The sudden death of Saskatchewan curler Aly Jenkins due to an amniotic fluid embolism sheds light on an extremely rare and serious obstetric condition that doctors have no way to foresee.
Ms. Jenkins, 30, died Sunday while giving birth to her third child, a girl named Sydney. Her husband told a Saskatoon radio station she was fine when she arrived at hospital, but began feeling cold during labour and within several hours, her heart gave out. Her infant daughter Sydney was placed in neonatal intensive care, he said.
Amniotic fluid embolism (AFE) occurs in an estimated one to eight cases per 100,000 deliveries, but is considered one of the major causes of maternal mortality in industrialized countries, says epidemiologist Sarka Lisonkova, an assistant professor in the department of obstetrics and gynecology at the University of British Columbia.
The causes of this condition, whose symptoms include shortness of breath and cardiorespiratory collapse, are not entirely understood. Previously, it was believed AFE occurred when fetal cells or amniotic fluid entered the mother’s blood system, causing an embolism, or blockage, in the lungs, Dr. Lisonkova said. However, over the past decade, scientists have challenged this idea, noting there would be insufficient amniotic fluid in the mother’s system to create a large enough embolism to cause a sudden collapse, she said.
Moreover, fetal material can enter the mother’s blood stream in normal pregnancy and especially during normal delivery, as the barrier between mother and infant is disrupted, Dr. Lisonkova said.
Instead, it is now believed AFE is likely a reaction of the mother’s immune system to the fetal material. Thus, calling it an embolism is somewhat of a misnomer.
“It’s still recognized that there’s contact with amniotic fluid and/or fetal cells; it’s just not an embolism. … It’s a hypersensitivity reaction,” said Michael Kramer, professor in the department of pediatrics and epidemiology at McGill University.
Dr. Kramer said it is not difficult to recognize AFE when it happens, but it occurs with very little warning, and there is no way of testing for it in advance.
Doctors can respond by giving the mother fluid if her blood pressure is too low, making sure she gets enough oxygen and giving her clotting factors to control bleeding, he said. But even so, he said, “it’s often just catastrophic.”
The fatality rate for the mother is about 15 per cent to 20 per cent, while the baby dies twice as often, he said.
Jennifer Blake, chief executive officer of the Society of Obstetricians and Gynaecologists of Canada, said Canada needs a consistent way of measuring and reporting maternal deaths.
Some areas of the country, for instance, only report maternal deaths in the first 42 days after giving birth, while some provinces report them after the first three months after giving birth.
The current available data suggest there are around 11 maternal deaths per 100,000 live births in Canada, Dr. Blake said, noting the rate appears to be on the rise, likely owing, in part, to substance abuse, mental-health issues and superbugs, or multidrug-resistant infections.
However, she said, because of the lack of solid, accurate data, the true scope of the problem is unknown.
“When you lose a mother, it impacts the family, it impacts the community. It’s the most devastating loss,” Dr. Blake said. “We strongly believe that there should be no preventable maternal deaths in a country with the resources Canada has.”
But in cases of AFE, she said, “It’s an unforeseeable complication. It’s a tragic event, but it can’t be predicted.”