India's decision to ban condom ads on daytime television drew widespread ridicule as a retrograde step that threatened progress on sexual and reproductive health. India's Ministry of Information and Broadcasting ordered television channels not to air condom adverts between 6 a.m and 10 p.m. as they could be "indecent" and "inappropriate" for children.

The ban in the world's second most populous nation has triggered widespread criticism from health experts and campaigners who are working to boost family planning and curb the spread of sexually transmitted diseases.

"If advertisements are a way to create the demand for safe sex and family planning, then we need to ensure that it is not stifled by restrictions," Poonam Muttreja, executive director of the Population Foundation of India, said in a statement. "The advisory by the Information and Broadcasting Ministry is poised to undo decades of progress on sexual and reproductive health."

Muttreja instead called for a sensitive approach, suggesting adverts – like films – be given certifications based on their content and allocated suitable time slots for broadcast.

India has more than 1.3 billion people, and is set to overtake China as the most populated country in the world by 2024, says the United Nations. A study published in Lancet Global Health online found that half of India's more than 48 million pregnancies in 2015 were unintended, and a third resulted in abortions.

Although less than 6% of Indian men use condoms, health experts say condoms are one of the most effective contraceptives – helping families to space children, as well as protecting against sexually transmitted diseases like HIV/AIDS. "The ban is regressive," said Koninika Roy from the Humsafar Trust, a charity that works on HIV/AIDS and with the LGBT community.

"People are having sex at a much younger age and these ads could be telling them about safe sex. Condom ads are not about titillation, they are not about sex but about safe sex." News of the ban sent social media users on microblogging site Twitter into a frenzy, with many deploying humour to voice their disapproval.

"No condom ad on TV from 6am to 10pm because kids watch TV at that time," tweeted comic and writer Atul Khatri from the handle @one_by_two. "If your kid watches so much TV maybe you needed that condom in the 1st place."