Lusaka - The birthday of twins Karen and Kelly Junior will always be tinged by sadness as it also marks the day their mother died in childbirth - a tragic occurrence of increasing public debate in Zambia.Their mother, Karen Kalengele, 33, was admitted to the Medcross hospital in Lusaka, one of the country's most prestigious private medical facilities, on March 18 to give birth.Her labour was slow and, as she was expecting twins, doctors chose to perform a Caesarean section.It was apparently successful but, soon after the birth, her husband Kelly Chuunga, 45, was informed of her death."We were with my sisters in a room where the babies had been brought and we were busy taking pictures while my wife was dying on the operating table," Chuunga, a finance manager, told AFP.For any explanation, he relies on a death certificate that concludes his wife succumbed to a pulmonary embolism -- a sudden blockage of an artery in the lungs.'Every death of a mother is one death too many'"I don't know whether it was negligence or it was an accident. It has left me with a lot of questions I don't have answers to," he said, adding he didn't want to pursue a legal case against the hospital.No-one at Medcross was reachable for comment when contacted by AFP.The reluctance to discuss or complain about cases of maternal death in Zambia has been challenged recently by the death of 29-year-old journalist Sithembile Zulu, who worked for the government-run Daily Mail.She died in September after giving birth to a girl in Lusaka, prompting an outcry in the media and triggering widespread demands for better understanding of maternal deaths.Health Minister Chitalu Chilufya ordered an investigation into the case, saying he was "deeply shocked by the turn of events... every death of a mother is one death too many."Looking for answers The risks of childbirth are higher in sub-Saharan Africa than in any other part of the world, with 547 deaths per 100 000 births, according to the United Nations.But Zambia is far from the worst nation affected, with 224 deaths per 100 000 births - compared to 1,360 in Sierra Leone and 814 in west African powerhouse Nigeria."The maternal mortality rate in Zambia is still very high, though we have managed to reduce it," said gynaecologist Samson Chisele, vice president of the Medical Association of Zambia."We are implementing action to try to get it to less than 100 per 100 000 by 2021."But such efforts will be a struggle in a country where 60% of the population live below the poverty line and the public healthcare system is dire."Maternal deaths in Zambia are a result of delays - delays going to the health facility, delay to reach the facility and delay at the facility," Chisele said.'I will not go to court'Some locals now hope that more public discussion about mothers dying in childbirth will force the government to improve healthcare in Zambia, which has major copper resources and an economy growing at four percent a year.One fierce voice of defiance who is calling for change is Sandra Phiri, who lost her cousin Felicia Zulu in childbirth two years ago.Zulu, 33, died at the country's biggest health centre, the University Teaching Hospital (UTH) in Lusaka, one week after giving birth to a baby who passed away soon after birth.A spokeswoman for UTH declined to comment on the case when contacted by AFP, but Phiri has no qualms about demanding answers from the medical authorities."After the baby died, they could have at least saved her life," she said.Still deep in grief, Kelly Chuunga tries to remain positive."I will not go to court," he said. "The babies are fine and they are being looked after by my in-laws to whom I am very much indebted."