International Women's Day provides an opportunity for us to celebrate women's contribution to society and focus on the challenges we still face. Despite much progress here in Britain and worldwide on the status of women, sadly we still face many disadvantages.

We receive lower pay than men for equivalent work. We are more likely than men to be victims of domestic violence. Discrimination, abuse and violence are problems for women worldwide, regardless of sexual orientation, but for the roughly 210million lesbians and bisexual women worldwide the challenges can be all the more acute.

Every day, lesbians and bisexual women become victims of forced marriage, forced impregnation, honour killings and other violent attempts to either change their sexual orientation or punish them for it. Many feel unable to seek justice, fearing that in doing so they may disclose their sexual orientation, putting themselves at risk of reprisals or even prosecution.

Governments around the world rightly seek to address wider gender inequality and discrimination, but often their efforts to tackle inequality fail to materially address the specific needs of lesbians and bisexual women. There are, for example, many vital development programmes working to ensure that girls worldwide can access and complete education.

But for lesbians and bisexual girls in countries where pupils can be legitimately excluded from school simply because of their sexual orientation, these programmes may have limited benefit. And efforts to tackle the poverty of women and girls worldwide by helping them to achieve and maintain employment and financial independence are undermined in the many countries where women can be denied employment or sacked simply because they are lesbian or bisexual.

At Stonewall we know that the fight for equality for lesbians and bisexual women worldwide will only be effective if it is an integral part of the wider movement to achieve full equality for women and girls. But for this to be the case those working towards gender equality worldwide - including development agencies, development NGOs and international institutions - must understand and respond to the specific needs and threats to lesbians and bisexual women and girls.

Some countries will mark International Women's Day with a public holiday and celebrations. It's a sad truth that in many of those countries lesbians and bisexual women won't be able to take part in the festivities openly. But they they do have a voice.

At the ongoing 57th meeting of the UN Commission on the Status of Women lesbians and bisexual women will be promoting awareness of their concerns and challenges. We hope the Commission will be listening.