Sociodemographic characteristics of mother’s population and risk of preterm birth in Chile

Abstract

BackgroundPreterm birth is a global problem in Perinatal and infant Health. Currently is gaining a growing attention. Rates of preterm birth have increased in most countries, producing a dramatic impact on public health. Factors of diverse nature have been associated to these trends.In Chile, preterm birth has increased since 90. Simultaneously, the advanced demographic transition has modified the characteristics of woman population related to maternity.The principal objective of this study is to analyze some sociodemographic characteristics of the maternal population over time, and their possible association to rates of preterm birth. The second aim is to identify groups of mothers at high risk of having a preterm child.MethodsThis population-based study examined all liveborn singletons in Chile from 1991 to 2008; divided in three periods. Preterm birth rates were measured as % births <37 weeks of gestation.Logistic regression assessed the risk of preterm birth associated with mother’s age, parity, and marital status, expressed as crude and adjusted odds ratios.ResultsOver time, rates of preterm birth increased in overall population, especially during the third period (2001–2008). In the same time, characteristics of maternal population changed: significant increase of extreme reproductive ages, significant decrease in parity and increase in mothers living without a partner.Risk of preterm birth remained higher in groups of mothers: <18 and >38 years of age; without a partner; primiparas and grandmultiparas. However, global increase in preterm birth was not explained by the modification of socio demographics characteristics of maternal population.ConclusionsSome socio demographic characteristics remained associated with preterm birth over time. These associations allowed identifying five groups of mothers at higher risk to have a preterm child in the population.Increase in overall preterm birth affected all women, even those considered at “low sociodemographic risk” and the contribution of more recent period (2001–2008) to this increase is greater.Then, studied factors couldn’t explain the increase in preterm birth. Further research will have to consider other factors affecting maternal population that could explain the observed trend of preterm birth.

The Relationships of Health Behaviour and Psychological Characteristics with Spontaneous Preterm Birth in Nulliparous Women

“…Possible confounders, based on earlier research, were partner status (Lopez and Breart 2013), high (>35 years) and low (<20 years) maternal age (Ip et al 2010), low maternal education and being of ethnic minority (Goldenberg et al 2008). Potential anthropometric confounders are maternal underweight and overweight (Torloni et al 2009) and lower maternal height (different studies use various categories and cut-off points ranging from <150 to 170 cm) (Han et al 2012).…”

Risk factors associated with preterm birth after a prior term delivery

“…These acquired risk factors are primarily those associated with lifestyle and behaviour and may include marital status, insurance status, and substance abuse. [3][4][5][6][7][8][9][10][11][12][13][14] A detrimental change in these factors between pregnancies may place seemingly low risk women at increased risk for PTB.…”

Prediction of the Effect of Demographic Characteristics on Parity Using Poisson Regression Model

“…Many of demographical studies use descriptive statistics to explain the relationship among factors studied [11,12,13]. Such studies are limited in their power to make inferences on effect of demographic characteristics on the variable of interest.…”