The 45-year-old shared a touching video from her wedding to the British chef, with whom she has five children, on Instagram.
In the video, the newlyweds can be seen dancing to Dusty Springfield’s ”I Only Want to Be with You”.
In the caption, Mrs Oliver praised her husband for being her “best friend” and lamented the loss of “their five little stars in the sky”.
“20 years married Today !! 20 exciting, happy, fun wonderful years married to my best friend... we were due to renew our wedding vowels this summer but that can wait!” she wrote.
“20 years married but together 27 years my first true love... Yes I drive you Bonkers and you probably deserve a medal etc...”
Mrs Oliver continued: “But being with you feels like home (and you know much I love to be at home)!!! I treasure the daily texts you send, you are romantic and constantly positive funny and a dedicated brilliant dad...
“We have created five wonderful children and lost our five little stars in the sky. Thank you for loving me the way you do...”
The video that Mrs Oliver posted has garnered more than 188,000 views so far and more than 1,500 comments from fans congratulating her on the wedding anniversary but also thanking her for being so open about baby loss.
“It’s like something out of Love Actually,” commented one person in reference to the couple’s wedding video.
Mrs Oliver first opened up about the miscarriages during Baby Loss Awareness Week.
Last October, she shared a photo on Instagram of a candle next to pictures of loved ones and wrote in the caption: “A wave of light for all the families who have been affected by baby loss in any way.
“Our candle shining brightly as always for our lovely friend’s little baby Archie, always remembered, and friends who I know who have lost their precious babies. And to us, our little stars in the sky shine bright. Xx.”
You can find out more information on baby loss and where to find support by visiting Tommys.org.