First survey form 2010 by the now disbanded Women’s National Commission which included 650 UK women’s sector orgs.
web.archive.org/web/2011081809…
It found that 99% (of the 297 women-only service users and providers asked) value women-only services:
equalityhumanrights.com/sites/default/…
Very similar findings: 95% of users said the women-only aspect of the service was important.