"I know you knew I was pregnant. It's my fault," she wrote in her letter.
She mentioned all the hashtags she'd used on Facebook and Instagram that gave away that she was pregnant.
She knew these companies knew she was pregnant because of her google searches for maternity wear and she knew she'd given Amazon her due date for the registry so it was not surprising that other tech companies like Facebook knew this too.
What she didn't understand, however, was how these clever algorithms could not figure out she'd had a stillbirth.
"Didn't you see me googling 'is this Braxton hicks' and 'baby not moving'?"
"Did you not see the three days of silence, uncommon for a high-frequency user like me? And then the announcement with the keywords "heartbroken" and "problem" and "stillborn" and the 200 teardrop emoticons from my friends? Is that not something you could track?"
Instead, when she picked up her phone after days of crying her eyes out over her loss, she found herself target of ads for parents of newborns.
She ticked "I don't want to see this ad" and was asked to justify, out of the many options available. Choosing the appropriate one - "it's not relevant to me" - only made things worse.
The algorithm had assumed she'd given birth to a healthy baby boy.
Every targeted ad was a reminder of the life her son would never have, of the experiences she'd never get to have with him.
"Please tech companies, I implore you, if you're smart enough to realise that I'm pregnant, that I've given birth, then surely you're smart enough to realise that my baby has died, and can advertise to me accordingly, or maybe just maybe, not at all."
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