Only 23% of workers in the US have access to paid family leave through their employers. Without enough pay, many return to work within weeks of giving birth or adopting. Research has shown that laws that increase access to paid leave resulted in better health for birthing people and babies. But while it benefits economic security and health, paid leave is not equally available.

Forty percent of workers in the highest paid jobs have paid family leave benefits, compared to only 7% in the lowest paid jobs. Because racism impacts employment and economic opportunities, Black women and other people of color more likely to have low-wage, part-time and shift work jobs, with a lower likelihood of workplace protections.

In 2017, San Francisco implemented the first fully paid leave law in the US. The law requires that most private sector employers in the city make up the difference from what California’s partially funded leave program offers, so workers have 100% wage replacement for 6 weeks after the birth of a child. New research using birth certificates and hospital records investigated whether the paid leave ordinance was associated with improved birth outcomes.

The results indicate that San Francisco’s policy had little effect on birthweight, gestational age at birth, and related outcomes. While the policy was intended to benefit low-income families who might not have been able to take advantage of programs that only paid partial wages during leave, research has shown that it may not have reached low-income pregnant people. By limiting coverage to firms with at least 20 employees, low-income workers and workers of color were disproportionately excluded from the policy. Those workers were also less likely to have received information about the policy from their employers.

Despite the intended focus on low-wage workers, the policy may have improved leave for higher wage workers who already had access, potentially making health inequities worse. Unlike San Francisco’s policy, California’s paid family leave program with partial wage replacement doubled use of maternity leave from about 3 to 6 weeks, with strongest impacts among Black, non-college educated, unmarried and Latinx birthing people. That might be because California’s program covers almost all formal private sector workers. Overall, 2/3 of pregnant people with Medicaid in San Francisco worked during their pregnancies, and only 1/3 of them were eligible for the city’s paid leave coverage.

These results indicate that future prenatal and postnatal leave programs should be designed with an equity approach to reach birthing people most in need of economic and employment supports. Ideas for policies to advance health equity include requiring that wage replacement rates are high enough that low-income workers can afford to take time off, upholding job protections, increasing coverage for part-time and variable work, and increasing campaigns to improve knowledge and uptake among marginalized communities. Taking an explicit equity approach means acknowledging how structural factors make it harder to access time off during and after pregnancy. To ensure future expansions of paid family leave reach the people they’re intended to help and don’t make inequities worse, policymakers need to focus on issues that could limit access, like coverage and eligibility restrictions and limited public awareness.