Farm Work & Preterm Low Birthweight Among Hispanic Women
Condition: Infant, Low Birth Weight; Infant, Premature, Diseases
MeSH terms: Infant, Premature, Diseases; Birth Weight
Study type: Observational

Summary: 
      The most persistent and intractable cause of infant and child mortality and morbidity in the
      US remains preterm and low birthweight deliveries. Pregnant women in the United States
      experience the highest incidence of these complications among developed countries. Even more
      disturbing is the observation that immigrant Hispanic women experience worsening birth
      outcomes the longer they live here, despite increasing access to prenatal care, improved
      socio-economic status and better education. The purpose of this study is to identify the
      potential acculturation-related risk factors for preterm and low birthweight (PTLBW) delivery
      among Hispanic women of varying lengths of US residency. It is hypothesized that changes in
      factors associated with acculturation, such as poor nutritional intake, job stress and
      occupational exposures to pesticides or other hazards, and certain types of genital
      infections, can best explain the worsening of pregnancy outcomes among Hispanic immigrant
      women.
    

Detailed description: 
      The most persistent and intractable cause of infant and child mortality and morbidity in the
      US remains preterm and low birthweight deliveries. Pregnant women in the US experience the
      highest incidence of these complications among developed countries. Despite many efforts at
      increasing prenatal care, rates of preterm delivery have not substantially changed in the
      last decade. Even more disturbing is the observation that immigrant Hispanic women experience
      worsening birth outcomes the longer they live in the US, despite increasing access to
      prenatal care, improved socio-economic status and better education. (Within five years after
      moving to the US, the odds ratio for preterm low birth weight delivery increases by 1.9, from
      4% to 7%.)

      As migrant women become acculturated to the US, they must be exposed to factors that
      adversely affect pregnancy outcomes. But the known risk factors, such as poverty, lack of
      education, smoking, substance abuse, inadequate pregnancy weight gain, low pre-pregnancy
      weight, high altitude, chronic diseases, primipara, and high parity, explain only a small
      percentage of this change in incidence.

      The prospective study will enroll a cohort of approximately 1500 pregnant Hispanic women
      attending prenatal care services through an OB/GYN group at the San Joaquin General Hospital
      in Stockton, CA. The majority of Hispanic women (67%) receiving prenatal care through this
      group are Mexican immigrants of varying lengths of US residency, and up to 26% of them are
      involved in farm labor and/or other types of manual labor. Eighteen percent are US-born
      Mexican women. A study of this unique population of Hispanic women of varying lengths of US
      residency, and factors related to occupational risks, acculturation and preterm low birth
      weight deliveries, will provide an excellent opportunity to examine the factors of
      acculturation-based causes of preterm low birthweight (PTLBW).

      The investigators hypothesize that job stress and occupational exposures related to farm work
      can best explain the worsening of pregnancy outcomes among Hispanic women. However, in order
      to ensure an understanding of the mechanism of this increased rate of preterm low birthweight
      within this population, this study will also examine other risk factors that could possibly
      be associated with acculturation and preterm low birthweight. Such factors include changes in
      nutrition intake, and certain types of genital infections such as Bacterial Vaginosis,
      Gonorrhea and Chlamydia.

      The knowledge that emerges will have direct application for designing improved programs for
      the prevention of preterm low birthweight deliveries among Hispanic women. Just as important,
      it will provide insight into the underlying causes of the scandalously high rates throughout
      all US populations.
    

Observational model: Defined Population
Time perspective: Other
Keywords: Hispanics; Acculturation; Maternal Exposure; Infant, Low Birth Weight; Infant, Premature; Organophosphates; Pesticides; Stress; Nutrition