Valentine's Day allows us to show that romance is not dead. It's the opportunity - whether we are long married or still in the first flush of a relationship - to say how happy we are with our partner.
But there is nothing romantic about millions of child marriages that take place every year. New estimates show that, this year alone, 13.5 million girls under the age of 18 - that's 37,000 daily - will marry. And almost one third of them will be under 15. This is simply unacceptable. Children forced to marry before their bodies have matured, forced to abandon their childhood, too often forced out of school and into domestic servitude and isolation. Children being robbed of the right to pursue a destiny of their own choosing.
These marriages must not be celebrated. They need to be prevented.
The practice continues in more than 100 countries. The majority take place in Asia, with high prevalence in many African and Latin American countries. But we are increasingly hearing stories about girls and boys from countries closer to home being forced to marry. It is a truly global concern that requires a global solution.
Americans are expected to send 140 million Valentine's Cards this year. Without urgent action, that is about as many girls who will be married under age 18 in the coming decade: 146 million, according to the new estimates.
Being married so early can also lead to serious damage to the health of the girls - and of their babies. Far too often, pregnancy is the inevitable and life-threatening consequence of child marriage, and complications in pregnancy and childbirth are one of the leading causes of death among girls between the ages of 15 and 19 in the developing world.
But the damage child marriage causes goes far beyond these individual tragedies. It leads to a disastrous waste of talent and potential for families and societies.
Almost every country in the world has committed to ending child marriage. But national laws and international conventions have failed, so far, to halt this practice, or even reduce its scale. It is why UNFPA, the United Nations Population Fund, is using this Valentine's Day to underline the urgent need for renewed national and global efforts to root out child marriage.
Existing laws must be rigorously enforced, and any loopholes must be plugged. Social norms that lead to laws being ignored or flouted must be challenged to give girls the choice they deserve and which their human rights demand. Communities must be informed about the widespread benefits of marrying later.
But most importantly, girls must be supported to remain in school, and have access to information and services, particularly for their sexual and reproductive health. We also must support those already married as children, help them avoid becoming pregnant too early, and provide them with better care if they do.
UNFPA works around the world to end child marriage, particularly in the developing world, where 1 in 3 girls are married before turning 18. In doing so, we have found that, when given the option, girls decide to marry later.
But we will not bring about the changes in policies and priorities without your support. Everyone can help by posting a selfie holding up a placard saying, "#Idont" and tweeting it or sharing it on Instagram with this hashtag. Together we will show the world how much we care about ending this damaging practice. Help our children say "I don't" instead of being forced to say "I do."
Dr. Babatunde Osotimehin is a United Nations Undersecretary-General and Executive Director of UNFPA, the United Nations Population Fund.