Hurricane Impacts on Birth Outcomes, with Jacob Hochard

Notable Quotes

• Negative birth outcomes can have lifelong effects: “We find that folks with lower birth weights end up being less likely to form romantic partnerships, are likely to be more neurotic, and are likely to have lower employment rates, lower educational attainment, and lower lifetime earnings. It is an important conditioning factor for the next 60 or potentially 70 or 80 years of your life that’s determined by in-utero development conditions.” (5:15)
• Hurricanes impact more than just the communities that experience dangerous weather: “Tropical storms are devastating for vulnerable populations. We see lower birth weights, higher incidences of preterm births, and higher incidences of low-birth-weight outcomes and very-low-birth-weight outcomes … Birth outcomes and impairments were experienced clear across [North Carolina], not only in places that were struck directly by [Hurricane Irene] and that experienced 17 or 18 inches of rainfall and hurricane-force winds, but also in places inland that didn’t necessarily experience the same physical exposures.” (7:57)
• Intergenerational impacts of tropical storms: “When we think about sustainability planning, built infrastructure is an important piece of the social value of society, but there’s also other stocks of capital in economics—things like human capital (our intelligence, our people) and natural capital (like our fluffy beaches that draw tourism). The impacts [of disasters] on these types of resources are also important … We’re looking at not just the impact on a vulnerable population, but also really the intergenerational transfer of that impact, in terms of determining future aptitudes of the next generation.” (19:37)

Top of the Stack

• “Associations of Hurricane Exposure and Forecasting with Impaired Birth Outcomes” by Jacob Hochard, Yuanhao Li, and Nino Abashidze
• “Integrating Nature into US Economic Statistics, with Eli Fenichel” on Resources Radio
• “The Social Value of Predicting Hurricanes” by Renato Molina and Ivan Rudik

The Full Transcript

Margaret A. Walls: Hello and welcome to Resources Radio, a weekly podcast from Resources for the Future. I’m your host, Margaret Walls.

Today we talk with Jake Hochard, who is the Knobloch Assistant Professor of Conservation Economics at the University of Wyoming’s Haub School of Environment and Natural Resources. We’re going to talk with Jake about a recent paper he published that looks at the impacts of hurricanes on birth outcomes. Stay with us.

Jake, hello and welcome to Resources Radio. It’s nice to have you here.

Jacob Hochard: Thank you for having me, Margaret. It’s great to be here.

Margaret A. Walls: We like to start our episodes by asking our guests about how they got into their field of study and research—what inspired you, and what motivated you? Can you tell us about your own journey to becoming a natural resource economist?

Jacob Hochard: It started in undergrad. I was a student at Gettysburg College, where I was studying economics and environmental studies. My other activity at Gettysburg was being a guide for mountaineering, rock climbing, and sea kayaking. I worked for the outdoor program there, and that was my true passion. The degrees were just something I had to accomplish along the way.

In my third year in college, we went out to Colorado for a mountaineering training trip to learn how to be a better guide and learn some technical skills. That was my first time ever going west of the Mississippi, which was a transformative experience. Truth be told, I went to the University of Wyoming to study environmental economics because it was the bridge of what I was already studying and there were amazing mountains in the distance.

Margaret A. Walls: I think a lot of us who are in the environmental field have these sorts of stories in our background.

Jacob Hochard: It’s definitely a decision I don’t regret. For the first year or two of my training as a graduate student, I was in a little over my head, but I began to love the work in my third or fourth year and certainly as my career took off.

Margaret A. Walls: You recently published an article, Jake, that I want to talk about. This is in the journal Nature Communications. It’s coauthored with Yuanhao Li and Nino Abashidze, and it’s titled “Associations of Hurricane Exposure and Forecasting with Impaired Birth Outcomes.”

I like this paper—I like all your work, Jake—but I wanted to have you on to take a deep dive into it. We’re going to talk about the data, the methods, and the key findings, and then I’m going to make you talk about some policy implications of the work and research on hurricane impacts more broadly.

First, let’s get started with a general description of what you set out to look at in the study. What was your overarching research question?

Jacob Hochard: The study was inspired by my first job placement at East Carolina University, a frequent recipient of hurricanes and the academic research on this topic. It’s been a question of interest for a long time. Economists have always been fascinated with the impacts of disasters on vulnerable populations and what we can do about them.

The overarching question here was what effect tropical storms (which we use interchangeably with hurricanes) have on pregnant women who experience impacts during their pregnancy and also what effects there are on the unborn child.

Margaret A. Walls: Why is this particular question important to analyze? There is some research about this that has investigated this connection between various birth outcomes, such as low birth weight or premature births, and then, later in life, health and economic outcomes. Did that motivate you? Can you tell us a bit about that area of work?

Jacob Hochard: The backdrop of this work is this idea of the fetal origins hypothesis, which caught fire in the 1990s and became a well-studied hypothesis. The hypothesis says that the first nine months of development might be more important than the home and the conditions that you’re born into for determining your outcomes later in life.

Since the early ’90s, there has been a ton of research looking at how birth outcomes—things like preterm births, low birth weights, very-low-birth-weight outcomes—influence later-life outcomes both medically and socially. There’s robust evidence showing that if you do have one of these impaired births, there is an increased likelihood that you might develop attention deficit disorder, increased blood pressure, higher rates of breast cancer, or psychiatric disorders. There is evidence that you have lower IQ and a lot of other medical outcomes.

In addition, there have been well-documented social outcomes associated with these initial birth conditions. We find that folks with lower birth weights end up being less likely to form romantic partnerships, are likely to be more neurotic, and are likely to have lower employment rates, lower educational attainment, and lower lifetime earnings. It is an important conditioning factor for the next 60 or potentially 70 or 80 years of your life that’s determined by in-utero development conditions. Where we become interested in is what type of social impacts or natural disasters might affect those development conditions such that you can have drastic consequences later on.

Margaret A. Walls: I did not know there was such a robust literature on that topic on so many different outcomes. It seems like measuring the effect of hurricanes or tropical storms on any kind of health outcome can be statistically difficult—coming up with the methods and the data. Tell us about the data and the methods that you use and, in particular, how you’re able to connect exposure to the hurricane you looked at and the birth outcomes you’re measuring.

Jacob Hochard: We’re not the first to do this. Other authors have focused on the impacts of tropical storm events on birth outcomes, and at this point it’s a well-accepted finding that these tropical storms are going to have adverse consequences on births. The approach to documenting generally relies on vital-statistics data. If you look at birth-outcomes data, which are often recorded by a Department of Health and Human Services in whatever state you’re in, then you can often retrieve those data.

We retrieved those data for North Carolina, going back 20 years or so. Once you have those data, it’s important to then figure out where these women lived, not only when they gave birth, but also when the birth was conceived. We get residential addresses and turn them into points on maps.

Once we have the points on maps, in addition to the conception dates and birth dates, you’re then able to link that up to the storm’s physical effects. We work closely with atmospheric scientists who do a good job at predicting the rainfall that occurred after a storm event. In our particular paper, we’re focusing on Hurricane Irene, which was a devastating storm for the state of North Carolina.

Margaret A. Walls: What are some of the key findings that you got in the paper?

Jacob Hochard: The initial finding is that we are able to replicate what others have shown in the past: tropical storms are devastating for vulnerable populations. We see lower birth weights, higher incidences of preterm births, and higher incidences of low-birth-weight outcomes and very-low-birth-weight outcomes.

This is not terribly surprising. The question and observation that we found interesting, though, was that all of these birth outcomes and impairments were experienced clear across the state, not only in places that were struck directly by the storm and that experienced 17 or 18 inches of rainfall and hurricane-force winds, but also in places inland that didn’t necessarily experience the same physical exposures. That made us interested and caused us to go deeper, beyond just a cause-and-effect analysis of, What were the impacts of the storm on birth outcomes?

We went deeper because the prior work that’s been done in this area up until about 2016 or 2018 had chalked this up to being a story of, “We know natural disasters are bad. We know that this vulnerable population suffers, but there’s not much we can do about it, because these storm events are big, broad events and you can’t stop a tropical storm.”

Now that we had evidence that these birth impairments are happening all over the state and are not necessarily linked just to the physical impacts of the storm, we began searching for a mechanism. What was the underlying cause of these observed birth impacts? Prevailing intuition and thought was, These are stressful events, stress has a direct impact on in-utero development, and there’s not much we can do there.

But we were fortunate to have access to a lot of different data sets, so we started to explore alternative hypotheses. One was, Is there water contamination or stir-up of environmental toxins that might get into drinking-water systems and disrupt in-utero development? We investigated that by looking at private well samples that were taken across the state before and after these storm events. We analyzed those in the same way that we analyzed the impacts of these storms on pregnant women, and we don’t find any results. So, it seems unlikely to us that water contamination is the driving result.

We also look at other conditions like socioeconomic factors, such as the likelihood that certain populations have better healthcare services than other populations, and that doesn’t seem to be driving the results either.

The final factor that we looked at was prenatal care. There’s a well-documented relationship between the amount of prenatal care that’s received, access to prenatal care, and the health of birth outcomes. Here, we found that the impact on prenatal care mirrored almost identically and across the entire state the impact on birth outcomes that we see.

Margaret A. Walls: One question comes to mind for me: a storm is a temporary event, so how disruptive can it be in terms of things like missing doctor’s appointments or other kinds of appointments that you might have while you’re pregnant. Did you find that it’s a big enough impact to disrupt those kinds of things?

Jacob Hochard: That’s a good question. We see impacts on two different margins. The first impact we see is that prenatal care begins later in the pregnancy when women are exposed to these hurricane events. This would suggest that there’s a delay in initiating care early on. In addition, we see that the total number of prenatal care appointments throughout the pregnancy also decreases. So, not only do you start later, but you generally don’t make up those lost care appointments.

Margaret A. Walls: Can you put the magnitudes of these effects into any kind of context?

Jacob Hochard: For the prenatal care effects, we see women losing about one prenatal care appointment throughout their pregnancy. What’s interesting about that is it’s not just in the places that ended up being exposed to the storm—not just in the places that were along the eastern seaboard and experienced hurricane winds, but also inland in those places that anticipated exposures.

As it relates to the birth outcomes that we observe, they’re very consistent with other natural disasters and stressful events that we see in the literature. It’s long been known that things like domestic assault during a pregnancy will impair birth outcomes in the same way. Family ruptures, losing a loved one in an unexpected way, and stress from local terrorist attacks all will impact birth outcomes.

With tropical storms, we’re in the same ballpark in terms of magnitude. The difference between those events and this one is that this is driven by information that is sent to the masses to protect us. Instead, there’s a population that is using information that isn’t incorrect, but, when it’s sent out, is fairly uncertain. When that occurs, we suspect households are responding by thinking it’s better to be safe than sorry and canceling prenatal appointments. The impacts of that can be quite devastating.

Margaret A. Walls: Let’s take it to the next step: Do you think these findings have some implications for policy or programs? What are they?

Jacob Hochard: One thing that’s different about our work or at least distinguishes it from previous contributions in this area is that, because we’re able to start to identify the mechanism that underlies this relationship between tropical storm events and birth outcomes, we can start to develop targeted policies. There are two ways to think about this.

The first is that we need more research around when we should be releasing forecasts. From our work, we cannot conclude that we should be delaying these forecasts. We should be waiting until they’re more certain to disseminate that information, because we don’t know how households would respond to a state of ambiguity or a hurricane that’s charging up the eastern seaboard. We know it’s coming, but the National Hurricane Center won’t tell us where and when. That situation could be more stressful than this cone of uncertainty and expecting exposure, so we can’t make that claim, but we certainly think that more research needs to look at the optimal release of these forecasts. When can they do the most good, both in preparing people and also making sure that we don’t cause unnecessary worry?

The second is a low-hanging fruit and a direct outcome of the work that we’ve done. Now that we recognize that this stress and this anticipation could be disrupting healthcare services, there’s an opportunity to work with groups like the American Medical Association and healthcare clinics on establishing best-practice standards. We don’t know who is canceling these appointments. We don’t know if it’s the household or the woman canceling this appointment. We don’t know if it’s the clinician canceling this appointment as they prepare for the storm event, but we could certainly create best-practice standards for waiting until there’s a certain level of certainty in the forecast before those cancellations are made to make sure that we’re not overly eager to cancel appointments that are not made up later.

Margaret A. Walls: That’s a good point. A lot of times, the governor of a state that is getting ready for a hurricane will lock things down. I assume that closes offices—I’ve known of situations where offices will close because of that.

Jacob Hochard: Generally in society, especially when we’re talking about disasters and the protection of the public, we tend to take a very precautionary approach. The better-safe-than-sorry idea is prevalent. As it relates to tropical storms, until the early 2000s—maybe around 2001 or 2002—we used to release a “cone of uncertainty” forecast, which I think a lot of folks have seen on television. As a tropical storm approaches, the cone shows the likelihood of where the eye of the storm might end up.

We used to release those about three days out. Now, over time, we’ve started releasing them five days out. So, although our forecasts are getting better, it’s also the case that, when you release those forecasts earlier, there is inherently more uncertainty. Those are the types of precautionary policies that may have unintended consequences that we haven’t been able to fully grasp.

Margaret A. Walls: I’m going to ask you to go even broader now, Jake. We expect hurricanes are going to get worse with climate change, and the worst storms are predicted to become more frequent. Sea level rise is going to exacerbate storm-surge flooding associated with hurricanes, along with normal tidal flooding.

When thinking about how to address these problems and help people that are living in the riskiest areas, there’s a growing chorus of people in this policy space that are saying that we focus too much on property values. When we are making investments in hazard mitigation, allocating disaster aid, maintaining stormwater infrastructure, all those decisions are often driven by the amount of flood damages avoided. These are higher for higher-valued properties—we seem to be focused on property, not people.

One of the things about your study that I like (and you said there are others out there that have looked at this) and that could be important is the impact on a health outcome; in particular, on these birth outcomes. So, I wanted to ask you to think about a broader policy question: the issue of what we’re focusing on when we think about disaster policy and how research can help inform it. What kind of research would you like to see more of? Do you have thoughts about these issues in the policy world and how we might do things better?

Jacob Hochard: I think you’re spot-on. The majority of the work in this area does focus on built infrastructure: our houses, hospitals, schools, and, certainly, military bases. Part of the reason is because infrastructure is historically the low-hanging fruit, and it’s very important, but it’s also relatively easy to value and assess the impacts in a monetary way.

However, I know you had Eli Fenichel on not long ago. When we think about sustainability planning, built infrastructure is an important piece of the social value of society, but there’s also other stocks of capital in economics—things like human capital (our intelligence, our people) and natural capital (like our fluffy beaches that draw tourism). The impacts on these types of resources are also important.

That’s where I would nest this type of work, where we’re looking at not just the impact on a vulnerable population, but also really the intergenerational transfer of that impact, in terms of determining future aptitudes of the next generation. When we think about human capital, we do start to think about our productivity as a society in a much more pointed way, which is why I’m interested in it.

In terms of future research, there are a lot of lessons to be learned about how we’ve analyzed housing prices and public investments into adaptation projects such as seawalls and levies and how that work played out. Then, we can map that onto this more nuanced human-capital research.

One case that comes to mind is the city of Norfolk, which is embarking on a $1.8-billion expansion of their existing seawall. One thing we’ve learned about these public investments is that they’re often targeted at specific communities and locally funded. The communities that can fund them sometimes tend to have more means than the neighboring communities that don’t have a coastal-adaptation war chest ready to build an expensive seawall. In some cases, we see that storm-surge water can smash into those seawalls and then get deflected into neighboring communities that usually have lower-income, less resilient, and minority populations.

In the same way we think about coastal adaptation for built infrastructure, we can think about that in terms of human capital. The number one question I get with this study is, “What do people do? How do high-income populations respond to those forecasts compared to low-income populations?”

We spent a lot of time talking with women who were pregnant during Hurricane Matthew when I was at East Carolina. Higher-income folks tend to take a vacation to Asheville, North Carolina, whereas lower-income populations don’t have that luxury; they can’t afford it or can’t get time off from work. So, I think figuring out ways to support the most vulnerable populations is where future research should be directed.

Margaret A. Walls: That’s a good point about the opportunities that people have to escape. I’ve witnessed that myself.

Jake, it’s been great talking to you about this work. I encourage everybody to read your paper. We’ll include a link to it, but we usually like to end our podcast with a more personal touch: by asking what’s at the top of your stack. That can be something you might be reading right now or something you’re really taken with. Maybe it was a movie or a podcast. Tell us about what’s at the top of your stack.

Jacob Hochard: I’ll mention a paper I just started reading, which is fresh off the press (and maybe not even on the press yet; it’s a publicly available working paper) and by Renato Molina, who’s at the University of Miami, and Ivan Rudik, who’s at Cornell. They examine a similar question to what we’ve studied in a very different way, which I find really intriguing.

The title of that paper is “The Social Value of Predicting Hurricanes.” Their approach is disaggregating the error that’s built into historical forecasts around hurricanes and then examining how public expenditures both before and after a hurricane has come through a community relate to the initial accuracy of that forecast.

That approach is desirable for a few reasons. One, it’s generalizable well beyond North Carolina—it’s generalizable for many storms, and it also has a direct link to investing in or at least analyzing the benefits of these forecasting systems. Over time, these forecasts are getting much better. Our work certainly shows that a good forecast can really have tremendous social benefits—even those that escape monetary metrics.

But Ivan and Renato’s work show that increased forecasts can also pay for the extra research, development, and effort that goes into building these atmospheric science models and leveraging them for early warning systems. Moving forward, that type of work is important. How can we assess the value of these public warning systems in a rigorous way and make sure that public investments are made to support those types of efforts?

Margaret A. Walls: That’s great. I’ll be on the lookout for that paper and, knowing both of those guys, I’m sure it’s interesting.

All right, Jake, thank you so much. It’s been a pleasure having you here. I appreciate you coming on the show.

Jacob Hochard: Thank you, Margaret. I enjoyed being here.

Margaret A. Walls: You’ve been listening to Resources Radio, a podcast from Resources for the Future. If you have a minute, we’d really appreciate you leaving us a rating or comment on your podcast platform of choice. Also, feel free to send us your suggestions for future episodes.

This podcast is made possible with the generous financial support of our listeners. You can help us continue producing these kinds of discussions on the topics that you care about by making a donation to Resources for the Future online at rff.org/donate.

RFF is an independent, nonprofit research institution in Washington, DC. Our mission is to improve our environmental, energy, and natural resource decisions through impartial economic research and policy engagement. The views expressed on this podcast are solely those of the podcast guests and may differ from those of RFF experts, its officers, or its directors. RFF does not take positions on specific legislative proposals.

Resources Radio is produced by Elizabeth Wason, with music by Daniel Raimi. Join us next week for another episode.