She also told Sawyer that from her perspective, "Heather and I already are married. We have built a home and a life together. I hope I get to spend the rest of my life with her. The way I look at it is, we're just waiting for state and federal law to catch up with us."
As news of Cheney's pregnancy hit Washington today, it quickly emerged as an issue in the battle between entrenched groups representing differing views of morality in the country.
In an interview with ABC News, Janice Crouse, an official with the conservative advocacy group Concerned Women for America, called Cheney's pregnancy "wrong."
"They're deliberately bringing a child into the world without a father, leaving a great gaping hole," Crouse said.
"Father absence is the biggest problem we're facing in this country," she said, and "the root cause of all sorts of negative outcomes -- drug use, juvenile delinquency. You name it."
Similar sentiments were expressed by Robert Knight, director of the Culture and Media Institute of the Media Research Center.
"I think it's tragic that a child has been conceived with the express purpose of denying it a father," Knight said.
"Fatherhood is important and always will be, so if Mary and her partner indicate that that is a trivial matter, they're shortchanging this child from the start."
"Mary and Heather can believe what they want," Knight said, "but what they're seeking is to force others to bless their nonmarital relationship as marriage" and to "create a culture that is based on sexual anarchy instead of marriage and family values."
Conversely, Jennifer Chrisler, the executive director of Family Pride, an advocacy group for gay and lesbian parents and their families, seized upon Cheney's baby news to underline what she sees as injustice.
"As Mary and Heather enter into the life-changing roles of parents, they will quickly face the reality that no matter how loved their child will be -- by its mothers and its grandparents, aunts and uncles, cousins and close family friends -- he or she will never have the same protections that other children born to heterosexual couples enjoy," Chrisler said.
"Mary and Heather currently live in Virginia. Unless they move to a handful of less restrictive states, Heather will never be able to have a legal relationship with her child" because Mary Cheney will be the birth mother and Virginia does not recognize the legal status of same-sex couples.