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Farm Work & Preterm Low Birthweight Among Hispanic Women

Study of Hispanic Acculturation Reproduction and the Environment (SHARE)

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT00015613
Enrollment
1500
Registered
2001-04-25
Start date
1998-08-31
Completion date
2001-09-30
Last updated
2005-11-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Infant, Low Birth Weight, Infant, Premature, Diseases

Keywords

Hispanics, Acculturation, Maternal Exposure, Infant, Low Birth Weight, Infant, Premature, Organophosphates, Pesticides, Stress, Nutrition

Brief 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.

Interventions

None listed

Sponsors

National Institute of Environmental Health Sciences (NIEHS)
Lead SponsorNIH

Study design

Observational model
DEFINED_POPULATION
Time perspective
OTHER

Eligibility

Sex/Gender
FEMALE
Age
12 Years to 40 Years
Healthy volunteers
Yes

Inclusion criteria

Pregnant Hispanic women receiving prenatal care services at San Joaquin General Hospital's Healthy Beginnings Clinics in Stockton California

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026