In Kazakhstan women cannot bleed or stun cattle, pigs or small ruminants; in Vietnam they cannot drive tractors of 50 horsepower or more

EVEN as rich countries seek to rid workplaces of subtle gender bias, in many developing ones discrimination remains overt. According to the World Bank, women are barred from certain jobs in 104 countries (see map).

“Gender equality in labour law is associated with more women working and earning more relative to men,” says Sarah Iqbal of the Bank. Yet some countries publish lists of jobs deemed too dangerous for women (Russia’s 456 include driving a train or steering a ship). Others stop women from working in entire sectors, at night or in “morally inappropriate” jobs (in Kazakhstan women cannot bleed or stun cattle, pigs or small ruminants). In four countries women cannot register a business. In 18 a husband can stop his wife working.

The aim is often to protect the “weaker sex”. Some laws put women in the same category as children; they concern jobs seen as physically tough, such as mining, construction and manufacturing. Others relate to broader safety fears. In Mumbai, for example, female shopkeepers cannot work as late as male ones. Other laws are intended to protect capacity to bear children. “Such policies often have demographic motivations, especially in countries with low birth rates,” says Ms Iqbal.

Restrictions on night work originated in England during the Industrial Revolution. They were based on the idea that women not only were weaker and more vulnerable to exploitation than men, but also lacked competence to make valid choices. In 1948 the International Labour Organisation (ILO) still sought to keep women away from mines and industrial nightwork. Spain did not lift restrictions on female workers in mining, electricity and some construction jobs until 1995. Some bans on women’s work still in place in former colonies are remnants of the 1960 Spanish Civil Code, the Napoleonic Code or Commonwealth laws.

Some laws are of surprisingly recent origin: Vietnam’s ban on women driving tractors of 50 horsepower or more came into force in 2013. But on balance, the trend is towards liberalisation. In recent years Bulgaria, Kiribati and Poland have removed all restrictions; Colombia and Congo have got rid of some. Other countries have changed laws in light of technological advances that have made many jobs safer and less reliant on brute force, or have seen courts overturn bans as discriminatory.

Labour shortages are also leading to change. When many male miners left Marmato, in Colombia, to find better pay elsewhere, female replacements were tolerated, even though hiring them broke the law. Similarly, when male truckers in eastern European countries that joined the European Union left for western ones, pressure to let women replace them increased. And the end of a ban on women working nights in the Philippines in 2011 was cheered on by call-centres, which need staff during daytime in America and Europe.

Some sex-specific restrictions are called for, says the ILO, particularly in the case of pregnant and breast-feeding women, for example when working with chemicals. (Such temporary and specific precautions are not counted in the World Bank’s study.) But, concludes the ILO, blanket protective prohibitions are “increasingly obsolete”.