Maternity leave directly improves the health of mothers and babies, strengthens early childhood development, and supports families’ financial stability. The benefits are measurable and well-documented: each additional 10 weeks of paid leave is associated with a 10% lower infant mortality rate, and the advantages extend into breastfeeding rates, mental health, childhood vaccinations, and long-term cognitive development.
Lower Infant and Child Mortality
The most striking evidence for maternity leave comes from its effect on infant survival. A study published in Public Health Reports analyzed data across countries and found that an increase of 10 full-time-equivalent weeks of paid maternal leave was associated with a 10% lower neonatal and infant mortality rate and a 9% lower mortality rate among children under five. This relationship held across different economic contexts, including in non-OECD countries, where the same 10-week increase produced the same 10% reduction.
The mechanism is straightforward. When mothers are home with their newborns, they can monitor feeding, respond to signs of illness, attend medical appointments, and maintain the kind of consistent, attentive care that fragile infants need in their first weeks. Newborns who are sick, premature, or born with complications benefit even more from a parent who isn’t forced to choose between income and caregiving.
Protection Against Postpartum Depression
Whether leave is paid matters as much as whether it exists at all. A 2024 study of women in New York found that mothers with only unpaid leave had 41% higher odds of experiencing postpartum depressive symptoms compared to those with at least some paid leave. Interestingly, there was no significant difference in depression risk between mothers with partially paid and fully paid leave, suggesting that even partial wage replacement offers meaningful protection.
The financial stress of unpaid leave compounds the already intense physical and emotional demands of new parenthood. Mothers on unpaid leave often face pressure to return to work before they’ve recovered, or they stay home but carry mounting anxiety about lost income. Paid leave removes that specific source of strain. For lower-income mothers, the effect is even more pronounced: those in states with the most generous paid leave policies had a 15% lower likelihood of postpartum depression symptoms compared to those in states with little or no coverage.
Higher Breastfeeding Rates
Major health organizations recommend exclusive breastfeeding for the first six months of a baby’s life, but that’s nearly impossible for a mother who returns to work after a few weeks. Paid leave changes the equation. Mothers in states with the most generous paid family leave policies were 9% more likely to still be breastfeeding at six months postpartum compared to those in states with minimal leave.
The gap widens dramatically for low-income families. Among mothers whose deliveries were covered by Medicaid, living in a state with strong paid leave was associated with a 32% greater likelihood of breastfeeding at six months. These are the families least likely to have jobs with pumping accommodations, flexible schedules, or employer-provided leave, so public policy fills a gap that the private market doesn’t.
Better Vaccination and Preventive Care
Babies need a series of vaccinations in their first months of life, and keeping up with that schedule requires a parent who has the time and resources to attend multiple medical appointments. A longitudinal study of 20 low- and middle-income countries found that each additional full-time-equivalent week of paid maternity leave increased coverage of the three-dose DTP vaccine series by roughly 1.4 to 2.2 percentage points per dose. The effect was largest for the third dose, which is the one most commonly missed because it falls later in the schedule, when more mothers have already returned to work.
This pattern points to a simple reality: preventive healthcare for infants depends on a caregiver being available to provide it. When parents are stretched between work obligations and a baby’s medical needs, the appointments that feel less urgent are the first to slip.
Stronger Early Brain Development
The effects of maternity leave reach beyond physical health into how children’s brains develop. Research from NYU and other institutions has found that longer maternal leaves are linked to fewer cognitive and behavioral problems in young children, even after controlling for factors like childcare quality and home environment. Paid leave specifically is associated with better language skills in toddlers and fewer behavioral problems during infancy, particularly among families with less education and fewer economic resources.
One especially notable finding: compared with unpaid leave, paid maternal leave is associated with a distinct pattern of brain activity in infants that may reflect more mature early cognitive functioning. The early months of life are a period of rapid neural development, and the quality of parent-infant interaction during this window has lasting effects. A parent who is present, rested, and not financially desperate is better equipped to provide the kind of responsive, engaged caregiving that supports healthy brain growth.
The Cost to Employers Is Minimal
A common objection to paid leave is that it burdens businesses, but the data doesn’t support that. A National Bureau of Economic Research analysis found that after accounting for wage reimbursements, there were no measurable effects on firm output, labor costs, profitability, or survival when employees took parental leave. The wage bill excluding leave payments showed no statistically significant change. The point estimate was actually slightly negative, meaning costs may have marginally decreased.
One reason is that turnover drops when employees take leave rather than quit. Firms adjust primarily by bringing on temporary hires rather than absorbing a permanent loss of experienced workers. Replacing an employee entirely, with recruiting, hiring, and training costs, is far more expensive than covering a temporary absence. When leave policies encourage workers to return rather than leave the workforce, employers retain institutional knowledge and avoid the disruption of constant turnover.
Impact on Mothers’ Earnings and Work Hours
Paid leave doesn’t just keep mothers in the workforce. It improves their position when they return. An analysis of California’s paid family leave program found that it led to 10 to 17% increases in usual weekly work hours for employed mothers, with evidence that their wage incomes rose by a similar amount. The program did not significantly affect whether mothers were employed at all, suggesting that paid leave’s primary benefit is in helping already-working mothers maintain stronger attachment to their jobs and careers.
Without paid leave, many mothers downshift to part-time work, accept lower-paying positions closer to home, or cycle in and out of the labor force in ways that permanently reduce their lifetime earnings. The “motherhood penalty” in wages is well documented, and paid leave is one of the few policy tools shown to narrow it. When mothers can take adequate time to recover and bond with a newborn without sacrificing their job or seniority, they return on stronger footing.
Who Benefits Most
The benefits of maternity leave are universal, but they concentrate most heavily among families with the fewest resources. Low-income mothers see the largest gains in breastfeeding rates, the sharpest reductions in postpartum depression, and the most significant improvements in their children’s early development. These are also the workers least likely to have access to employer-provided leave. Only about 27% of private-sector workers in the U.S. have access to paid family leave, and that number drops sharply among lower-wage and part-time workers.
This creates a paradox: the families who would benefit most from paid leave are the least likely to have it. Public paid leave programs, like those in California, New Jersey, and a growing number of other states, begin to close that gap. The evidence consistently shows that when leave is available and paid, mothers use it, and outcomes improve across every measure researchers have examined.