic status of the household and caste system.