According to recent studies, floods can influence a person’s health even before they are born. These findings will be shared on Tuesday, December 10, at the AGU’s 2024 Annual Meeting in Washington, D.C.
A comprehensive analysis of over 3,000 studies conducted worldwide has revealed that flooding is associated with a roughly 3% rise in preterm births globally. Additionally, infants who experience floods while in utero are more likely to have a lower birth weight. These two factors are linked to a higher risk of chronic health issues like asthma and diabetes later in life.
Although the research did not specifically identify the biological reasons behind the increased preterm births or lower birth weights due to flooding, existing studies on various disasters suggest that stress, interruptions in daily life, and difficulty accessing healthcare may contribute to these outcomes.
Julia Gohlke, an environmental health researcher from Virginia Tech and the lead author of this study, stated that flooding “has lasting effects.” With climate change exacerbating flooding incidents, this research aims to provide a clearer understanding of the potential ramifications involved.
Rising waters lead to reduced birth weights
Floods can directly affect human health by causing injuries or fatalities and can also spread illnesses. Additionally, there are indirect health implications, such as ongoing stress and economic loss. However, researchers are still striving to grasp the complete range of negative health effects that floods can impose. While some studies have indicated that floods may worsen pregnancy outcomes, findings have varied significantly.
To clarify the effects of flooding on pregnancy, Gohlke and her team assessed data from 3,177 studies that examined the relationships between flooding, pregnancy duration, and birth weight from the 1800s to today. The data exhibited substantial variability across different floods and locations: while some investigations reported no effect from flooding on pregnancy, others presented strong evidence that flooding heightens the risk of pregnancy and birth complications. For instance, a 2008 study related to Hurricane Katrina found that flooding contributed to a nearly 230% increase in preterm births.
Through their research, the scientists concluded that any flood generally causes a 3% rise in preterm births compared to areas that did not experience flooding. Furthermore, approximately 7% more infants exposed to floods in utero were recorded as having low birth weights.
Stress impacts can persist
According to Gohlke, flooding may lead to early labor and lower birth weights for multiple reasons. Stress can trigger early labor; for instance, extreme heat is linked to an increase in preterm births, possibly due to dehydration. Similar scenarios may occur during floods if water supplies are compromised or individuals are forced to traverse long distances to escape hazardous conditions, as seen in North Carolina during Hurricane Helene this September.
Furthermore, early deliveries may occur during floods when individuals cannot reach healthcare services in time. Access to medical care can help prevent preterm labor, yet flooded or damaged roads may hinder timely support.
While low birth weights often correlate with preterm births, this isn’t universally true, Gohlke noted. Pregnant individuals who experience reduced food intake can also give birth to smaller babies, regardless of their delivery timing. As flooding can disrupt access to food — through crop devastation or blocked supply routes — pregnant women during such events may face a higher likelihood of delivering lower-weight infants.
Although preterm births and low birth weights do not necessarily mean that a child will have developmental issues, obesity, or diabetes later in life, they do raise the risk factors. Therefore, during flooding events, emergency services should prioritize the evacuation of pregnant individuals.
