If you already thought women were competitive, just wait until you have children.
The comparisons begin almost from the moment of conception and as for the birth, if you don't manage to push it out at home using just deep breaths and determination, you can be made to feel a bit of a failure – as if it matters as long as your baby is healthy and you survive.
But all of that pales into insignificance when the real choices about bringing up baby begin. That's when the mummy tribes start to form: the breast vs bottle-feeders; the pureeing disciples vs the baby-led weaners; the cloth vs disposable nappy users; even the co-sleepers vs the get-baby-in-its-own-room-as-fast-as-possible brigade.
Later on, when baby is old enough for mum to think about a possible return to the workplace, those who go back to paid work can feel in a different universe to those who don't, and vice versa. Friends who stay at home full-time say it's mainly other women who look down on them and assume they have taken the "easy option". Others who work resent the term "full-time mum" and its implication that doing paid work means you are any less "full-time" than any other mother.
In truth, I think a lot of what feels like competitiveness comes from actually being quite unsure about what we are doing.
Even though every human being in the world has had a mother at some point in their lives, being a mum can often feel like a minority occupation. In the absence of parents or extended family nearby, the day-to-day business of looking after children has become a solitary activity. So many of us are muddling through, doing the best we can with very little experience and without the practical expertise of older women to draw on.
Add to that the importance our society places on paid work and the perceived loss of status that comes from leaving the workplace, however briefly, then the ridiculous pressure to achieve the right balance between work and home life and it's no wonder mothers find themselves clinging to one or other ideology of mothering as though their lives depend on it. The hundreds of books that play on parents' insecurities don't help.
The fact is, there is no such thing as the perfect choice for a child and there is no such thing as the perfect mother – a truth recognised by the psychoanalyst Donald Winnicott, who said all mothers could or should ever expect of themselves was to be "good enough".
If we are honest, none of us really knows what we are doing. But we do want the best for our children. And that's the important thing – to do the best we can and to respect each others' choices. And be glad that the lucky ones amongst us have the choices that we do (just watch Meryl Streep in the 1979 film Kramer vs. Kramer for a reminder of how things used to be).
So on Mother's Day this Sunday I pledge to try not to be judgemental about what other mothers do and to raise a glass to all of us for the simple miracle of making it through another day.