Assuming there isn't a secret world where stay-at-home mothers get to loll about all day in spas sipping Pinot Grigio, there must be some reason why more women than men stay at home with children?
Of course there are lots of reasons; women are hardwired as caregivers, women are refused flexibility and resign, women are put on the mummy-track, women earn less than men, women grow up in a society that sees more mothers at home than fathers - and many more reasons - take your pick.
I wonder too if the fact that women take maternity leave and men don't is a factor? Is maternity leave a taster of stay-at-home life, and does it ease us into the idea that we could potentially do it full-time?
In my early thirties, I went to the office every day, just like my husband. We worked similar hours in similar jobs, and travelled home together, talking about work stuff and what we'd do that weekend and who was thinking of buying an apartment in Bulgaria (it was the early noughties). I earned as much as he did, and spent it on shoes and makeup and cocktails and holidays (again, it was the noughties).
The arrival of a baby-bump didn't change much in terms of work and money and day-to-day living, so - except for the cocktails - life went on pretty much as it always had done. Then my waters broke - in my office - and nothing was ever the same again.
Well, of course it wasn't the same - we had a beautiful little daughter, who completely took over our world from the moment she entered it. But day to day life changed utterly for me. And it did for my husband too, but not to the same extent. He still went to work every day - he just had nobody to chat to on the commute. I on the other hand swapped heels for flats, and coffee for decaf tea (at least until I saw sense).
Work colleagues were replaced by a tiny girl who was my boss, my co-worker and my team all rolled into one. Instead of conference calls, I had fleeting attempts to reply to text messages while she sat in her chair for oh, at least five or six minutes before wanting to be up in my arms. Lunch from the deli was replaced by a thrown together sandwich at the kitchen counter, with a baby on the hip. The afternoon team meeting became coffee with friends or a less exciting trip to the supermarket. And home-time was not about my commute anymore but all about my husband's - how soon could he get home to take our daughter, so I could take a deep breath.
Our relationship changed too. My husband used to come home and tell me about something that happened at work - I'd reply with a story about something that had happened at home - something very interesting like how long the baby had slept or something funny the postman had said (who was after all, the only other adult I'd spoken to that day). My husband never once asked how I hadn't found time to cook or why the laundry was taking on Everest-like proportions on the dining room table, but I'm sure it must have crossed his mind to wonder what on earth I was doing all day. Actually, I still don't know what I was doing; I just know it took all day.
Two months in, I had figured out the baby stuff, I'd found a routine, and I'd even cooked dinners on two particularly great days. The realisation dawned: I was a housewife.
The me who had lived a life similar in every way to that of my husband, could never have imagined being a housewife; working on dishes and laundry instead of spreadsheets and e-mails. And it wasn't an overnight transformation - it was gradual, with the significant distraction of a delicious baby girl. But yes, I was a housewife.
And back at work now after a third maternity leave; if I imagine a situation where I'm not working, I know I can do it. For my husband, it would be a much bigger adjustment. One that he would embrace, but the psychological leap to house-parent would be far greater for him than for me. Which is why, all other things being equal, if one of us had to give up work for a period, I think it would be me, and I think it's partly because I've been there for a test run and I know I can do it.
It's one common factor for most mothers - we have maternity leave, and our partners don't. So maybe that's part of the reason more mothers stay at home. Or maybe it's all the other stuff - society and salary and employer inflexibility and guilt. Or maybe it's just the innate desire to be there when they're small - something that stems from carefully carrying them inside us for nine months before they see the world.
Either way, I've had a taster, and if it came to it, I think I'd be just fine with second helpings.