Jessica Wilson with her husband, Nick, and children, Theodore, 2, and Rosalynn, 18 months. Wilson, who is expecting her third child, is one of a small but growing number of conservative Christians who are questioning the use of hormonal birth control. Caleb Drahosh Photography

Jessica Wilson got married five months before she graduated from an evangelical college in 2010. Because she believed that sex is reserved for marriage, it wasn’t much earlier that she had started thinking about what kind of birth control to use. No one in her family or her church had ever questioned the idea of contraception, but they hadn’t taught her much about it, either.

Eventually she came upon the writings of Randy Alcorn, an author and activist who promotes the idea that hormonal birth control, like the pill and some intrauterine devices, sometimes works as an abortifacient by preventing the implantation of a fertilized egg. Alarmed, she decided she couldn’t take that risk, especially since she had already heard horror stories from friends who said the pill made them gain weight, diminished their sex drive or caused depression. She began charting her menstrual cycles, haphazardly at first, and when she got married she used a diaphragm with spermicide when she thought she was ovulating. All three of her pregnancies, including those that resulted in a son and daughter born 15 months apart, were unplanned, but she says she has no regrets.

“I have seen a lot of people [questioning] the idea in our culture that couples deserve to have five years of freedom before they have kids or this unwritten code that all Americans should have two boys and a girl and then they’re done,” she said. “Why are we buying this idea that we shouldn’t have kids?”

Surveys indicate that the vast majority of both Catholic and Protestant married women have used or are currently using contraception. But Wilson is part of a conversation percolating among some adherents of both traditions, most of them educated and conservative, that suggests a growing moral discomfort with birth control. These are not like the Duggar family (of reality television’s “19 Kids and Counting”) who believe that constant childbearing is a Christian obligation, and not all of them reject birth control wholesale. Some simply don’t like the idea of interfering with a woman’s natural bodily rhythms, or they fear, like Wilson, that hormonal contraception has the potential to cause very early abortions. And others share a broader concern: that the underlying logic of contraception suggests couples can, and should, rigidly control their fertility — and that children are not a blessing, but a burden to be avoided.

Among conservative Protestants, these are sprouts of doubt around a topic that hasn’t been debated seriously for decades. “Contraception has been an ingrained, unquestioned, binding reality on young evangelicals,” said Andrew Walker, director of policy studies at the Southern Baptist Convention’s Ethics & Religious Liberty Commission. Growing up in the evangelical community, “there was just the assumption that you get married, you use contraception, no doubt about it.”

Walker, now 29 and the father of two daughters, got married at 21 and didn’t question at the time whether his wife would go on the pill. Today, he still doesn’t believe that contraception is categorically sinful, but his wife no longer uses hormonal birth control, and he has larger concerns about what he calls “the contraceptive mindset.” “The idea of talking about children as a ‘scare’ and viewing them as an obstacle to the American dream, that’s not a Christian way of looking at family,” he said. “That’s what I like to tell young couples: The family is actually a pretty adaptable institution. It doesn’t necessarily have to put a brake on your life.”

Walker says he’s not alone in this thinking. “In more intellectual evangelical circles there’s a growing reticence, and a growing — not questioning the all-out use, but questioning the worldview,” he said. He first started to reconsider his acceptance of contraception as a graduate student at the Southern Baptist Theological Seminary, whose president, R. Albert Mohler Jr., has been an influential critic of what he calls “the contraceptive revolution.” (Wilson, too, cited Mohler’s writing on the subject in describing her own evolution.) As Mohler put it just last year, “Today’s generation of evangelicals is indeed reconsidering birth control, and theological concerns are driving that reconsideration.”

Few, if any, are convinced that evangelicals will turn against contraception in significant numbers. In 2002, a young evangelical couple, Sam and Bethany Torode, wrote a much-discussed book titled “Open Embrace: A Protestant Couple Rethinks Contraception.” Amy Laura Hall, an associate professor of Christian ethics at Duke University, said the book resonated with her students at the time. “There was a sense that something was wrong if there was this much pressure on exactly how many children you should have and exactly when you have them,” she said. The couple later divorced, and Hall says her students more recently have seemed less inclined to reject contraception. (If students ask her about birth control in class, she recommends a diaphragm with spermicide, explaining that it introduces women to their own bodies and also avoids artificial interruption of the “ebb and flow of desire.”)

But Hall, the author of the 2007 book “Conceiving Parenthood: American Protestantism and the Spirit of Reproduction,” worries that creeping criticism of “contraceptive culture” misses the point. She says most young couples delay childbearing not because of the existence of contraception but because of complex, real financial pressures. And she’s also concerned that conversations about a theologically proper approach to contraception make life difficult for young married couples. “It puts so much pressure on women’s bodies to be rightly ordered for the sake of the future,” she said. “All this pressure of getting it right — that can’t be what God means us to be doing with our beautiful minds and bodies.”