April 25, 2012 -- A Catholic school teacher in Indiana is suing a diocese there, claiming that she was unlawfully terminated after school officials learned she was undergoing fertility treatments to become pregnant.

In a federal lawsuit filed in a Fort Wayne, Ind., teacher Emily Herx claimed that she was fired and told by a senior church official that her attempt to become pregnant through in-vitro fertilization made her a "grave, immoral sinner."

Between 2003 and 2011, Herx, who taught literature and language arts at the St. Vincent de Paul School, was well regarded, receiving high marks when evaluated by administrators, according to court documents.

In 2010, Herx, who is married, learned that she "suffers from a diagnosed medical condition which causes infertility" and told the school's principal she would be undergoing IVF treatments, according to court documents.

At the time, the principal told Herx "You are in my prayers," and allowed her to take time off to receive treatments, according to court documents.

One year later in May 2011, after requesting time off for a second round of fertility treatments, she was told to report to Msgr. John Kuzmich, the pastor of the St. Vincent de Paul Catholic Church.

At that meeting, attended by Herx, her husband and father, Kuzmich called her a "grave, immoral sinner" and added that if news of her IVF treatments got out it would cause a "scandal" for the church, according to her civil complaint.

Kuzmich allegedly said the church disproved of fertility treatments because they require the creation of additional embryos that are ultimately destroyed, a violation of Catholic teachings regarding the sanctity of embryonic life.

According to her civil complaint, Herx explained that no embryos were destroyed during her treatment, but diocesan officials were not swayed.

Herx made a final appeal to Bishop Kevin Rhoades, but he too refused to reinstate her, the suit alleges.

Rhoades told Herx, "The process of in vitro fertilization very frequently involves the deliberate destruction or freezing of human embryos," adding, "In vitro fertilization ... is an intrinsic evil, which means that no circumstances can justify it," according to the civil complaint.

Herx filed a complaint with the federal Equal Employment Opportunity Commission and won, opening the door to a civil lawsuit, according to her lawyer Kathleen DeLaney.

Herx was "terminated only for trying to enlarge her family with husband," DeLaney said, calling her firing a "traumatic event" for the teacher.

The Supreme Court recently ruled that the religious institutions are exempt from discrimination laws in hiring clergymen. A Catholic church for instance cannot be sued for failing to hire women priests because it conflicts with fundamental Church doctrine.

DeLaney told ABC News, that she does not believe the court's decision applies to Herx.

"The facts in this case are distinguishable. There is no ministerial exception. Ms. Herx didn't have religious training, did not teach religious doctrine," she said.

DeLaney would not confirm whether Herx has since become pregnant.

A spokesman for the Fort Wayne-South Bend Diocese said he was unable to comment on a pending lawsuit.

"It's sad day for our diocese and the St. Vincent's family. We're asking for prayers for our diocese and the Herx family," spokesman Sean McBride told ABC News.