When heads of state from the Group of 20 most industrialised nations gather for their annual summit in Mexico next week, there'll be four women in the family photograph. Take a look at national parliaments and corporate boardrooms across much of the G20 and the male-to-female ratio doesn't get much better - and in some cases it's a lot worse.

Yes, women's rights have come far in past decades but the statistics show we still live in a man's world.

Nowhere is that more apparent than in countries like India, where females are killed at birth and burned alive in dowry-related disputes, or in Saudi Arabia, where women are banned from driving and virtually every aspect of their lives is controlled by men.

The widespread practices of infanticide, child marriage and gender-based violence were the main reasons why experts ranked India the worst place in the G20 for women in a perceptions poll published today by TrustLaw, a legal news service run by Thomson Reuters Foundation.

In Saudi Arabia, which ranked second-worst, women only earned the right to vote in 2011, while Indonesia, which followed Saudi Arabia in the ranking, faces similar challenges to India in terms of child marriage, sexual trafficking, violence and exploitation.

At the other end of the scale, Canada ranked the best place to be a woman thanks to policies that promote women's freedoms and good access to education and healthcare, but experts noted that Canada still has a long way to go, particularly in terms of narrowing the gender pay gap that stands around 30 percent.

The lack of free healthcare in the United States kept it out of the top five best countries. It was also penalised by a number of experts for the mounting restrictions on abortion and other reproductive services being adopted at state level. The U.S. was ranked sixth by the 370 gender experts polled.

The survey paints a sobering picture but, unfortunately, not one that will get much attention at the G20 summit in Los Cabos, Baja California, on June 18-19, where the eurozone crisis is set to take centre stage.

Granted, there are other forums to discuss women's rights. But as someone who's reported on a few G20 meetings in the past, the stark contrast between the sumptuous resort hotel hosting the gathering and the dire conditions endured by women in some of these countries feels a little uncomfortable.

It feels more uncomfortable because I've spent the past few months helping to compile the G20 women's poll. As a journalist who's lived in, reported on or travelled to most of these countries, I already knew a lot of the facts. But speaking to gender experts about wife-burning or child marriage in India, trafficking in Russia or rape and HIV/Aids in South Africa has brought the grim reality home.

In G20 host Mexico, which polled 15th out of 19 countries of the G20 (excluding the European Union grouping), a culture of male chauvinism pervades and high levels of violence against women have been exacerbated by the drugs war. And, as I recall from living there between 1995 and 2000, there are pockets of extreme poverty that are a world apart from the capital's skyscrapers and aren't reflected in national indicators on health and education.

The murders of hundreds of women in the border town of Ciudad Juarez and stories - related by activists - of women taking contraception before passing immigration to guard against expected rape are particularly disturbing. Mexico, like a number of G20 countries, has a stark divide between the rich and poor and women are often on the losing end of that wealth gap.

Mexican President Felipe Calderon, who'll host the G20 summit, had said he wanted development to feature highly on the G20 summit agenda and sustainable growth is up for discussion.

This is a start, as it's clear there can be no effective development without women's rights and freedoms - a point made by journalist and author Nicholas Kristof who commented on the poll. India and Saudi Arabia, he said, "are trying to develop with one hand tied behind their backs".

What's also clear from the survey results is that neither wealth nor democracy guarantee women's rights and that what's written on paper - in the form of laws and international conventions - rarely reflects the reality on the ground. Laws are worth little without effective enforcement - the violence against women plaguing Mexico is a case in point - and without education and national buy-in.

The poll also shows the impact a female head of state can have on a country's global image. Germany was rated the second-best place to be a woman although its gender pay gap is higher than the United Kingdom and France, while it came last out of 11 developed and developing countries in terms of female corporate executives in a 2010 McKinsey study.

Similarly, Brazil has a female president but women occupy only 9 percent of seats in its parliament's lower house.

I spent nearly three years living in Brazil and five in Mexico but I've now been back in the UK for nearly a decade. Living here, it's become easy to take for granted my rights as a woman, even if Britain has its own challenges - the UK came third in the poll. But the research I've done on this survey in past months reminds me why it's important we all fight for those women who don't have it so good.

Katherine Baldwin freelances for Thomson Reuters Foundation and helped compile the women's poll.

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