People driving the longest distances to get an abortion are more likely to come from congressional districts with lower incomes and more diverse populations, according to data analysis by the left-leaning Center for American Progress provided exclusively to Axios.

Why it matters: The steep and disproportionate barriers to reproductive access in the post-Roe era are becoming more measurable.

• "Women deserve access to care, and it shouldn't be on a basis of their income," said Sara Estep, associate director of the Women's Initiative at CAP, who conducted the district-level analysis of data through September.
• An extended trip could mean lost wages coupled with expenses for gas, lodging and child care (a majority of abortion patients are already parents).
• Those costs "are almost like another ban," said Stacey Lee, a Johns Hopkins Carey Business School professor of ethics and health law.

State of play: Out-of-state travel for abortion surged after Roe was overturned and states implemented their own bans or protections.

• States bordering those with strict abortion limits saw big increases, such as Illinois and Florida.

More recently, states in the U.S. southwest and southeast considered safer havens for abortion implemented some of the nation's strictest bans.

• Florida's State Supreme Court earlier this month cleared the way for a 6-week ban to take effect May 1. In Arizona, the state's high court upheld a near-total abortion ban. The states are some of at least a dozen that will or are seeking to have abortion questions on their November ballot.
• People seeking an abortion in those states are expected to travel even further. In Florida's case, that could look like driving to North Carolina or Virginia.

By the numbers: People who are more likely to drive eight hours round trip to access an abortion make about $4,000 less annually than those with shorter driving times, per CAP.

• Districts with high shares of Black women had an average one-way driving time of 30 minutes longer than those with lower shares.
• Districts with high shares of Hispanic women had an average driving time of one hour longer than those with lower shares.
• In districts with Republican representatives, driving time is on average two times longer than those in districts with Democratic representatives, per CAP.

Between the lines: Driving distance has become a significant factor in whether or not someone can choose to become a mother, Lee said.

• They might consider: "If I can't drive 100 miles, if I can't afford a bus ticket or a train ticket, then I am essentially forced to have this child."
• Lower-income workers are also less likely to have paid sick leave through employers.
• "One of the biggest drivers in helping women to increase their financial independence, to access or increase their career advantages, is the ability to control when you become a mother," Lee said.

Friction point: Providers in some states require patients to visit a clinic more than once before receiving an abortion.

• The Brigid Alliance, which helps coordinate travel stipends for people receiving abortions, has coordinated trips of increased distances and seen associated costs increase, said Serra Sippel, interim executive director.
• Those circumstances add pressure to people "already facing strains when it comes to financial status, family situation and housing," Sippel said.

Go deeper: Charted: Young adult sterilization soars post-Roe v. Wade