EXHIBIT 4.

Associations between US state firearm prohibition laws (2010–18) and pregnancy-associated homicide in the year after policy implementation (2011–19)

	Crude modela		Adjusted modelb
Firearm laws	No. of observations	Pregnancy-associated homicide	No. of observations	Pregnancy-associated homicide	Firearm pregnancy-associated homicide
Prohibition of firearm possession by people convicted of domestic violence misdemeanorc
Relinquishment not required	356	−1.57	311	−1.37	−1.24
Relinquishment required	338	−2.33***	295	−3.74**	−2.48*
Prohibition of firearm possession by people subject to domestic violence–related restraining orderc
Relinquishment not required	318	−0.61	278	−0.58	−0.59
Relinquishment required	380	−1.30***	340	−1.24*	−0.70
Prohibition and relinquishment by people convicted of a domestic violence misdemeanord	210	−0.79*	184	−1.17**	−0.68*
Prohibition and relinquishment by people subject to a domestic violence–related restraining orderd	206	−0.87**	172	0.13	−0.56

SOURCE Authors’ analysis of data on all fifty states from the National Center for Health Statistics, the Census Bureau’s American Community Survey, the US Fish and Wildlife Service, the Centers for Disease Control and Prevention, and legal review. NOTE Pregnancy-associated homicide mortality is deaths per 100,000 live births.

^aIncludes state and year fixed effects only.

^bIncludes state, year, gun homicide and stranger homicide rates, state Medicaid family planning waiver, median household income, income inequality, poverty, gun ownership, and percent of births by maternal race and ethnicity and age during policy implementation year.

^cReference group is state-years without this law.

^dReference group is state-years with the possession prohibition law but no relinquishment law.

^*p < 0.10

^**p < 0.05

^***p < 0.01