Madelyn Murray O'Hair comes to mind. For years she was THE Atheist.

Annie Laurie Gaylor, and her mother Ann Gaylor. They started The Freedom From Religion Foundation many years ago. You can read about many more in the book that Annie Laurie wrote. "Women without superstition". [amazon.com]

I'm glad to say i have not encountered Harris and i avoid Dawkins like the plague. Most rational atheists are part of the humanist movement and work to promote equality as opposed to hysterical posturing. ?

Many of the prominent atheist figures have become so by debating. And debates are festivals of posture and rhetoric tricks. Hitchens was very good at this, but when women argue the same way they are seen in a very negative way by society. The are seen as bossy or mannish. I think this double standard and the social pressure of women not to raise their opinions lest they be shrugged of as hysterical is a good reason for there being less women.
The stigma of coming out as atheist might also be bigger, I guess.
(I talking about general trends here and not specific cases, just to be clear)

Several studies have shown that women are much more likely to be serious about religion. Kinda a Homer/Marge dynamic. This most likely has something to do with the common declaration that you are bad if you don't go to church and more so if you don't take your children. This might also have something to do with the fact that women have more of a battle in society than men and adding the taboo of godlessness is more than they want to bear.

That said there are many women who are both atheists and vocal about it.

Here are some to look up:
Polly Toynbee
Greta Christina
Ophelia Benson
Susan Blackmore
Sumitra Padmanabhan
Susan Jacoby
Jennifer Michael Hecht
Patricia Churchland

Granted none of these ladies are one of the “Four Horsemen” of the New Atheist movement but all are accomplished, educated and have a public voice.

Hope this is helpful.

You’re not looking hard enough [msmagazine.com]

I suspect that there are a great many female atheists who, if they chose to be, could be every bit as prominent in the public sphere as Harris, Dawkins, Hitchens et al. However, it's my experience that women generally tend to be more content to keep their beliefs (or lack thereof) to themselves, rather than feeling the need to go around telling everyone else what their thoughts are on whichever their favourite subject happens to be, like men often do.

Look where Madeline Murry O Hare ended up. She was one of the most hated women in America. Not a fate many of us would relish.

There seems to be a loud anti feminist part of the atheism movement. I don't know what percentage but they seems to be tolerated by the larger community. I know this has caused a number of women to step back. Check out elevator gate for a good example. tl;dr a women request men not to approach her in a way that made her nervous and the male atheist community freaked.

There are several on The Atheist Experience and many more on Godless Bitches

I think that the issue of atheism is distorted in the Anglo-sphere. In other western countries atheim is so entrenched that there is no real need for advocacy. Though this can change dramatically very quickly.

But to an extent the absence of female atheist voices could play in the hands of conservatives who might want to criminalise abortion.

Australia might be slipping down that chute. Apparently the new despot from down under seems to feel that some god sent him on a mission.

One can only hope that liberal female voices are being heard and listened too when it comes to issues such as abortion and contraception etc.

Annie Laura Gaylor (co-president of FFRF), Barbara G. Walker (https://www.goodreads.com/book/show/25834982-belief-and-unbelief and many other 'pagan books', Jennifer Bardi Editor of the Humanist. Also, a recent Humanist magazine had 5 active Black females [thehumanist.com]. There lots of active women in this area.

I have an "evolve" fish on the back window of my truck and magically a dent appeared where it could not have appeared by accident. This is what happens when we are not careful.
It might be easier if we are relatively ananomous but unless there is a support system it's dangerous in some places (I live in South Carolina). I always like Betty Bowers but she is more entertaining than activist.

Give it time! Women are putting words to action every day but unfortunately are overlooked or just aren't recognized. But one day (hopefully day one and not just one day) Female atheist activists will be known for the their work and start popping up like daisies

I am a woman and a feminist but not an activist active how I don't see the point in trying to convert anyone they will when they are ready and if they never get there it would still have been a life worth living I can't quite see what would be gained - people I meet are kindly enough - what does it matter if they have a sky god or not ? Isnt that a personal thing like a child having an invisible friend would you rip it off them ?

Since age 18, I have been an environmental activist, peace demonstrator and Democrat activist.

I care about the welfare of people- their health, education, housing, school, jobs, civil rights, and civil liberties. I care about protecting the environment.

Although I live in a rural, conservative, Christian town, I don't feel attacked. I have been an atheist since age 13.

My friends love me for who I am. Likewise. Two are ministers. They never hassle me for being an atheist.

for me its because its a waste of my time -i have no god i have never ever had one so what would there be for me to be active about?I have no complaints about people who believe its their business not mine

Women take the fight against the religious patriarchy- which crosses all cultures. Our activism is just that-from school boards, city councils, and day to day issues. We may hold our spiritual practices, beliefs and rituals very different than the patriarchy does. We just get it done in silence but wear the hat...and let the patriarchy who they are dealing with

I see no reason for activism in atheism.

Not for my non-belief. But for other causes,(e.g. first amendment). I would stand with others for separation of church and state. As for female atheists activist, I live in Kansas, so things are pretty futile. I also got threatened to be beat-up after I revealed to a group of people I did not know well that I was an atheist. I practice what I preach about not imposing my thoughts on religion, (or lack thereof), on others. The best I can do is be a kind person, and later share to those I trust that I am an atheist, and that might change their attitude.

Although she has backed off on the classification, Kyrsten Sinema who is now running for senator in Arizona initially acknowledged that she was non-theist. She is also bi-sexual and has a good chance of winning in November, at least I hope so. Also I didn't notice anybody mentioning Susan Jacoby who has written some excellent books on the movement. One of my favorites is Lisa Randall who is a physicist and an excellent author. Of course there was Madalyn Murray O'Hair and nobody took it more seriously or was more in your face than her but she is not living so not current.

I found this site with a list of the 'top' (what ever that means) Atheists in the world.
You'll notice that many of them are women.

To add to other suggestions...

In the professional world
• Francesca Stavrakopoulou [en.wikipedia.org]
• Eugenie C. Scott [en.wikipedia.org]
• Marlene Winell [marlenewinell.net]

In the broader social world
• Greta Christina [en.wikipedia.org]
• Sarah Haider [en.wikipedia.org]
• Rebecca Watson [skepchick.org]
• Shannon Q

It's safe to say there are women out there who are trying.

Not sure if she is Atheist or Agnostic, but Karen Garst wrote a great book called "Women v Religion" I rather enjoyed.

[faithlessfeminist.com]