LEAH Messer claimed she miscarried her first child with former husband Jeremy Calvert on a season four episode of Teen Mom 2, but she admitted she lied and actually had an abortion in her upcoming memoir.

The Sun can exclusively reveal an excerpt from Hope, Grace & Faith, where Leah, then 19, admitted for the first time that she aborted her baby because she was conflicted over her relationship with ex-husband Corey Simms.

6 Leah Messer had an abortion despite claiming she suffered a miscarriage on Teen Mom 2 Credit: MTV

Leah, now 27, explained in the book, which is out May 5, that she began dating Jeremy soon after her divorce from Corey, who she shares 10-year-old twin daughters Ali and Aleeah with, even though she “definitely wasn’t over” him.

When Corey learned of the new relationship, he started having “second thoughts” about the divorce as well, and the two began discussing if they should give their marriage another shot.

Despite being “twisted up in knots" over Corey, Leah moved in with Jeremy and he proposed.

Weeks later, she learned she was pregnant with their child.

6 Leah was conflicted over her feelings for ex-husband Corey

She wrote: “I was devastated. Having a baby with Jeremy would be the end of any chance Corey and I had of making things work for our family. I was sad for myself, but mostly I was sad for our girls. I knew I had f**ked up, and I felt like I had ruined their lives on top of mine.”

In the memoir, Leah claims her rep at the time encouraged her to terminate the pregnancy. Leah believed the rep's advice was to help save her “public image.”

To make matters worse, Leah explained how she was in a bad place with Jeremy because of her feelings for Corey.

When she told her mom Dawn, she said she would “support” whatever decision she made, but that Jeremy could not find out if she chose to terminate the pregnancy.

6 Leah filmed the "miscarriage" on the show Credit: MTV

Leah’s mom and rep “came up with a plan” to make it look like Leah was “having a miscarriage.”

The MTV star claimed in the book that she took pills from a clinic, and started having heavy bleeding and cramping.

Her mom then called Jeremy.

Leah wrote in the memoir: “When she told him I was having a miscarriage the way she played the role of concerned mother was so damn convincing even I couldn’t tell she was lying.

“I remember listening to her talking to Jeremy on the phone and wondering how the hell I had let this happen.”

6 Leah even kept the abortion from Jeremy Credit: MTV

The situation became “real” for her when she saw the sac with an embryo inside of it.

She wrote: "It was the worst thing I had ever been through.”

When she called producers that night to tell them she lost the baby, they sent a camera crew and filmed about the “miscarriage.”

Leah penned in the memoir: “I can look back now without regret, but for the longest time, I wasn’t okay with the choice I had made. It felt so dark because it was hidden.

“It wasn’t until I was finally able to bring myself to tell Jeremy what had really happened that I started to realize that as long as I was living with the lie it would keep eating away at me. I carried the pain and the guilt around with me for years, until I finally got to the point where I could hold myself accountable for my choices without punishing myself for them.”

6 Leah and Jeremy have been on-and-off since the divorce Credit: Instagram

She said that to this day, she isn't sure if Corey knows the truth.

But the abortion didn’t help her reconcile with Corey, as she married Jeremy in 2012.

They welcomed daughter Addie, 7, in 2013.

She admitted that she “just settled” with him and they divorced in 2015.

6 Leah shares daughter Addie [middle] with Jeremy Credit: Instagram

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On the season four premiere of Teen Mom 2, Leah said: “This morning I had really bad cramps and was bleeding so I went to the hospital. Jeremy was away at work. But he came home as fast as he could.”

When Jeremy asked what the doctor said, she responded: “They just said that um, they guess I lost it. By the time I got there I bled everywhere.”

She then said: “I just don’t understand why.”

Jeremy responded: “It was out of the blue. There was nothing leading up to it. It just happened.”

Leah said: “I just want it back.”

Leah and Jeremy have been on-and-off since the divorce.

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