The birth of a baby is supposed to be one of the most joyous moments of a new mom's life.

But for one in seven new mothers, it's a time that can be filled with sadness, loneliness and a detachment from their newborn. 

Baby Mave is Brooke Wiesner's third and youngest child. Although she loves her new child with her whole heart, Brooke said she struggled with dark thoughts after Maeve was born.

“I didn't feel about her the way I felt like I should have felt about her,” Brooke said. “It was all I could do to get out of bed. I was having some pretty significant, like, suicidal ideations." 

It took months for broke to get diagnosed with postpartum depression. She was prescribed antidepressants, but nothing worked. That's why researchers at Johns Hopkins University are developing a first of its kind blood test that could help women like broke get diagnosed with postpartum depression even before giving birth.

Using blood samples, researchers found tiny sacs called extracellular vesicles, or EVs, that carry genetic material from the brain.  

“What we're finding is that these extracellular vesicles are releasing things… it looks like RNAs from the brain,” researcher Sarven Sabunciyan said.

Abnormal levels of these specific RNA molecules are linked to brain disorders like postpartum depression, schizophrenia, epilepsy and addiction. Scientists believe these molecules are the biological markers they need to identify these conditions earlier than ever before.

“If we can figure out which people are going to respond to what drugs, that'd be a big deal,” Sabunciyan said.

The scientists warn that the findings about depression might only apply to postpartum depression because they studied only women. In the future, researchers plan to use lab-grown brain cells to find similar markers for autism spectrum disorder.

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