Discussing female menstruation publicly is something of a taboo in Zambia.
This is no doubt why a provision in the country's labour law that allows female workers to take off one day a month is known as Mother's Day, even though it applies to all women, whether or not they have children.
The legal definition is not precise - women can take the day when they want and do not have to provide any medical justification, leading some to question the provision.
"I think it's a good law because women go through a lot when they are on their menses [periods]," says Ndekela Mazimba, who works in public relations.
Ms Mazimba is neither married nor does she have children but she takes her Mother's Day every month because of her gruelling period pains.
"You might find that on the first day of your menses, you'll have stomach cramps - really bad stomach cramps. You can take whatever painkillers but end up in bed the whole day.
"And sometimes, you find that someone is irritable before her menses start, but as they progress, it gets better. So, in my case, it's just the first day to help when the symptoms are really bad."
Women in Zambia do not need to make prior arrangements to be absent from work, but can simply call in on the day to say they are taking Mother's Day.
An employer who denies female employees this entitlement can be prosecuted.
Ms Mazimba's boss, Justin Mukosa, supports the law and says he understands the pressure women face in juggling careers and family responsibilities.
A married man himself, he says the measure can have a positive impact on women's work:
"Productivity is not only about the person being in the office. It should basically hinge on the output of that person."
But he admits there are problems with the current system in terms of losing staff at short notice and also the temptation for people to play the system:
"It could be abused in the context that maybe an individual might have some personal plans they wish to attend to so she takes Mother's Day on the day.
Not everyone is so supportive of Mother's Day, and there are many women among the critics.
Mutinta Musokotwane-Chikopela is married and has three children.
She has a full-time marketing job but never takes Mother's Day, arguing that it encourages laziness in working women.
"I don't believe in it and I don't take it. Menses are a normal thing in a woman's body; it's like being pregnant or childbirth," she says.
"I think women take advantage of that, especially that there's no way of proving that you are on your menses or not."
Ms Chikopela says the provision should have been made more clear in the law.
"The problem in Zambia is that we have too many holidays - including a holiday for national prayers. So I guess Mother's Day makes those that love holidays happy."
The Zambia Congress of Trade Unions (ZCTU), the umbrella body representing the country's workers, is also a supporter of the law.
But the entitlement "would have to be forfeited" if a woman were to take it on a day that she was not on her period, says Catherine Chinunda, national trustee at ZCTU.
"We have been educating women about Mother's Day, telling them that on that day, they are supposed to rest and not even go shopping or do other jobs because that is wrong," she says.
The law itself provides no guidance about what is allowed and it would appear that very few, if any, employers have internal policy guidance in that respect.
She dismisses the idea that men should also get a day off every month, as has been suggested by some:
"Men sometimes go to drink and miss work…. they don't know how it feels to be on menses."
But while praising the concept of Mother's Day, some argue that the reality is bad for business.
"Your superiors may have planned work for you to do and when you suddenly stay away from work, it means work will suffer, says Harrington Chibanda, head of the Zambia Federation of Employers.
"Imagine a company that has a number of employees and six or seven take Mother's Day on the same day. What will happen to productivity?" he asks.
Labour Minister Joyce Nonde-Simukoko, a former trade union activist, tells me that Mother's Day was initially informally observed in the 1990s before eventually being brought into law.
But she has stern words for anyone thinking of using the entitlement to bunk off work:
"If you absent yourself yet you are found in a disco house, then it will not be taken as Mother's Day.
"You shouldn't even leave town, be found doing your hair or shopping. You can be fired. For example, somebody was found farming after taking Mother's Day and she was fired."
One of the problems with the law is that it does not make this explicit, leading to confusion among employers and employees alike.
But perhaps even more than the practical benefits, it is the intention and the spirit of the legislation that many Zambians support.
As Linda Kasonde, president of the Law Association of Zambia, explains:
"The reason why mother's day is important within the Zambian context is that it recognises that women are the primary care-givers in our society - regardless of whether they are married or not."