A new study is making headlines this week. “Early full-term babies may face later school woes” warns HuffPo, explaining that in a study of 128,000 New York City public school kids,
…of the children born at 37 weeks, 2.3 percent had severely poor reading skills and 1.1 percent had at least moderate problems in math. That compares to 1.8 percent and 0.9 percent for the children born at 41 weeks…. Children born at 38 weeks faced only slightly lower risks than those born at 37 weeks… Compared with 41-weekers, children born at 37 weeks faced a 33 percent increased chance of having severe reading difficulty in third grade, and a 19 percent greater chance of having moderate problems in math.
This isn’t great news for those of us with babies born a tad early – one of my kids came at 39 weeks, and the other at 38 and change because I had an underachieving placenta in both pregnancies – and of course, the study is being used to basically blame moms for their selfish desire to hasten delivery or agree to scheduled c-sections which work in their OB’s favor.
The study authors were more thorough than what we typically see in infant feeding research, controlling for confounding factors like smoking, lack of prenatal care, and poverty, as well as gestational weight, so on the surface, it is rather hard to explain away these results.
And yet, since I can’t find the actual study (just the media reports), I’m unclear if the researchers factored in why the babies were delivered a bit early, and how their pregnancies were, in general. Were the moms on any medications? Did they exercise? What about prenatal stress? Depression during pregnancy? These are all factors which might be associated with preterm labor and delivery, and possibly could be affecting attention span or some other psychological or neurological characteristics. (Speaking of which – let’s remember that test taking skills have little to do with intelligence, and only matter for academic success, not lifetime success.)
But even if we take the findings as they are, and accept that being born a bit early may have an impact on your future academic success, we need to understand what this means in context. First of all, we’re talking about incremental disadvantages. 2.3 percent versus 1.8 percent. That means that even if you are in the group of kids born a few weeks early, you still only have a 2.3 percent risk of having “severely poor reading skills”. If we take 100 kids born between 37-38 weeks, this means only between 2 and 3 of those kids will be suffering from this adverse effect.
Now, compare this to the risks shown with late-term delivery. A study back in May claimed that babies born at 42 weeks
had “more than twice the risk” of developing ADHD. Another study
claims that the risk of stillbirth is 1/926 at 40 weeks, 1/826 at 41 weeks, and 1/760 at 42 weeks – in other words, with every week, the risk of fetal death increases. Ingesting meconium gets more likely the later your baby is delivered – there has been a 4-fold decrease
in the amount of babies suffering from meconium aspiration syndrome since US doctors started inducing pregnancies before they went too far past-term.
These stats are not meant to freak anyone out – I only cite them as a way of showing that we need to consider context when we look at statistics and studies. There are risks with delivering too late, and risks with delivering too early. The lesson should probably be that if you get to choose when your baby comes, your best bet is to plan for around 40 weeks, barring any medical issues that might make an earlier delivery a better choice. If baby decides to come early or doesn’t want to leave, then you and your doctor have to do some careful considering of your options, based on your individual case. Revolutionary idea, isn’t it?
Unfortunately, in the case of this study, rather than simply stating the facts and perhaps giving a bit of toned-down commentary that explained to women that inducing early may not be the best idea unless there is a medical reason to do so, the media pundits got alarmist and judgmental. A pediatrics professor/neonatologist interviewed for the HuffPo article lamented that “There are still a lot of babies who are being delivered more or less electively at 37 and 38 weeks, with people thinking, `This is no big deal – these babies are full-term.’ I think this is a big deal….I don’t want to panic moms whose babies come at 37 weeks…But those elective early deliveries really need to stop.”
This may be true. After having two babies induced early, I can attest that there are other issues that arise when a baby is forcibly evicted before the lease is up. But we also need to be careful about overstating things. A tiny little decrease in the ability to take tests is hardly a “big deal”, especially when I suspect most early deliveries are not “elective”. Many doctors do choose to induce or perform c-sections at 39 weeks, and maybe that should stop… but I don’t think it’s the moms who are making these calls. So maybe the focus should be on influencing the American Academy of Obstetricians and Gynecologists rather than engaging in subtle barbs towards these mythical moms who “can’t be bothered” to stay pregnant.
I know it seems odd that I’m posting about this, a study which has nothing at all to do with infant feeding, but think about it: you could easily sub out the term “elective early delivery” with “formula feeding” and the study would look and sound all too familiar. Without a strong understanding of relative risk and a healthy dose of perspective, it’s far too easy to use studies to scare women and create misunderstandings which will later be used to back up inflated claims. The more we learn to approach parenting science with a critical eye, the better off we will all be – no matter what our feelings about infant feeding.
A little post-script:
When I was looking for the actual study published in Pediatrics, I stumbled across another study in that same journal that we surprisingly (said with sarcasm) have not heard about in the parenting media. In the June issue of Pediatrics, researchers found that
…maternal cigarette smoking correlated significantly with the development of NEC (P = 0.02). There was no correlation seen between maternal gestational diabetes, maternal hypertension, formula feeding, and pathologic chorioamnionitis or uteroplacental insufficiency and NEC.
“These data identified maternal cigarette smoking as the only risk factor that is associated with the development of NEC in premature infants,” the authors write. “Our data imply that smoking delivers toxins and nicotine to the uterine microenvironment that can affect microvascular development and may predispose the fetus to future NEC.”
Huh. I thought formula feeding was the BIGGEST reason babies got NEC.
So finding no correlation between formula feeding and a higher risk is actually big news. More importantly, knowing that smoking is a major risk factor could actually help prevent infant death. Seems a bit more important than testing well in grade school, but maybe that’s just my own bias….