Forget the old adage about staying away from religion and politics, if you want to get an emotional conversation going raise the question of when is the best time to have kids?

Because despite the cliche that really, there is no “perfect” time to have a baby,  the crass question of  whether it’s “better” to be an older or younger mom is an emotional one regularly debated in blogs, papers and talk shows.

The  overarching trend is that women are having kids later, a shift that is impacting  fertility,  family dynamics and celebrity culture .

Leaving aside the health and financial issues for the moment, from the perspective of post-baby career success, is there any specific advantage to being an older or younger mother?

One common view is that being more senior and established professionally should make post baby success easier.  Certainly, the unspoken convention in professional services industries like law and management consulting used to be that if a women was serious about her career, she didn’t have a baby until she reached partner track.  This “pre-mommy” mentality extends beyond these professions to describe younger women deliberately working much harder than their male peers in an effort to establish themselves and “bank” career points – before they go on maternity leave.

When I was in law school, there were several “mature students” in my year.  Looking back, these women were probably in their early 40′s at the most.  And they had kids, who were around 10 and 11.  At the time, in my early 20′s, blissfully naive and convinced I had it all figured out, I thought this seemed backwards.  Since becoming a parent, I’ve always wondered about those women – my guess, is that after some initial hiring hurdles, they are all enjoying interesting and successful legal careers.

So if you want to have a close family and successful career – should you have the kids early or later when you’re more established?   Career advice blogger, Penelope Trunk,  puts it this way: you have your whole life to get a career, but that it not true for a baby.  However, a stable relationship, a means of financial support, all of these tend to be tough when you are young and having a baby without them, is of course possible, but probably not the best decision.

Sylvia Ann Hewitt‘s research suggests that regardless of when a woman becomes a mother,  just by becoming one, she’ll face a career setback and if she steps away or “ramps down”  then for the rest of her professional life she’ll face an enormous fine in terms of both cash and career arc, punishment for going outside of what she calls “the male career competitive model” which is built on a bedrock of unbroken service.   For her, change will come through demographics.  Specifically, falling birthrates combined with huge numbers of retiring baby-boomers will lead to what Hewlett calls “shortfalls in the talent pipeline”.

The MomShift interviews, are of course, focused on positive success stories and what I’ve found, is that:  post-baby success can happen just as easily with older as with younger Moms and that very few of my 135 post-baby success stories actually planned their babies around their careers or the other way around.

Women who waited until they were more senior and established, said that it gave them greater control over their schedule, a proven track-record and an established professional brand.  They also frequently referenced the belief that having kids later allowed to have a better sense of who they were and what post-baby success meant to them.

MomShifters who had their kids younger described the advantage of babies during their twentysomething wilderness years, “getting it out of the way” so to speak as they were finding what it is they wanted to really do professionally. For some this meant babies while they were in professional or graduate school or as they were testing out different careers. For others they took time to be home, then got back in to workforce and were still only in their late twenties. Several have spoke about the advantage of having children who were older and more independent as they were reaching the age and career stage that put them in the running for more senior roles.  For several interviewees, their children were what inspired them to achieve more professionally whether this meant increasing their finances, finding work with more meaning  or returning to school or training to be able to achieve more professionally.

The lesson that I’ve taken from these stories is that there is no right answer and that most women do have many more options than they realize.  Careers, like families are very personal and individual, and decisions on when or how, can’t be prescribed by career counselors, media commentators or colleagues.