A study of prenatal nutrition among low-income Latinas in Hartford shows that food insecurity, and maternal weight gain during pregnancy that is lower than recommended by the national Institute of Medicine, are both independently linked with low birth weight.
“Food insecurity – the inability to access nutritional food in sufficient quantities – and insufficient weight gain during pregnancy predict a low birth weight baby,” says Rafael Pérez-Escamilla, professor of nutritional sciences and director of UConn’s Center for Eliminating Health Disparities among Latinos (CEHDL), which conducted the study.
Low birth weight is, in turn, a predictor of a child’s long-term health.
The study also found that there are major differences in quality of diet between Latinas who have recently arrived in this country and those who have been here longer.
Working in collaboration with the Hispanic Health Council, Hartford and St. Francis hospitals, and other community agencies, the researchers recruited pregnant Latina women mostly during their second trimester.
On two occasions during the pregnancy and once after the infant’s birth, bilingual/bicultural interviewers collected data including the participants’ dietary intake, food security status before and during pregnancy, meal-skipping patterns, pre-pregnancy body mass index, gestational weight gain, and infant birth weight.
Only 25 percent of the study participants gained the recommended amount of weight during pregnancy.
Approximately 30 percent gained less than the recommended amount, while 45 percent gained more than is recommended.
Women were at increased risk of gaining excessive weight during pregnancy if they experienced household food insecurity.
The highest rates of excessive gestational weight gain were seen among those women who were overweight or obese before pregnancy.
Forty-three percent of the women in the study were overweight or obese before pregnancy, with more than 80 percent of overweight women and 50 percent of obese women gaining more weight than recommended during pregnancy.
“Being overweight is an extremely serious problem during pregnancy,” says Pérez-Escamilla, who is currently serving on an Institute of Medicine committee to revise the national guidelines on weight gain during pregnancy.
“It can lead to gestational diabetes and to either low birth weight or macrosomic – very large – babies. Individuals born with either low or high birth weight are more likely to develop diabetes and other diseases later in life.”
A mother’s excessive gestational weight gain can also adversely affect an infant’s weight at birth and subsequent growth.
Even though these associations were not examined in this study, Pérez-Escamilla says other studies have shown that gaining an excessive amount of weight during pregnancy causes hypertension (high blood pressure), which limits the blood supply to the fetus.
With inadequate nutrition, the fetus becomes ‘programmed’ to live in an environment where there is not enough food. Yet a baby born in the U.S. is born into an environment where an enormous amount of calories are available.
“If a child has a low weight at birth and gains weight rapidly during the first couple of years, that’s a pretty lethal combination for the future,” he says.
“These populations are at high risk of developing various chronic diseases as a result of this early programming.”
But steps to reduce weight need to be taken before, not after, a woman becomes pregnant, he notes.
| Professor Rafael Pérez-Escamilla, right, discusses a nutrition guide with Angela Bermúdez-Millán, left, and Amber Hromi-Fiedler, who conducted a study of prenatal nutrition among Latinas in Hartford.
|Photo by Frank Dahlmeyer
“It may be too late to start doing something about a woman’s weight when she’s already pregnant, because of the risk to the fetus. It’s really important to enter pregnancy with a healthy weight.”
The study also found that Latinas who have recently arrived in this country have a significantly better diet than those who have been here longer.
The recent immigrants in the study came mostly from Mexico and Central and South American countries, whereas those who were more established were mostly of Puerto Rican descent.
The researchers found that the non-Puerto Rican Latinas prepared more meals from scratch, including fresh vegetables, and ate fast food less often, despite being extremely poor and generally having no access to programs such as food stamps.
“Those who have moved here recently bring with them a lot of dietary habits from their home countries,” says Pérez-Escamilla.
“The Puerto Rican women, who have lived here on average about 15 years, have been more exposed to U.S. dietary patterns.”
The non-Puerto Rican women also had a more extensive social support network than the Puerto Ricans.
He predicts, however, that without efforts to preserve them, these positive characteristics will be eroded by exposure to U.S. culture.
From research to advocacy
Pérez-Escamilla hopes to use the findings to advocate for more federal and state funding for pre- and peri-conceptional and infant nutrition.
“Pre-conceptional nutrition affects two generations – it’s about the well being of both mom and baby,” he says. “It’s crucial for the future workforce.”
About two-thirds of the pregnancies in the study were not planned, so pre-conception nutrition education must target all women, regardless of whether they intend to become pregnant, says Amber Hromi-Fiedler, one of the principal investigators on the study and now assistant director of the research core for CEHDL.
“If you educate a woman before she gets pregnant about good nutritional habits and how to access nutritious foods, then if she does get pregnant unintentionally, there will be less chance of a poor pregnancy outcome,” says Hromi-Fiedler.
Angela Bermúdez-Millán, also a principal investigator on the project, now the coordinator of the community core for CEHDL and a postdoc with Pérez-Escamilla, says efforts to improve the nutritional status of Latinas must involve collaboration among community agencies, hospitals, schools, and the WIC program.
In addition, she says, to be effective, an intervention must take into account many factors, including the women’s length of stay in the U.S., social support, number of children, participation in programs such as food stamps and WIC, and access to a grocery store.
“There are many factors that can influence prenatal nutrition and birth outcomes,” says Bermúdez-Millán.
CEHDL has developed a prenatal nutrition guide in Spanish and English, featuring photos of Latina women, as well as foods popular among the Latino community, such as plantains.
The study was funded by CEHDL, a National Institutes of Health, National Center on Minority Health and Health Disparities-funded center, and the University of Connecticut Research Foundation.
The Center, established in 2005, recently received the 2007 C. Peter Magrath/W.K. Kellogg Engagement Award for the northeast region.