Olympic heptathlon champion Jessica, who is expecting a baby with husband Andy Hill, announced the happy news in a statement issued today.
The 27-year-old, who married childhood sweetheart Andy in May, also explained that she will now miss out on the 2014 Commonwealth Games in Glasgow.
She said: "I have some very unexpected but exciting news to share – Andy and I are expecting a baby. We are completely overwhelmed, with excitement and a degree of anxiety that I am sure all first time parents will relate to.
"My plans for 2014 have been completely turned upside down, but having had a couple of weeks to think about things from a career point of view, I am 100% set on returning to full time athletics once our baby is born and go for a second gold medal at the Rio Olympics in 2016 - that challenge really excites me."
"But in the short term I will make our baby a priority and enjoy the whole experience as much as possible. I am sorry I won't be in Glasgow for the Commonwealth Games, but know it will be an amazing occasion. I will be at home awaiting the arrival of a little Ennis-Hill."
Congratulations Jessica and Andy!
Check out more stars who are expecting a baby in the gallery below:
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