The gender pay gap is significant enough that it's negatively impacting women's retirement savings, according to a survey by T. Rowe Price.

Baby boomer women who were surveyed had a median 401(k) savings balance of $59,000, compared with $138,000 for baby boomer men. 

Millennial women are trending the same way, with a median 401(k) balance that is about $30,000 less than those held by men, according to the survey.

The disparity appears to be at least partly due to pay levels, with surveyed women earning almost $27,000 less in median annual income than men respondents.

Women also, on average, contribute less to their 401(k) than men, and 66 percent of female respondents who are contributing to their accounts below recommended levels said they are putting in as much as they can afford.

These women, the survey found, are also significantly less likely to be saving for retirement in accounts outside of their 401(k)s compared to men. Ten percent say they use other savings vehicles, compared with 32 percent of men.

The survey’s findings also indicates a comparable percent of men and women continue to work after retirement, women are most likely to say they continue to work because they need the money. Men are most likely to say it's for mental stimulation.

Forty-six percent of women are more likely to believe they will have to reduce their standard of living in retirement, compared with 37 percent of men, and 33 percent of women were either widowed or divorced within the first five to 10 years of retirement compared with 17 percent of men, according to the survey. Beyond the first 10 years, the number of single or divorced women increased to 45 percent, while the number of men barely changed at 18 percent.

The survey focused on 3,005 adults age 21 and older who have never retired and are contributing to a 401(k) plan or are eligible to contribute and have an account balance of at least $1,000, and 1,005 retirees who have a rollo-ver IRA or left-in-plan 401(k) balance.