A highly publicized study published in the Journal of the American Medical Association that estimated there have been 64,565 pregnancies resulting from rape in states with near-total abortion bans has raised questions about its methodology since its publication last week.

The study’s lead researcher was Planned Parenthood of Montana’s medical director, Dr. Samuel Dickman. According to the study, it was conducted “to assess how abortion bans affected survivors of rape.” Yet, the research did not use any data about rapes, pregnancies, or pregnancies from rapes collected during the times in which the pro-life laws were in effect.

“To our knowledge, no recent reliable state-level data on completed vaginal rapes … are available,” the authors explained.

The researchers instead used surveys from the Centers for Disease Control and Prevention from 2016 to 2017 to estimate how many rapes were likely to have occurred nationally since the abortion restrictions went into effect. They then used data from the Bureau of Justice Statistics to estimate what fraction of those survivors would likely be female victims between the ages of 15 and 45 at the national level.

Because neither of these sources break information down by state, the researchers then looked to the Federal Bureau of Investigation’s 2019 Uniform Crime Reports on rapes. They assume that this data underreports rapes but use this information to estimate the proportion of rapes in a given state.

Using this data, the researchers estimated how many rapes would have likely occurred in states with abortion bans. The researchers estimate that about 12.5% of the rapes would likely have led to pregnancy, which brought them to estimate 64,565 rape-related pregnancies in the 14 states with near total abortion bans between July 1, 2022, and Jan. 1, 2024. 

“Our estimates have several limitations,” the authors acknowledged. “Most importantly, limited reliable information is available on rape victimization and rape-induced pregnancy.”

Some academics CNA interviewed said these “limitations” call into question the reliability of the study’s conclusions.

Michael New, a senior associate scholar at the pro-life Charlotte Lozier Institute and professor at the Catholic University of America, told CNA that estimates about the number of rapes in the country and the percentage of rapes that result in pregnancy vary from study to study. He said the CDC estimates are “much higher than the others,” while the criminal reports to police that are in the FBI numbers are “an undercount.”

New noted in an article in National Review that if one extrapolates the calculations in this study nationally for 2017, it would suggest that “10% of all abortions were performed on rape victims” if half of the rape victims received an abortion. Yet he noted that multiple surveys from the pro-abortion Guttmacher Institute found that rape victims only account for 1% of abortions.

Normally, New said, a study would provide “high-end estimates” and “low-end estimates,” but the researchers in question “just assume that the high estimates are the best ones.”

New referenced the primary researcher’s affiliation with Planned Parenthood and said the study appears to be “advocacy-type research.”

“Academic journals … shouldn’t serve as mouthpieces for pro-abortion activists,” New said. 

Ryan Burge, a statistician and associate professor of political science at Eastern Illinois University, told CNA that rape in the United States is “too prevalent but still very rare” and trying to estimate the number of pregnancies caused by rape in this way is creating an estimate of “a rare event inside a rare event.”

“Making an estimate of something like this is incredibly hard even when it’s not so hotly contested,” Burge explained.

He added: “I don’t think there’s ever going to be an effective way to get at this number — not in a way that would give me a ton of confidence that it’s correct.”

Burge noted that every number used in the study to bring about its conclusion is “an educated guess,” which “all have uncertainty estimates.” He said “there’s a demand for an estimate” and “the public wants to know” but studies that try to make estimates in this way “might not be as academically rigorous as we want them to be” and “don’t meet the highest quality standards that we would expect.” 

“There’s so many questions at every step of this process,” Burge said.

CNA reached out to Dickman, the lead researcher, for comment but did not receive a response by the time of publication. Dickman is an abortionist who is involved in several lawsuits challenging Montana’s pro-life laws.