A US woman gave birth to a boy not knowing that her fiance and her mother had died in a car crash while rushing to the hospital for the delivery.

Speed "appears to be a significant factor" in the weekend crash in southwestern Michigan that killed Emil Skokan, 34, and Peggy Nichols, 53, Kalamazoo County Undersheriff Paul Matyas said.

View photos Crystal Matrau-Belt, 24, weeps while holding her newborn son Jeremiah James Matrau-Skokan and is comforted by her uncle Michael Myers. Photo: Mark Bugnaski / Kalamazoo Gazette via AP More

Crystal Matrau-Belt gave birth to Jeremiah by cesarean section Saturday at Bronson Methodist Hospital. Due to high blood pressure, she was admitted Friday and her doctor decided to induce labour.

Skokan sent a text message, asking Matrau-Belt whether she needed anything.

He "just said, 'I'll meet you up there,' and that he loved me," Matrau-Belt told the Kalamazoo Gazette.

It was their last contact. A car driven by Skokan crashed into a tree in Comstock Township, near Kalamazoo.

View photos Ms Matrau-Belt described how excited her mother Penny was to finally meet her first biological grandchild, recalling how she'd 'never seen her so happy'. Photo: Facebook More

Just hours after giving birth, Matrau-Bell was delivered the raw news.

“I asked my stepdad, ‘Do you know where Emil is?’” she said.

“My dad said, ‘Honey, that’s what we need to talk to you about’.”

“I just all of a sudden had a sinking feeling something was wrong. I just didn’t know that it was my fiance and my mum,” she said.

View photos Jeremiah James Matrau-Skokan is held by his mother Crystal Matrau-Belt at Bronson Methodist Hospital in Kalamazoo. Photo: Mark Bugnaski / Kalamazoo Gazette via AP More

Ms Matrau-Belt described how excited her mother Penny was to finally meet her first biological grandchild, recalling how she'd 'never seen her so happy'.

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