Millennial women are still saving less than their counterparts in their 401(k)s and remain less confident about that they will have enough funds once they retire.

The average 401(k) balance for women is $38,000, compared with men who have an average balance of $74,000, according to data from T. Rowe Price.

The biggest factor is the gender pay gap: In 2015, women earned 83% of what men earned, according to a Pew Research Center analysis of median hourly earnings of both full- and part-time U.S. workers.

Based on this estimate, it would take an extra 44 days of work for women to earn what men did in 2015, said Robert Johnson, president of The American College of Financial Services in Bryn Mawr, Pa.

Another large contributing factor is that wages have not increased for more than a decade. After paying for expenses such as rent and auto loans, it means someone who receives a salary of $40,000 would have only about $958 a month to live on to pay for food, student loan payments and entertainment, said Bill DeShurko, president of 401 Advisor, a registered investment advisory in Centerville, Ohio.

While wages tend to increase by the time people turn 35, the probability of higher expenses increases as well, because many people will have a mortgage and a family, he added.

"There is a lack of optimism in this group that will only be rectified with years of strong economic growth and solid wage appreciation," he said. "This is a live-for-today generation."

Many Millennial employees, including women, do not understand that the company match in their 401(k) plan can easily add tens of thousands of dollars to a retirement portfolio.

"Many people don't understand that it is 'free' money, as no one has ever explained it to them," said Krista Hall, a financial adviser for Hefty Wealth Partners in Auburn, Ind. "I do think increased education would be beneficial."

A recent survey from Schwab Retirement Plan Services of people 25 to 35 years old who participate in a 401(k) plan found that female Millennials report uncertainty related to saving enough for retirement compared to their male counterparts.

The data shows that 55% of Millennial men believe they are saving enough to retire when they want to, compared to 42% of women. The survey also found that only 36% of Millennial women feel totally on top of their 401(k) investments while 55% of Millennial men share the same sentiment.

"A variety of social and economic factors impact the way men and women view money, and our survey showed that this is already affecting the youngest generation of workers," said Catherine Golladay, senior vice president of participant services and administration at Schwab Retirement Plan Services. "It is important for women and men alike to have access to and take advantage of critical resources, such as professional 401(k) advice and financial wellness programs, to help close the gap in retirement savings confidence."

Options to Improve

One of the best ways to improve your retirement balance is to find methods to lower the costs of investing, said Johnson.

"The negative effect of fees compound over time, just like the benefits of compound interest increase over time," he said.

Individuals should also participate to the fullest extent in their employer sponsored retirement plan.

"If the company will match a 6% contribution, make at least a 6% contribution," Johnson said. "Failing to do so is akin to turning down free money.

Millennials need to also take more risk with their investment choices and choose more stocks than cash or CDs which yield little interest.

"If you have a long time horizon, invest in a diversified portfolio of stocks," he said.

The automatic escalation feature offered by many companies is a good option to generate more income. Employees agree to increase their contribution rate by a fixed percentage each year.

"This is a method that enables individuals to save more and helps us overcome our biases toward the present -- that is, it's difficult to deny ourselves consumption in the present to have more consumption in the future," Johnson said. "By agreeing to escalate our savings rate in the future, we get around our propensity to procrastinate and not make that decision."