She did not, however, think her answer would get her fired.
In April 2009, Hamilton told her boss at Southland Christian School in St. Cloud, Fla., that she was pregnant and planned to take a six-week leave in October. When asked when she conceived, Hamilton answered honestly: She became pregnant just three weeks prior to her Feb. 20 wedding.
That was enough to get her fired under the school's strict morality rules, which prohibit teachers from "fornication," engaging in sex before marriage.
"Jaretta was asked not to return because of a moral issue that was disregarded, namely fornication, sex outside marriage," administrator Julie Ennis wrote in a letter to Hamilton's lawyer.
Now, Hamilton is suing the school in federal court, seeking damages for lost wages and emotional distress.
"She was incredibly upset about being fired," Hamilton's lawyer Edward Gay told ABCNews.com. "She was upset that she wasn't able to complete the term with less than two months left in the school year and upset that her fourth graders were told about this."
According to Gay, Hamilton filed a complaint with the Equal Employment Opportunity Commission, but opted out of mediation and chose instead to file suit because of the commission's lengthy backlog.
According to the complaint, Hamilton is suing under federal gender discrimination laws, a state marriage discrimination law and for violations of her privacy.
"The school told the students and their parents why Hamilton had been fired. Disclosing that kind of personal information was a violation of her privacy," Gay said.
"There were never any complaints about her teaching. The school said she was an outstanding teacher," he added.
The school does not dispute the reasons for firing Hamilton, calling sex outside of marriage "an immoral action," but argues that her termination does not rise to discrimination because it employs other pregnant women.
In a letter to Gay, school administrator Julie Ennis wrote: "Jarretta was asked not to return because she chose to disregard these [school morality] standards and have sex outside of marriage, an immoral action."
"In response to the first claim that she was fired because she was pregnant this is not true," Ennis wrote. "We do have teachers employed that are pregnant, two just last year while Jarretta was employed here."
When reached by ABCNews.com, Principal Rod Ennis, Julie's husband, said the school had no comment, but was surprised to learn Hamilton had opted out of the EEOC mediation.
"At this point, we're not making any comment," said Rod Ennis. "We were aware of the EEOC and were going to go to mediation."
Gay said Hamilton learned she had become pregnant only after she and her husband married and the wedding had been planned months in advance.
"She was intending on marrying this man and didn't know she was pregnant," he said. "They didn't get married because of the pregnancy. They didn't know until later, after they were already married."
The school, despite being a private religiously affiliated institution, is not exempt from federal discrimination laws, Gay said.