The effects of mothers’ stress on child development during pregnancy may be low, according to ongoing research by economics professor Sandy Black.

At a lecture Monday, Black discussed her preliminary research on learning how the deaths of parents during the pregnancy of women affect the health of their babies. Black said she and her colleagues used parental death, or bereavement, to study maternal stress because it was easier to control for certain variables such as stress from pain or economic factors.

“[Bereavement] is unlikely to have physical effects like a hurricane or your house falling — that could actually hurt you,” Black said. “It affects people regardless of socioeconomic status, so everyone’s parents are going to die at some point. Of course, it’s not random when they die, and that’s something we’re going to deal with in the paper.”

According to Black, she and her colleagues have found that the deaths of parents from cardiovascular problems, such as a sudden heart attack, have caused the largest number of negative health effects in babies born while their mothers were experiencing stress. Black said they try to focus on how sudden deaths affect maternal stress, because long-standing illnesses can cause variability in the results.

“A lot of problems with other illnesses like cancer are that it’s not a surprise,” Black said. “You could be really stressed for a while. We would really like kind of random deaths, and these are probably the least random.”

Despite the babies having negative health outcomes, such as low birth weight or height, according to Black, these effects are not long term.

“We can rule out large effects,” Black said. “We’re talking about really tiny numbers, and we just don’t have the precision to identify any of that.”

Black gave the lecture to several graduate students and faculty, including economics assistant professor Michael Geruso, who brought up questions about the different factors affecting the research.

“I don’t think this literature does a good job of defining what stress is,” Geruso said.

Economics graduate student Ziwei He said the questions students raised about Black’s research were helpful.

“It’s good for me to see what people are doing right now in this field,” He said. “It might inspire my ideas in the future.”

Black’s lecture was originally set to discuss the effect of abortion availability on young women, but Black changed the topic Friday after deciding the research was not developed enough to present.