Women, Mao Zedong famously observed, hold up half the sky. The Great Helmsman might not have spied the Internet on the horizon, but women are holding up their end when it comes to e-commerce, too.

The number of U.S. women entrepreneurs using B2B e-commerce website Alibaba.com surged 40 percent in 2012, to 1.6 million registered users. While women still only number one third of all U.S. users, and 22 percent worldwide, the gender gap is closing fast. Global growth in female Alibaba users outstripped new registrations by men by 50 percent in the second half of 2012.

The reasons for the surge is fairly obvious. Starting a home-based e-commerce business is relatively easy, relatively inexpensive and doesn’t require clock-punching at a distant office, factory or shopping mall. For women who have bumped up against the glass ceiling, or those struggling to balance the demands of a corporate job with the desire to have children, e-commerce offers an alternative path to career success.

“It gives us a chance to have it all,” says Julie Degnan, founder of Cakes and Kids, a San Francisco Bay area company that sells children’s party supplies. “Women used to have to choose: am I going to be a mom or a career woman? The fact that you can run a successful business from home and still be a mom and a wife has changed things immensely.”

A mother of three school-age children, Degnan in 2010 returned from maternity leave to find her services no longer required. It was one of six layoffs she endured, the final career hiatus inspiring her to start a business that put her skills as a cake decorator and corporate experience in online marketing to equal use.

Three years later, Cakes and Kids sales are doubling annually and Degnan is in charge of her own destiny. “I’m not going to say it was an easy choice to quit my last job because I gave up a large salary,” she says. “But now I have things up and running its a no-brainer: I can be CEO of my own company and be home for my kids at the same time.”

Mamma’s Got a Brand-new Brand

Motherhood and a pink slip were also the inspiration and impetus for Kate Castle’s start-up, launched in Winchester, England. The mum of two had her bright idea—the BoginaBag portable toilet—when her kids needed to visit the distant loo at a campsite in the dead of night. Then she too was made redundant, having moved to part-time hours while she raised her family.

“They were forcing me to go full time or leave. A lot of women and mums are pushed into that position and it’s a real shame,” she says. “There’s only a short amount of time before your children start school and it becomes easier for you to put more hours in, but it’s nice to have the opportunity to be around for them when they’re younger.”

With the BoginaBag selling well online and through camping stores around the UK, Castle is not finding her working life to be any easier, but at least she has some control over her schedule. “I work more now but the hours are far more flexible around what my kids need. I might work in the evenings but it means I can go to sports day or the school play.”

As ‘mumpreneurs’ both Degnan and Castle had to fight to be taken seriously. “I ran across some attitude: ‘Oh that’s a nice little hobby you’ve got’,” says Degnan. “It was when I quit my job people’s eyes really opened and they went: ‘Wow, she must be selling quite a bit’. There’s a lot more respect as it has grown—people acknowledge that you really have a business.”

“You have more to prove,” agrees Castle. “A lot of men in business are used to working a very structured, full time, nine-to-six job. They find it difficult to understand that you can take something incredibly seriously while not necessarily being committed to those hours.”

High-flying Ambitions

As a young, single woman making her way in two male dominated industries, Abingdon Welch encountered different challenges. After qualifying as a pilot (where women make up just 7% of the numbers) she decided to launch her own line of aviator watches, frustrated by the dearth of designs available for women.

Stumping up $60,000 of her own money to start The Abingdon Co., Welch bucked the stereotype of women being conservative in business. “I can’t say I’m risk averse because I’m a pilot and over the last six years I’ve sent hundreds of thousands of dollars overseas, but it’s calculated risk,” she says.

Her advice to new women entrepreneurs: “Step out of the comfort zone: it can’t get bigger unless you do.” Just control the risks you take by researching suppliers thoroughly. “Ask for referrals and recommendations. If they are a decent company with solidity and history behind them they’ll be happy to provide them.”

Welch’s relationship with the factory that produces her timepieces has grown beyond her expectations. “These guys are my family now. My supplier from Hong Kong has made my dreams come true and I treat him like another father,” she says. Only Welch, who itches to get up in the air every day, has never had to board a commercial flight to visit her new ‘relative.’

“All of my products have been sourced online,” she says, including a new jewelry line that the Oregon-based entrepreneur is working on with a New York manufacturer she found on Alibaba.com. “I wouldn’t be here without online sourcing.” Next on the sourcing agenda: an Abindgon-branded line of travel goods.

It’s the same story for Degnan, who expanded her business beyond handmade fondant creations by reselling party supplies sourced through shopping website AliExpress. “If I had had to get on a plane and fly to China to find those products—as a woman on my own I would never do it,” she says. “But I can hop on the computer, converse very effectively with people thousands of miles away and get the products shipped right to my door.”

Castle had visited Chinese suppliers with her previous employer, the U.K.’s leading hardware retailer, and would have had few qualms about going back. “As a culture they have a lot of respect for females in business and I’ve dealt with quite a few women within China,” she says. Her problem was more practical: “I didn’t have the budget to travel for myself like when I was working for a big company.”

Online sourcing ensured BoginaBag made the transition from great idea into finished product. “If I’d had the idea five years earlier I would have struggled to produce it,” says Castle. “The U.K. is no longer making those kinds of products yet there wasn’t the set up for people sitting in their kitchens to be able to contact the factories.” Online sourcing “has enabled all kinds of people to make connections with suppliers who can make products for them,” she says.

Sources of Inspiration

As well as sourcing and selling online, women in e-commerce are replacing the old-boys network that used to drive business relationships with new girl-powered forums. While a lack of female mentors is a problem in the corporate sphere, women entrepreneurs are forming strong support networks online.

Degnan has built a virtual network that includes party planners and other fondant sellers who could easily be classed as competitors. “I’ll send some of these folks items for photo shoots and they’ll give me recognition on their blogs,” she says. “It’s partly about getting my name out there but partly about having connections with women who do something similar to me. If I have new product ideas I bounce them off these women and get feedback.”

Castle has a dragon for a mentor, having enticed a prominent U.K. businessman to invest in BoginaBag when she appeared on reality TV show Dragon’s Den—ironically turning down offers from the two female “dragons” on the show. Castle passes on her own experiences at entrepreneur workshops, where two thirds of the participants are women.

Welch is keenest of all to mentor the next generation, setting up the “It’s About Time” scholarship, which flies one girl each year to the Women In Aviation Conference to inspire them to follow a career in science, technology or aeronautics.

“We don’t do it for the publicity—if we did I would be doing a poor job as there have not been a lot of stories about it,” says Welch. “When I was 14 my life changed as a result of hearing a couple of pilots talk on career day. I want to make that opportunity available to other women.”

Whether in the cockpit or at the keyboard, shooting for the sky certainly sounds more fun than just holding it up.