Some people are arguing that the "Mother's Day" programme is widely abused, but the government is standing by the legislation that gives women a day off work every month during their period.
What is "Mother's Day" in Zambia?
Two years ago, the Zambian government revised its employment law to grant all women one day of menstrual leave each month. This means that all women are entitled to a leave day during their monthly cycle.
An umbrella body of Zambia's action groups, the Non-Governmental Organisations' Coordinating Council (NGOCC) called Mother's Day a "progressive law".
"Some women have heavy flows, some of them have a lot of pain or vomiting," one member of the group, Madube Siyauya said.
"So it's a very important day that allows women to attend to their biological needs and continue their work without being susceptible to discrimination."
The legislation, also applies to women after menopause, when their menstruation ceases.
What is the argument against it?
Not everyone is a fan and the law is stirring increasingly fierce debate in a country that is reluctant to discuss sexual health.
Some Zambian women say the day off is widely abused.
"I have never taken 'Mother's Day' in my life," head of the Alliance for Community Action, Laura Miti said.
"I don't understand why others need it. It is abused. Whenever they have something they need to do, they would rather take the day off than taking leave."
"My sense is that giving half the workforce 12 days (off) extra per year is unproductive. It can't be productive, especially if you are working in the corporate world."
Chiselwa Kawanda, 33, a government employee in Lusaka, agrees, saying the law was misguided.
"If I miss a day at work, it means I have to start all over the next day," she said, adding that, in any case, "You don't have periods for just one day."
What do supporters say?
A 36-year-old civil servant and a mother of three from the capital Lusaka said the day off helps her manage her "physiological needs".
"As a woman, it goes without saying that every month I need a special day away from the office to manage myself properly."
Some Zambian women also say that employers, particularly in the private sector, put pressure on female workers to not take their "Mother's Day".
Is it affecting productivity?
The government thinks it does not.
"Of course there has been some complaints here and there but women go at different times. There is no documentary evidence of low productivity," an official from the labour ministry Cecilia Mulindeti-Kamanga said.
"Some women get sick, they are not able to concentrate on their work ... so it was agreed that they can stay home without producing any certificate."
Do other countries have similar policies for women?
Zambia's approach is rare.
Japan adopted similar legislation in 1947 and Indonesia, Taiwan and South Korea have since followed suit.
In Britain, Coexist, a small Bristol-based non-profit company, is experimenting with flexible hours for menstruating employees.