A recent study carried out by researchers in Warwick, UK and Georgia, USA (reported here in the Telegraph) has found that in areas where men are perceived to have a natural advantage, such as in carrying out spatial tasks like parking and map-reading, lack of confidence will make women worse at those tasks. Basically, if you tell women they are rubbish at parking, they will be.
I would actually take this one stage further. I think that if you tell women that they are rubbish at parking, not only are you making it a self-fulfilling prophecy, but you are also inextricably linking incompetence in spatial tasks with femininity. This means that not only are you making it more likely that they won't be very good at parking their cars, but also you are saying that if they are good at parking their cars they are not proper women!
On several occasions when out driving lorries, women have said to me, "Oh, I couldn't drive that thing, I've got no spatial awareness". What they are really saying to me is, "I couldn't drive that thing, I'm a proper woman." The fact is, if I asked those women if they could organise their cupboards so that they can see and reach all the things they want to see they would say yes. If I observed them in a supermarket manoeuvring their shopping trolley round several stationary trolleys so that they could get to the deli counter in front of the woman with the 3 screaming children in tow without it looking like they were racing, I'm sure I would be impressed with those same spatial skills that they claim not to have. These examples may sound horribly stereotypical but it is in stereotypes that we are dealing when talking about women drivers. The fact is, women carry out complex spatial tasks all day every day. There is just something about driving that we are told is man's work.
Having said that, it is precisely because of the association of driving with men that makes it such a good area to work in when trying to challenge these stereotypes. Every time somebody of either sex sees me or any other woman successfully manoeuvre an articulated lorry into position it's just another little nail in the coffin of these outmoded ideas.