Access to family planning. The ability to hire a nanny. Enough money for a second car. These are all things that are pretty much necessary for a woman to become fully liberated and able to work and live as she pleases - and they are also things that are only within reach of middle and upper class women.
While all women have access to condoms - though some may be more subject to shame than others when they go to buy them - the ability to get birth control, Plan B, and abortion if necessary means a woman is completely free from forced pregnancy. She can get an education and work without having to drop out or quit because she's knocked up. However, reproductive healthcare is a class privilege. Not all women can afford birth control - if their condoms break, they're SOL. Some women live in religious areas where few pharmacists are willing to dispense birth control, and getting their pills can be next to impossible unless they have the time and means to travel to the pharmacies that will give it to her. Same goes for Plan B. Some women live in places where there is no "local" clinic, and getting an abortion means taking a few days off work - which may take a chunk out of her paycheck that she can't afford to lose - and traveling across the state, or to another state entirely, which may be too costly, not to mention she needs to find someone to take care of the kids if she's already given birth. Some women may live near clinics but still can't afford the procedure.
If a woman wants to full-time, she has a few options: she can have no kids, or she can have kids and take them to daycare or hire a babysitter. Women with school-aged children and who don't require sitters during the day are still held back by always being the one to leave work and stay home with the kids when they're sick, and they're usually the ones who are expected to be home when the kids come home, or face the judgment women face when they leave the children to "fend for themselves" after school. Of course, this is more of a worry in neighborhoods of low income than in suburban neighborhoods.
Ironically enough, single mothers and lower class women had been doing this juggling act long before second wave feminists began their struggle for work equity. They had to, they needed the income to either support their families or support themselves - which was rare, since before second wave feminism women lived with their parents until they got married, but there were circumstances that led to women living on their own - out-of-wedlock pregnancy, divorce, widowhood, loss of parents, etc. These women typically held "feminine" jobs; they were waitresses, nannies, seamstresses, maids, and in worst-case scenarios, prostitutes - and in such jobs there is no need to demand equality with one's male coworkers because they simply didn't exist. There is a need for adequate pay and working conditions, and an inherent level of oppression in such jobs, and despite workers' movements, such problems still have not seen resolution.
When a woman has to work the "second shift," or the domestic workload waiting for a woman when she gets home from work, she is robbed of energy and less able to perform in full force at work. The other option is to hire domestic help, which is only an option for upper class women. When the cooking, cleaning, and childcare is solely a woman's job, her job prospects are limited and she only has so much energy for when she does work, meaning she's less likely to be promoted or given a raise than her male coworkers, who for the most part have fewer responsibilities outside work and have more time and energy to put into their work performance.
Not to mention, technological innovations that have made housework easier, and thus have freed up time and energy for women, are in themselves only accessible by those with enough money. Housework is easier for women in the upper and middle classes than those in with lower socioeconomic statuses.
Notice how in all this, the work of men is largely absent. They don't need to worry about an unplanned pregnancy getting in their way, only the threat of having to pay child support or a nagging "baby mama" demanding he be more involved. A man doesn't have to worry about taking care of the kids, or working the second shift, that's all "women's work." If women can expect liberation and equality, their oppressors - men - need to give up some of their power and take up some of the burden that weighs women down. This may in turn make men somewhat less liberated, but at least it will level the playing field.
Full liberation achieved alongside gender equality requires that childcare and reproductive healthcare be available to all people, regardless of socioeconomic status, so that no person ends up shackled to an unplanned pregnancy, to a person they did not intend to marry but did so out of obligation and responsibility, and no one is kept from a job because they cannot get anyone else to take care of their children. Finally, these childcare professionals, along with seamstresses and anyone else who takes up outsourced women's work, must be paid well and treated with dignity.