Erika Mitchell was nearing her sixth month of pregnancy when she knew for certain something was wrong.

The feeling had started to build earlier in her pregnancy, but doctors assured her the breathing issues and exhaustion she was experiencing were normal.

With three healthy pregnancies in the past, Mitchell, 37, wasn't convinced.

"I was having so much difficulty breathing that I couldn't sleep," recalls the Clio, Michigan, resident. She also had a lingering cough. She was diagnosed with bronchitis, but the prescribed medication didn't improve her condition.

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When she began to retain fluid in her legs, Mitchell's obstetrician again attributed it to the pregnancy, assuring her, "This is all normal."

By July 2017, at seven months of pregnancy, Mitchell's fluid retention was becoming unbearable.

"I couldn't eat and was losing weight. My body felt so overworked," she says. "I thought I was going to die."

With fear mounting, Mitchell and her fiancé, Jon, went to the emergency department of a local hospital, where she was admitted to the maternity ward for testing.

"I hadn't slept in two weeks and felt awful, but no one was listening to me," she says. "They told me a lot of people were coming in with breathing problems because of the extreme hot weather."

A breakthrough and answers

Things changed for Mitchell when a nurse noticed her struggling to walk from the hospital bathroom to her bed, unable to catch her breath.

"She told me, 'This isn't normal,' and called in a cardiologist," Mitchell says.

An echocardiogram revealed a low ejection fraction — the percentage of blood moving from the heart each time it contracts. A low ejection fraction is often an indication of heart failure. Mitchell was rushed to Michigan Medicine, known for its highly skilled team of experts in high-risk pregnancies and cardio-obstetrics.

Tests there confirmed peripartum cardiomyopathy (PPCM), a rare form of heart failure that develops toward the end of pregnancy or several months after giving birth. As the heart muscle weakens, fluid begins to back up in the lungs and legs, making it difficult to breathe and causing swelling. In severe situations, the heart may not be able to meet the demands of the body's organs for oxygen.

SEE ALSO: Women with Congenital Heart Disease: Safe Pregnancy Is Possible

Similar to Mitchell's experience, symptoms of PPCM include extreme fatigue, severe shortness of breath (especially at night and when lying flat) and swollen legs (often swollen from the feet to the knees). Other symptoms may include heart palpitations, a rapid heartbeat and chest pain.

A difficult diagnosis

"Peripartum cardiomyopathy often goes undiagnosed because there is so much overlap with the symptoms of a normal pregnancy," says Michigan Medicine cardiologist Melinda Davis, M.D., who specializes in pregnancy and women's cardiology. "This is why the condition is commonly misdiagnosed."

Davis reminds women that this is a rare condition, and many women may have mild symptoms such as shortness of breath and swelling related to a normal pregnancy. Her goal, however, is to increase awareness of PPCM and the symptoms women need to be concerned about.

Although the incidence of PPCM seems to be rising, she says it's hard to know if this is because the condition is, in fact, becoming more prevalent or diagnosis techniques have improved.

Davis recommends that women who are experiencing extreme symptoms talk with their doctors about further testing, noting that the condition is often a diagnosis of exclusion.

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"Women can be tested for fluid overload from the heart to rule out PPCM," she says, adding that a blood test to measure the B-type natriuretic peptide hormone can be useful, and an echocardiogram can measure the heart's ejection fraction to determine if heart failure is the cause of the symptoms.

Even though the majority of PPCM patients don't have a genetic history of cardiomyopathy, Davis stresses the importance of knowing your family's health history. In Mitchell's case, for example, her father's death of cardiomyopathy suggests a genetic link to PPCM.

Unlike Mitchell, who was diagnosed during her pregnancy, most women are diagnosed after delivery.

"Often after pregnancy, there is a lot of fluid absorbed by the body, causing symptoms to worsen after delivery and resulting in heart failure from peripartum cardiomyopathy," Davis says.

She advises women to talk with their doctors about any severe breathing difficulties or fluid retention issues in the weeks and months after delivery.

Treating PPCM

PPCM patients are often hospitalized until their symptoms are managed. Treatment can include diuretics, or water pills, to relieve fluid retention and swelling. Beta-blockers and ACE inhibitors can help the heart beat more efficiently, but ACE inhibitors cannot be used until after pregnancy.

"Women should consult with their doctor about which medications are safe during and after pregnancy and compatible with breastfeeding," Davis says.

Mitchell remained hospitalized and monitored for several weeks until her condition stabilized. Six weeks later, on August 12, 2017, she gave birth to a healthy son named Raymond.

With the knowledge that PPCM patients have a significant risk of recurrent heart failure and other complications if they become pregnant again, Mitchell says this will be her last pregnancy.

"I don't want to go through that again," she says.

"Patients whose heart function does not improve after treatment are at a high risk for severe complications with another pregnancy," Davis says. "Some women whose hearts fully recover might consider another pregnancy, but the risks should first be discussed with their doctors. Women who have had PPCM should see a cardiologist on a regular basis to monitor heart function and discuss ongoing use of medications."

Davis says her most important message to pregnant women is simple: "If you're worried, don't hesitate to ask your doctor. Advocate for your health."

Mitchell agrees. She shares her story with the hope that she can increase awareness of PPCM, thankful that her challenging health scare is behind her as she looks forward to another cherished Mother's Day celebration.