So how about investing one dollar in family planning then? I'll get you back six dollars in savings on housing, water, health, productivity... you name it.
You simply can’t lose!
But we are losing.

Last month the Rio+20 summit – the UN conference on sustainable development attended by some 190 countries – reached a final agreement on a way forward for the world that actually slid backwards when it came to women, by all but removing family planning from the paperwork.

A cheery coalition including the Vatican, Malta, Syria, Egypt and Russia spoke against the inclusion of reproductive health in the agreement, meaning that contraception was nigh wiped out of the sustainability equation, negating the crazy notion that women (and men) should be able to plan their families.

Yes, this sweeping decision was made even though more than 200 million women worldwide want access to family planning services but do not have them; even though there are 75 million unintended pregnancies in the world each year; even though some 22 million women and girls have dangerous backstreet abortions annually; even though up to 75 000 women die due to unsafe abortion each year – even though, on a profit-and-loss-based agenda, family planning saves up to six dollars for every one dollar spent.

In 15 countries in sub-Saharan Africa women have an average of more than six children each, excluding other pregnancies, abortions, miscarriages and heartbreaking infant deaths. It’s just not sustainable, but there’s no other option when you’re an impoverished rural women in a contraceptive-free zone.

However, given the choice, women can and do limit their number of pregnancies, leaving more resources for their existing offspring’s nutrition, education and wellbeing.

A woman who can control her fertility is stronger and healthier too, as are her children.

Consider too that if the unmet need for contraception was fulfilled, over 70 million unintended pregnancies could be avoided each year.

Now that’s sustainability! So this week we have another chance to fix it because it's the London Summit on Family Planning, where a call will be made for commitment and resources to be poured into contraception.

And if sustainability and saving lives aren't enough impetus, dear World Leaders, then think of all that lovely money.