See more of our coverage on recent attacks against Planned Parenthood here.

Planned Parenthood plays a critical role in providing contraception to low-income women in America and is sometimes the only safety net family planning provider available, according to a new analysis.

The Guttmacher Institute performed the analysis of data from 2010, the most recent year available, at the request of the Congressional Budget Office (CBO). The CBO wanted information on places where Planned Parenthood is the only option for low-cost family planning services.

There are quite a few such places, the analysis found.

In one-fifth of the 491 counties in which Planned Parenthood centers are located, a Planned Parenthood site is the only safety net family planning center available. In two-thirds of those 491 counties, Planned Parenthood serves at least half of the women who get their contraception from safety net health centers.

Planned Parenthood also serves a disproportionate number of the nation’s low-income women. Planned Parenthood centers make up just 10 percent of all publicly supported safety net family planning centers, yet they serve 36 percent of low-income women who get their contraception from safety net clinics.

That’s more than other types of providers, the analysis found: “By contrast, centers operated by health departments serve 27 percent of safety-net contraceptive clients, FQHCs [federally qualified health centers] serve 16 percent, sites operated by hospitals serve 8 percent, and sites operated by other agencies serve 13 percent.”

These numbers reveal one problem with recent arguments from Republicans who want to defund Planned Parenthood and divert those funds to other health centers. They claim that there are a lot more community health centers that offer women’s health care than there are Planned Parenthood locations, and so it wouldn’t harm women’s health if Planned Parenthood went away and the funds went elsewhere.

But these lawmakers consistently ignore the issue of patient load. There may be more locations of other safety net family planning clinics than there are Planned Parenthood sites, but those clinics don’t serve nearly as many patients as Planned Parenthood does, and would likely be overwhelmed if their patient load suddenly surged.

The quality of services is also a major issue, the analysis found.

The level of care provided at non-Planned Parenthood family planning clinics is dependent on a variety of factors, including state budgets, capacity, and targeted regulation of abortion providers (TRAP) legislation. Texas, for example, experienced a significant drop in family planning patients after cutting its funding by two-thirds in 2011.

Planned Parenthood is unmatched at offering same-day appointments, has three times shorter waits than other safety net clinics, and is much more likely to offer a broad range of contraceptive services, according to the analysis. Ninety-one percent of Planned Parenthood health centers, compared to 48-53 percent of other sites, offer at least ten of 13 reversible contraceptive methods.

There’s also the problem of what to do with the many dozens of counties who have nowhere else than a Planned Parenthood for low-income people to go for family planning services.

“Certainly in the short term, it is doubtful that other providers could step up in a timely way to absorb the millions of women suddenly left without their preferred source of care and whether those providers could offer the same degree of accessible, quality contraceptive care offered by Planned Parenthood,” the analysis notes.