Babies born to teens are more likely to be born prematurely and have a low birth weight, according to the Mayo Clinic. Not receiving proper prenatal care contributes to the complications that can arise in teen pregnancies.

An international reach

The interplay between teenage births, poverty and infant mortality isn't unique to the United States.

Catalina Escobar, one of the top 10 CNN Heroes of 2012, knows all too well how much young mothers need medical support and education to give birth to healthy children. In Escobar's country, Colombia, the infant mortality rate is 15.92, much higher than any state in the U.S.

Colombia's colorful city of Cartagena is an attractive tourist destination, with its historical grandeur and beach resorts. Acclaimed author Gabriel Garcia Marquez set one of his famous novels, "Love in the Time of Cholera," there. But Cartagena has a darker side that visitors may not realize: One-third of residents live at or below the poverty line.

Escobar once worked in a maternity clinic in Cartagena, and she was devastated when a 12-day-old baby died in her arms. It was heartbreaking, Escobar said, even more so when she found out that the baby's teenage mother couldn't afford $30 for treatment that could have saved the baby's life.

"His mother (needed) $30 that I had in my pocket. I will never forget that," she said. "It was a preventable death."

To break the cycle of poverty and infant deaths, she started the Juan Felipe Gomez Foundation, which is helping young mothers in Cartagena. Since 2002, her foundation has provided counseling, education and job training to more than 2,000 teenage mothers. And in 2005, she established a medical clinic that has provided health care to more than 84,000 low-income people -- mostly young mothers and their children.

"You see these girls, (with) their tiny faces ... they're babies holding babies," Escobar said.

What role does race play?

Colombia has a much higher infant mortality rate than the United States as a whole, but not when you examine the vast differences among racial groups in the U.S.

CDC data spanning from 2006 to 2008 show that black Americans in Hawaii, Indiana, Ohio, Tennessee and Wisconsin all have infant mortality rates above 15 per 1,000 live births. This racial disparity is very much present in Mississippi, too, where the rate over that period was 7.07 for white children compared with 13.82 for black children.

"It is my belief that is largely due to poverty and the social determinants of health," Currier said about this divide.

In Mississippi, 40% of infants are born to black women, which could be driving up the infant mortality rate for the state as a whole, Lackritz said. Black women are also 50% more likely to give birth to a premature baby, and no one knows why, the CDC says.

These demographic observations don't have to do with skin pigment, Lackritz said, but rather associated factors such as poverty, low socioeconomic background and teen births.

The disparities seem to persist even taking into account health conditions such as diabetes and obesity, Owens said. There is even evidence, including a study from Morehouse School of Medicine, that black women with college degrees have a higher likelihood of preterm birth and low birth weight than white women with college degrees.

It's unknown whether there are genetic factors that come into play, or if there are higher rates of inflammation or infection among blacks linked to pregnancy complications. There might be an interaction between a person's genetic disposition and exposure to stress that could lead to preterm births, Lackritz said.

There could be environmental factors, including stress, that certain groups may experience in a different way, Owens said.

"This should be an active area of research," Lackritz said. "This is an area that has not received the sufficient attention that it deserves."

Sudden infant death syndrome