Today, just 3.5 per cent of practices in England are all-women.
But with women outnumbering men at every stage of professional selection - they make up 59 per cent of this year's registrar intake and of last year's new RCGP members - it's the face of the future.
This ‘feminisation of medicine', said West Lothian GP Dr Brian McKinstry, is bad for medicine and bad for general practice. Writing in the British Medical Journal, he recently subjected women GPs to a drubbing.
More often than men, women GPs work part-time, have babies, take career breaks and then retire early. They give a relatively poor return on the state's investment in their education.
With Mill Hill's two full-timers (Dr Kate Cabot and Dr Imogen Measday) on eight sessions a week and two part-timers (Dr Jennifer Durandt on six sessions and Dr Anne Scully on four), he has a point.
But this full-time/part-time balance is no different to any other mixed-gender practice. The current four-woman partnership has accommodated two maternity leaves but not a sabbatical and no-one is planning early retirement.
As for a poor return on investment, Dr Durandt, 49, who has a mature capacity for moral outrage, qualified in South Africa. ‘A lot of doctors' training is paid in the third world and they are then poached by this country.'
The Mill Hill team has been all-women since Kate Cabot joined as a registrar in 1989. In 2001, they briefly appointed a male partner but he was unable to join due the delays in qualification. Since then, they've had just one male registrar.
Dr Cabot: ‘It's not because men are not welcome. It's just the way it turned out.'
Dr McKinstry has suggested that women GPs are inefficient. They refer more patients to secondary care and they are long consulters.
Dr Cabot conceded that her practice are relatively high referrers, but no higher than other local practices in an area with a high level of ethnic and social mix. ‘Each of us has a slightly different style of referral,' she pointed out.
As for consulting longer, this too is individual. ‘It's never caused any problems and we always see all the patients by the end of the morning. So I can't see why that matters.
In her mixed training practice, Dr Durandt pointed out, the longest consultant was a man.
But women do not play a full role in medical life, do they? A study of GPs in Scotland has shown their contribution is 60 per cent of men's to education, research and teaching. They are disinclined to engage in medical politics.
Yes, women are underrepresented on political organisations. ‘Some women don't choose to go and sit on committees, particularly if evening meetings are involved,' Dr Cabot admitted. With a home, husband and a 14-year-old daughter to juggle with her full-time work, she ‘wouldn't feel happy going out for more than one evening meeting every couple of weeks'.
All the partners attend ‘relevant and topical' meetings and working groups; they make a point of voting for the women candidates. Dr Measday sat on the board of her practice commissioning group.
‘But it was a huge work commitment outside practice and also impinged on practice work. It all got a bit too much.' After two years she resigned.
As for teaching and education, the Mill Hill team all teach undergraduates and Dr Cabot is a GP trainer. Their daytime non-clinical commitments are as heavy as any man's.
A feminised profession has other, less tangible aspects. Two years ago Dame Carol Black, then president of the Royal College of Physicians and now National Director for Health and Work, scandalised medics by saying that with too many women entering medicine, a feminised workforce would lose status. Dr Durandt agreed: ‘The world is still very sexist so if general practice became the women's option we'd lose status in the eyes of others.' But they would not do their jobs any less professionally.
Self-evidently, there are limitations to what a single-sex practice can offer - like patient choice on GP gender.
‘We are very happy to refer to excellent male colleagues down the road,' says Dr Cabot.
Sited on the borders of a high-crime, high-rise estate, are these women more vulnerable to violence?
On the contrary. Just as women are less likely to be assaulted in the street, so they are well protected against in-surgery violence. They have never had to press their panic buttons or close the surgery off.
Dr Imogen Measday: ‘We are aware of potentially difficult situations and calm things down to avoid them escalating.'
Of course female GPs have their strengths. They are patient centred. A ‘good symbol' for the Mill Hill partners is that when they see non-English speakers, they insist on face-to-face double appointments with interpreters.
And using a phone call list, they make themselves available to patients who do not want an appointment but have a question, but there is a cost to this.
Dr Cabot: ‘We have to rein ourselves in constantly because we are going too far. Patients ask us for letters for their freedom passes or housing and we find it difficult to charge. Every few months we slip back into being kind to the detriment of other patients and ourselves.'
Women are also emotionally focused.
Dr Cabot: ‘We see a lot of patients with psychological and psychiatric problems who we stick with and don't refer. But there are some extremely adept emotional consulters among male GPs.'
In short, the Mill Hill team do not believe the service they offer patients is essentially different from any mixed practice. Where they are different is in achieving a better personal work: life balance.
After all, juggling commitments is what women are good at.
Dr Cabot said: ‘Even if you're full-time you have at least two patches in the week when you can get on with other things, reflect and be normal. You need this to cope with the mental stress of dealing with patients all the time.'
Flexibility is easier to achieve when you are a partner rather than salaried. Dr Cabot would encourage more women to choose the partner route.
And flexibility, along with autonomy, are essential ingredients of professionalism, she pointed out.
If the profession loses that autonomy ‘you're talking about automatic doctors that just do their bit and go home.'
And no one wants that.
Do you work in all-men or all-women practice? We would be keen to hear what the benefits and disadvantages are. Leave your comment below or email GPLetters@haymarket.com.