Longevity. Leaving work to care for kids or parents. Earning less.
These are the headwinds most talked about among women when it comes to the retirement challenges many of them face.
Women have retirement balances that are half the size of men's, according to data from the Vanguard Center for Investor Research. Both genders participate in workplace savings plans at similar rates — although women are more likely to use the plans, and they save more, as well.
Vanguard found, when controlling for income, that the difference in balances is due to men's higher wages.
There's still cause for concern. One in 5 women has nothing saved for retirement, according to the CNBC/SurveyMonkey Women at Work Survey. The national poll of 1,068 working women was conducted Feb. 10-14 by CNBC + Acorns in partnership with SurveyMonkey.
It turns out that women ages 18 to 29 are even likelier to have zero in retirement savings, at 34%. Keep in mind, though, that the youngest members of that age group may not yet be working full-time.
Even though it feels slow, change is happening: More young women are learning about money and teaching others that it's within their grasp to take charge of their finances.
Says Tori Dunlap, a financial coach in Seattle, "I was put on this earth to fight for women's financial rights."
Here's Dunlap's main takeaway: Investing is not scary — at least, it doesn't have to be — and if you want to retire someday, it's essential.
Dunlap, 25, is the founder of Her First $100k, a financial information platform for millennial women, and her mission is to help women get rich.
She takes it seriously, and she doesn't brush away her own privileged past. "I was lucky to have a great financial education from my parents," she said, who helped her graduate from college debt-free. Since she grew up thinking everyone knew how to invest, how to save and how not to take on credit card debt, it was a bit of a shock to find out that a lot of women were clueless.
Even though women are talking more about money, we still have a way to go. "What we're not talking about is the investing gap," Dunlap said.
"The No. 1 fear is [investing] incorrectly," Dunlap said. Speaking as someone who started crushing financial goals early, Dunlap is the voice of financial confidence — and cold hard math — for women.
"You're not going to be able to retire if you don't invest," she said. "If [your money] is sitting in a savings account, it's not going to grow."
Dunlap thinks people are missing the point when they call bubble baths or face masks, which she admits to loving, a form of self-care. They are, in fact, self-soothers. "True self care is hard," Dunlap said. "Things like eating healthy, going to the gym, having hard conversations with friends, setting boundaries, checking in on your money, going to therapy."
Similar to the way ostriches bury their heads in the sand, some women act as if their problems don't exist. They say things like, "Investing is for rich people, so I'm not going to do it," or "I'll do it next year — when I make more money, or when I'm not in debt."
These attitudes can really harm your finances. Investing, frankly, can't wait, says Dunlap. "Get comfortable being uncomfortable," she added. "That's where the real transformation is."
Few people in their 20s worry about saving in general or planning for retirement. Hannah Levy, 33, who does content marketing for startups, luckily got herself in the habit of saving 10% to 15% of her income early on.
But it wasn't until she and her soon-to-be-husband started merging finances that she realized how little she knew, mostly because she hadn't thought about it.
In high school, financial topics and the stock market struck her as boring — and worse, a world that didn't admit women. She describes her parents' household as a traditional one in which her dad made the financial decisions. Money felt inaccessible.
It's a different world now, and Levy, who lives in San Francisco, notices companies like Ellevest and people like Dunlap growing in number. They are essential for women who want to better navigate their finances.
"You need to be exposed to things like how to make your money work for you today, the gender investing gap, like staying in the stock market," Levy said.
Money conversations with friends are more common and feel more natural, and so are places for women to connect online, such as organizations for women in tech. She applauds the initiative of having more women fill board seats.
Levy says the rise in female leaders in business has a tangible impact on women's interest in their own finances: "You can't be what you can't see," she said.
"Women should be talking about investing in the stock market," Levy said. "It doesn't have to feel like we're engaging in a man's space."
Disclosure: NBCUniversal and Comcast Ventures are investors in Acorns.