Jade has a post up over at LabSpaces about why she isn't a parent and views a career and being a mom as mutually exclusive activities. It's a personal and subduedly emotional post that I would bet a lot of people can identify with. On the other side of the coin, you can also find posts on being a scimom by Dr. O, Janet and Gerty-Z, as well as other links within those referencing the #scimom hashtag started at It's Not a Lecture.
In Jade's post she indicates that it was growing up in her household and watching her mother deal with the stresses of parenting is what convinced her that motherhood was not for her. Unlike the Jade's commenter who goes all self-righteous about parenting, I don't think the kinds of things you have to do to be happy as a parent with a career is something that everyone needs, in order to fulfill their lives. The guild of parenting is not unlike that of academia, where the default assumption is that if you do not conform to the in-group measure of "success" then you have certainly failed.
Balancing careers with kids while maintaining a good relationship with your partner is way harder than you might think before plunging in. It's easy to get selfish about accomplishing your own goals and we all fall into that trap at times, putting huge strains on our relationships. No one can be everything to everyone at all times, we all make small sacrifice everyday in some aspects of our lives. The key is to rotate those sacrifices so that you can give more to what is most critical on a given day. Some days you need to get things done at work that can not wait. Some days you'll need to miss a deadline to be with your sick kid or help out your partner or just to spend time with both because it's important. As a result, you're gonna miss somethings at work or at home that you really don't want to, but that's the game. The perfect parent who can do everything rides a unicorn to work and never has to sit through a meeting that wastes their time (The latter being the more rare of the two).
But why is this the pinnacle of success? Whereas I agree that no one should ever feel like they can't have kids for career reasons, there are plenty of people who actually don't *want* to have children just like there are a ton of people who don't actually want a tt position (shhhhh). The default opinion expressed by Jade's commenter yannisguerra is the same bullshit that PIs so often spew onto their trainees, but sometimes not wanting something is a feature, not a bug.
I forget who said this or where the conversation happened, but a recent parent mentioned that they were never so avidly pro-choice until they had a child. Wise words.