So, the state says Flint water crisis did NOT hurt pregnancy outcomes. Now what?
The state health department says it found no significant increases in stillbirths or infant mortality in Flint, following the city's water crisis.
This may be confusing for people in Flint right now, because just last month, a different study came out from two economists, claiming the fertility rate in Flint dropped dramatically because of the water crisis, while fetal deaths went up. That study hasn’t been peer reviewed, and came under some criticism recently.
Now, the state says it looked at pregnancy outcomes, and didn’t find any “significant differences in birth outcomes for the City of Flint when comparing the pre and post water change time periods.”
The Michigan Department of Health and Humans Services doesn’t have a metric that measures a fertility rate, per se. Instead, they track vital records from doctors and hospitals about things like:
- Stillbirths: the death of a fetus that’s at least 20 weeks old and weighs at least 400 grams.
- Preterm birth: when a baby is born before it’s reached 37 weeks of gestation.
- Infant mortality: when a baby dies before his or her first birthday.
One of the state’s methods compared those outcomes from two time periods: July 2012 through December 2013, before the city switched to use the Flint River as its water source, and July 2014 through December 2014, after the switch had been made and Flint’s residents were exposed to greater levels of lead.
Here’s what they found:
- In terms of infant mortality, there were fewer live births and fewer instances of infant mortality (2,121 live births and 25 instances of infant mortality) after the water switch, when compared with the earlier period, which saw 2,328 live births and 29 infant mortality instances. That means the infant mortality rate dropped from 12.35 to 11.79 peer 1000 births after the switch.
- However, that same method found a very small uptick in the stillbirth rate: from 10.65 before the switch, to 11.32 per 1000 live births after it. We’re still talking about pretty small sample sizes here: out of the 2,121 live births in the “after” period, there were 24 stillbirths. The state health department says this is a “non-statistically significant increase.”
- The state also found similar upticks in preterm births (from 14.27% to 15.98%) and low birth weights (which went up from 13.2% to 14.85%) but again, says those increases were not statistically significant.
“What we found, is that there wasn’t a statistically significant difference around the water source change,” says health department spokesperson Angela Minicuci. “That said, there was a small increase, and we don’t want to discount that. We don’t have an exact reason for what that increase was, but we did see. It just wasn’t high enough for us to consider that statistically significant.”
Flint has always been an outlier, she says, when it comes to pregnancy outcomes. “I think the most important thing for Flint parents to understand is that, compared to the rest of the state, both prior to and after the water source switch, Flint consistently has higher rates of stillbirths, preterm births, and low birth weight than compared to the rest of the state.”
Still, many Flint residents say they don’t trust the state when it comes to the water crisis. Minicuci says they don’t have to take the state’s word for it.
“The one thing I would want someone to understand is, we didn’t do this on our own, just as the Michigan Department of Health and Human Services,” she says, citing input from Hurley Medical Center’s Dr. Mona Hana-Attisha and Virginia Tech Professor Marc Edwards, both of whom did independent analysis to uncover the water crisis. “We had other experts in this field review our analysis to tell us whether or not they were comfortable with the direction it was heading, and with the findings we had.”
The state’s now working with the CDC to get these findings ready for peer review, she says.
“I think the state has done a very credible effort to date, but it’s not going to be the last word on the subject,” says Edwards. “As we’ve seen, other groups are looking at the data, and sometimes they will reach different conclusions. So this is unfortunately the messy nature of science: we don’t know things, usually, with 100% certainty.
“We know that harm was done, by definition, because lead can harm the developing fetus. But whether that harm was significant compared to all the other problems in Flint, and whether it can rise to the level where you can conclude that lead exposure was the problem, that’s a completely different matter.”
No one’s arguing whether the lead had bad effects on a fetus, he says. “The question is whether you could detect it with scientific analysis and quantify it, as one group says it has done.”
Dr. Hanna-Attisha, meanwhile, says that while she wasn’t directly involved in the MDHHS findings, the state’s study and the economists' report looked at different variables. “It is very complicated and difficult research which is why it can't be immediately garnered,” she says in an email.
“But I would also once again say, we know lead and other things in this water (TTHM) impact maternal-fetal outcomes and we also know that Flint has worse outcomes than the rest of the state (even before the crisis). So moving forward, we need to do two things 1) get the lead out of everywhere, 2) invest in the public health and societal infrastructure that supports maternal infant health (poverty, access to health care, nutrition, etc.)”