WANT to know the single worst career decision a woman can make?
Having a baby.
Want to know one of the best for a bloke's resume?
Welcome to the parenting paradox.
This year I've watched several of my girlfriends return to work after a stint of maternity leave at home with their first baby.
Each has re-entered the paid workforce excited by the prospect of adult conversation, intellectual stimulation and being able to drink a cup of tea while it's still hot. Wearing freshly dry-cleaned suits and new shoes, my mates began the working year full of expectation and energy.
Two months in and everyone is bitterly disappointed.
Yes, there's the inevitable difficulties faced by new parents trying to maintain work and caring responsibilities for the first time. Paying for childcare is a nightmare and that's only if you've cleared the hurdle of actually getting to the top of a waiting list. The double and triple shifts of a day at the office, dinner, baths, bedtime routines and wakeful nights are exhausting.
But that's not what has left my working mother friends feeling so dejected. What's hurting them is the motherhood penalty. One has returned to the same job but with substantially less interesting work. Her leadership role in the workplace has disappeared and so has her confidence.
Another is working - and being paid - three days a week but her workload remains the same as when she was employed full time.
A third has been overlooked for travel opportunities that rightfully should have been hers.
Another was told she isn't thinking clearly during what is 'an emotional time' and stripped of responsibility.
There is an unspoken assumption that you're a less valuable, less effective and less committed employee if you're a mother of young children.
And that same assumption most certainly did not apply to their new-father partners.
For men, the opposite is true.
The motherhood penalty has been proven again and again but more recently researchers have also noted a fatherhood bump.
That is, when a woman becomes a mother it holds her career back. It automatically renders her a less valuable employee in the eyes of those who work with her. However when a man becomes a father this new-found responsibility actually works in his favour at the office.
Shelley Correll, Professor of Sociology at Cornell University, sent out hundreds of fake CVs to prospective employers.
The CVs were identical except for two things. First, half of them had a man's name and half of them a woman's.
Second, half the CVs - both the men and the women's - included a line that implied they were a parent. That line was something like being the coach of an under 10s soccer team or a member of the P and C.
The results were staggering. Women with children were 50 per cent less likely to get a response from an employer. Men with children were slightly more likely than any other applicant to get a call back for interview.
When Correll reproduced a similar experiment in laboratory settings, mothers were offered salaries of around $11,000 less than women without children. Fathers were offered salaries of around $2000 more.
So what does that tell us? Well, when a woman has a baby it is assumed she will be less reliable, less committed and less effective as an employee. When a man has a baby it is assumed he is more responsible, more stable and more dependable at work.
It's been almost two years since I had my first child and rendered myself instantly less employable.
While becoming a parent is - without comparison - the best thing I have ever done, I am well aware of the negative impact it's had on my career. How women are perceived and how they are treated at works changes substantially after having children. And it isn't for the better.
To some extent there is logic in that. I am a different kind of employee to what I was two years ago and so are my new-mother girlfriends.
Becoming a parent changes you and it changes your priorities. Particularly when a child is young and most dependent on you. While I am just as able and talented as I was two years ago, I am no longer content to put in 16 hour days and I can't always stay late for a networking function.
But here's the thing: The same is true for my husband.
The prejudice of employers against mothers and in favour of fathers is based on the most outdated of assumptions.
It flows from an expectation that women are mothers first and people second and that men are providers first and fathers second. Neither is true.
There have been some enormous structural improvements in easing the transition of women in and out of the workforce around childbirth. There are more still to come.
More important though, is the cultural shift that acknowledges working mothers as committed and capable employees just like everyone else. And equally, sees fathers a contributors to their children's wellbeing in ways that extend far beyond the financial.
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