Sarah Harding has admitted that she cries when thinking about never having children of her own.
The Girls Aloud singer, 39, is currently battling breast cancer which has spread to her spine and is undergoing treatment, including having recently had a mastectomy.
Writing in her new book Hear Me Out, Sarah discussed the impact that chemotherapy to treat her cancer has had on her hopes for motherhood.
She notes that three of her old bandmates - Nadine Coyle, Cheryl, and Kimberley Walsh - have had kids or are due to have more children imminently.
In an extract from her book, Sarah penned: "I was saying how we never thought Nadine would be the first one of us to have a child, and that now three of them have kids."
She noted: "It might seem odd to worry about not having children when I don't even know how much of a life I have left, but it's there."
Sarah comments that even if her health outlook was better, her cancer treatment has put a stop to her hopes of having kids.
"The truth is, even if my prognosis was better, it still wouldn't be on the cards because of all the chemotherapy I've had," she reveals.
"That treatment, harsh as it is, will have killed any chance I might have had. It's making me cry just thinking about it."
The singer also reflected on her former five-year romance with DJ Tom Crane, calling their split "the biggest mistake of my life".
Amidst these hard times, Sarah was pleased to find that her book Hear Me Out has topped book charts on Thursday.
Sharing a photo of the chart-placing on Amazon Book charts on Instagram, she penned: "OMG thank you so much everyone!! [love heart emoji, prayer hands emoji]".
Her bandmate Kimberley also shared a shot of the music charts as fans worked to get Girls Aloud song Heart Me Out to the top of the iTunes singles charts.
Kimberley posted: "This is amazing! What a lovely thing you guys are doing Sarah will love this!"
*Hear Me Out by Sarah Harding is available now.
If you have been affected by this story, call Macmillan Cancer Support on 0808 808 00 00 or visit the website here.
