The comments brought an angry reaction from GPs, who said the health secretary should not make 'sweeping statements' unless she had proof and would act on it.
Ms Hewitt said last week: 'Some women patients in some Muslim communities are feeling they can't trust their own GP who is from the same community and knows their extended family.'
'If they go for particular situations, such as a sexual health problem or domestic violence, they fear they will share that information with other members of the family or community.'
Asked whether breaches had actually occurred, Ms Hewitt said: 'It is happening, but the women are too afraid to complain.'
Ms Hewitt's comments were made at the Fabian Society in London last week after she made a speech about the future of the NHS.
GPC deputy chairman Dr Laurence Buckman said: 'If there has been a breach of confidentiality, the health secretary should go to the GMC.
'The vagueness of her comments make them even worse — she is putting all Muslim GPs under the spotlight unfairly.'
Chairman of the Muslim Council of Britain's health committee Dr Abdullahi Shehu said: 'All doctors in this country, Muslim or not, have to abide by GMC guidelines. Any breach should be investigated, but reluctance to talk about sensitive issues with members of your own community is human nature; it's not purely applicable to Muslims.'
In the past 12 months, 11 doctors have been referred to fitness-to-practise panels over allegations of intentional disclosure of patient information, according to the GMC. The GMC was unable to say how many of the doctors concerned were GPs, or whether any were Muslim.
GMC policy adviser Michael Keegan said that patients in some close-knit communities have 'added concerns about the confidentiality of their personal information'.
The DoH denied Ms Hewitt had accused Muslim GPs of breaching confidentiality. A spokesman said she had 'recounted evidence from the Muslim Women's Network on Health' that Muslim women were not visiting their GP in some areas 'because they are nervous about reporting certain problems'.