The 37-year-old — known for the BBC's satirical sketch show The Mash Report — spoke to Kate Thornton on White Wine Question Time about losing her first baby during the early months of the pandemic in August 2020.
Parris also praised the doctors and midwives who looked after her in the hospital, where she had spent a couple of weeks waiting to hear if her daughter had died before being born, saying she 'couldn't get over how amazing' they were.
She told Thornton: "It was really the darkest thing that we could have imagined happening with our pregnancy.
"It was it was a such a sad and tragic thing that was happening. And I just couldn't get over how amazing the people in the hospital were."
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While she said she knew there was no 'hierarchy of pain', Parris said she's since heard of so many people going through later still births, adding: "I can't imagine that."
The couple now have a son, Billy, who was born in 2021.
Thornton read an extract from Parris's book — Advice from Strangers — which was partly gathered from audience suggestions over a tour before the comedian was due to give a talk at her former school.
The extract said: "When the baby came, we held hands and we cried. The midwife who had been with us all day, and who delivered the baby, cried with us."
Thornton said she read it 'time and time again' because every time she did her eyes 'were just blurred with tears'.
She added: "But what overwhelmed me was the the incredible kindness of strangers in the most profoundly difficult circumstances."
Describing the time in the lead up to the birth, Parris said different staff would react in different ways, with some being more positive and upbeat, and others being 'more realistic'.
"It was impossible to know which way it would go," she said. "It was just hope and despair, on and on for for weeks.
"And then there was this one night where it became clear what was going to happen, and it was going to happen soon, and that baby couldn't make it."
She said the doctor who explained things to her was amazing, doing it 'so clearly and so compassionately'.
Remembering one midwife called Anna, who the couple are still in touch with, she said it was like 'having your mum there.
Parris said: "She was able to just hold me when I was crying. And she was there the next day, it wasn't just when it was happening, it was in the days afterwards.
"And they all they all kept in touch with us. They were there all the time afterwards. And we're still sending her pictures of Billy now."
She said they would still see Anna at the hospital throughout her pregnancy with her son Billly, and that when they saw her during a scare at 21 weeks — the same time they had lost their daughter — it was 'like a sign, like an angel'.
"She wasn't meant to be [at the hospital]," Parris said. "She just saw Marcus in the corridor crying and she came to find me.
"We needed her most of all, of everyone. We needed her so much that day. And it was so scary, we thought it was all going to happen the same again.
"And she was there for us. And little things like that were really amazing."
If you've experience baby loss or want any support on the issues raised, you can visit the Sands website.
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