By Eleanor Boudreau
http://stream.publicbroadcasting.net/production/mp3/wkno/local-wkno-890081.mp3
Memphis, TN – This story revolves around the number four and the term live birth.' It's going to get a little technical. But it's not that technical. So, stay with me.
A new paper out in the journal Pediatric Reports compares Shelby County to the nation as a whole and finds that we have almost four times as many infants born under 20 weeks gestation. Bryan Williams is the lead author on that paper. He's an associate dean at Georgia State University, but used to be out of the University of Tennessee Health Science Center here in Memphis.
Williams says that number four is so big, so disproportionate, "It leads one to question the veracity of the data."
Infants born under 20 weeks gestation don't survive. Williams says, "These are infants--or fetuses--which in fact have no chance of survival, and it's hard to make the case that in fact they should have got a live birth certificate in the first place."
In his paper Williams removed some of those extremely premature babies from Shelby County's data, so that the distribution of premature births looked a lot more like the nation as a whole. Then Williams recalculated our infant mortality rate and it dropped--dramatically. The rate went from more than 13 infants per 1,000 live births to a number much closer to eight, and much closer to the national average, which is around to seven.
Of course this kind of revisionist mathematics is only legitimate if we never should have counted some of those premature babies in the first place. And here's where the term live birth' comes in.
If a baby is born under 20 weeks gestation, and shows signs of life, under the definition, it's a live birth, and it gets a birth certificate. Then, when that baby dies--which all babies born under 20 weeks do--its death drives-up the infant mortality rate. But if that baby is born without showing signs of life, it's called a fetal death, and that death is never calculated into the county's infant mortality rate.
Williams says determining whether an extremely small, extremely premature baby is born alive is not cut and dry.
"It's a subjective clinical decision. Often of which is made in very chaotic circumstances. So it's up to that clinician. I'm not a clinician, but I've talked to a number of clinicians who say that it is very difficult to determine," Williams said.
That clinician decision is made more often here in Shelby County because we have a high rate of prematurity. And that, Williams says, drives up the infant mortality rate, "Because it increases the frequency of these rather subjective decisions."
But not everyone agrees with Williams' assessment. Doctor Ramasubbareddy Dhanireddy heads up the Newborn Unit at The Regional Medical Center. Most of these clinician decisions about extremely premature babies get made under Dhanireddy's watch.
"We do not give a birth certificate if there is no sign of life after birth," Dhanireddy insists, "I want to make it very clear. If a baby is born and there is no sign of life--whether it's 200g or 800g--those are still births, we do not offer a birth certificate."
I told Dhanireddy, "One person argued to me that there was some subjectivity, you know, it was more of an art than a science if a baby was born alive."
"That's not true," he said.
Before coming to Memphis Dhanireddy worked in Shreveport, before that he worked in D.C. He says through all those moves he saw no difference in the way doctors determined whether a baby was a live birth.'
"So I'm puzzled," Dhanireddy said, "where these arguments are coming that somehow we have a different definition in Shelby County."
Theresa Chapple isn't as puzzled. "What I think happened here is that he compared Shelby County to the United States," she said.
Chapple heads up Shelby County's Fetal Infant Mortality Review. She doesn't think the large number of extremely premature infants Williams noticed is evidence of bad counting: "What would have been more interesting here is if he would have compared Shelby County to another area that was similar to Shelby County--to see--okay, we have four times more than the United States but are we similar to Washington D.C.? Are we similar to the South Side of Chicago?"
"I think it would have gave us a clearer picture of is it over reporting," Chapple continued, "versus a poorer group, a less educated group of people, end up having bad birth outcomes."
There isn't any doubt in Chapple's mind that the latter explanation is the correct one, "I think that's what it is," she said.