A recent study in the journal Obstetrics & Gynecology found that homicide is the leading cause of death among pregnant women and women who are six weeks postpartum. Indeed, homicide exceeds other leading causes of maternal mortality by more than twofold.

In many cases, it seems, the pregnancy is the reason for the violence. One of the most troubling findings of the study is that pregnant Black women are eight times more likely to be killed by their intimate partner than non-pregnant Black women.

It’s important to note that the vast majority of these homicides are committed in the homes of these pregnant women. In other words, we are talking about domestic violence, and Black women generally suffer domestic violence at a higher rate than white women. The authors speculate that systemic racism may be to blame for these deaths, and specifically that Black women are not being screened for domestic violence at their medical appointments at the same rate as white women.

“These data highlight broad societal failures,” Aaron Kivisto, a clinical psychologist at the University of Indianapolis and one of the authors, explained. He cited “perceived racism during prenatal health care encounters, which impedes Black women’s access to consistent, quality prenatal care; and heightened rates of unwanted pregnancy among younger Black women, which is linked to partner conflict, stress and violence.”

The past few years have seen significant public discussion about high maternal mortality rates among Black women overall, which some researchers and policymakers believe is the result of Black women’s concerns not being taken seriously by health care professionals.

Inasmuch as this is the case, it should be addressed.

Separately, a women who works at a domestic violence shelter in Dallas told me that Black women may be less likely to reach out for help due to a sense of shame in telling other people, especially white people, that they are the victims of such violence. She also noted that Black women are sometimes reluctant to call the police because they fear that their boyfriends or husbands will be arrested “and then the women will have no way to put food on their tables.”

These are all reasonable explanations for the disparities in violence.

But they still leave a nagging and pressing question about why pregnant Black women are more at risk. In order to understand this disturbing trend, and help save lives, we may need to understand why someone would not want a child to be born.

Children obviously represent a significant change in a relationship between a man and a woman. It’s possible that a man might resent that change. But then why don’t we see the same kind of gap in the homicide rate between pregnant women of all backgrounds?

This is where multiple-partner fertility may also be an important data point worthy of further investigation. Census data suggests large demographic disparities in this regard. And added sexual partners can increase feelings of jealousy, instability and potential violence. We know, for example, that children growing up with a non-relative male are 11 times more likely to suffer abuse than children growing up with their two married biological parents. It would not be surprising if the same emotional volatility that makes men dangerous to children who are not biologically related to them also makes such men dangerous to women who are carrying other men’s children or whom they suspect are carrying other men’s children.

Additionally, men of any race who have moved on to other partners may see a previous partner’s pregnancy as a hindrance to their new relationship.

While there are plenty of news stories to support this kind of inquiry — and I’m arguing that this subject deserves more research for the sake of saving lives — it’s hard to make definitive statements about what is causing these homicides based on the studies we have seen so far. One reason is the lack of research about the perpetrators of these crimes. Seeing domestic violence as only a public health crisis rather than as the crime it so clearly is blinds us to some important realities.

Sure, it would be great if more women of all backgrounds sought help when their relationships turned violent. But why do such a high percentage turn violent? Unfortunately, this kind of blindness to who is committing crimes against women — and why — seems to be more common in recent years. The way we talk about the “missing and murdered” women in this country suggests that we don’t know who is responsible for these tragedies.

The evidence, however, suggests that women are being victimized by the people closest to them. And until we understand what motivates those crimes and the circumstances — which likely include extramarital births and multiple-partner fertility — our ability to save the lives of women and children will be significantly hampered.