Mom Who Suffered From Same Pregnancy Condition as Duchess Kate Calls It 'the Scariest 39 Weeks of My Life'

Duchess Kate Middleton has begun canceling public appearances after Kensington Palace revealed she was pregnant with her third child.

As Duchess of Cambridge Kate Middleton reveals her struggle with severe morning sickness in her third pregnancy, a New Jersey mom who suffered from the same condition has branded it “the scariest 39 weeks of [her] life."

Read: What is Hyperemesis Gravidarum? Duchess Kate Suffering From Severe Morning Sickness With Baby No. 3

Kensington Palace announced Kate Middleton’s third pregnancy in a statement Monday, but also explained she is also struggling with hyperemesis gravidarum for the third time, forcing her to cancel a scheduled appearance that morning.

“Their Royal Highnesses the Duke and Duchess of Cambridge are very pleased to announce that The Duchess of Cambridge is expecting their third child,” a statement from Kensington Palace said. “As with her previous two pregnancies, The Duchess is suffering from hyperemesis gravidarum."

The condition is rare, affecting one in every 200 pregnancies.

Kellyanne Mulrain, 31, of Aberdeen, says she also struggled with the hyperemesis gravidarum two years ago, when she was pregnant with her son Randy.

“It was severe, it was scary and I felt really alone,” Mulrain told InsideEdition.com. “There were days and nights I legit thought I was going to die.”

She discovered she had the disorder when she checked herself into the emergency room for severe dehydration at 10 weeks.

Mulrain explained some of the conditions she experienced included lightheadedness, nausea, vomiting, fatigue, malnutrition, dehydration and weight loss, but the symptom that affected her pregnancy the most was depression.

“To get up out of bed, to shower and just do my daily routines around the house were extremely difficult,” she explained. “I didn’t have the energy and I was constantly not knowing if I was just going to throw up or pass out.”

To battle the condition, she said doctors put her on cancer grade anti-nausea medication she would have to take four times a day, knowing it could negatively affect her baby.

“It was constant worrying about whether Randy was going to be healthy, if he was going to survive, if I was going to survive,” Mulrain said.

Read: Twins Who Shared the Same Amniotic Sac in High-Risk Pregnancy Cuddled to Stay Alive

Mulrain, now a mental health advocate for postpartum depression, said she hopes Middleton will have a healthy pregnancy, and will speak out for other women suffering from hyperemesis gravidarum.

“It’s a very scary, isolating, dark place to be in your pregnancy,” she explained.

To find out more about getting help for about perinatal mood and anxiety disorders (PMAD), visit Postpartum Support International.

Watch: 5-Year-Old Boy Saves Pregnant Mom's Life by Remembering Catchy Jingle