Recently I was reading sociologist Mark Regnerus’s insightful new book Cheap Sex: The Transformation of Men, Marriage, and Monogamy. His premise is that the Pill and ubiquity of pornography have caused sex to be more widely available, which drives the cost of sex down and makes real commitment more “expensive” and difficult to navigate. Essentially, Regnerus examines sex in America today through an economic lens.

Perhaps the most interesting part of the book was his final eight predictions for 2030 in regard to sex, relationships, and marriage. He admits that these are “educated guesses” and that the evidence for some is better than for others. Even though he is confident they won’t all come true, they are based on his best reading of current numbers and trends.

Prediction #1: Sex Will Get Even Cheaper. Regnerus considers this one “easy.” Fertility control is improving and there is little risk of pregnancy with sex. Porn use also continues to grow and shows no signs of declining. The continued growth of erotic experiences through porn will continue to cheapen the real thing. Eventually porn will be taken for granted. And as a result, there will be more loneliness, since solitary sexual experiences simply cannot fulfill our deepest needs.

Prediction #2: Enforcement of Age of Consent (Sexual) Laws will Decrease. This is perhaps one of the most startling of his predictions, but Regnerus does note that the age of consent is up for grabs. He is not predicting that American parents will embrace adolescent sex, but that there will be less enforcement age of consent laws near the legal age. In fact, he predicts that prosecutors will not wish to press charges unless the victim is clearly pre-pubescent.

Prediction #3: The Percentage of Unmarried Americans Will Increase, but the Age of First Marriage for Women Will Slow. Demographers predict that the share of Americans who never marry will continue to increase. Women no longer need men for social, cultural, and economic reasons, and men no longer feel the need to act “nobly” towards women and their interests. Regnerus predicts we are moving towards a nation that increasingly replaces marriage relationships with partnering singles (and he believes this will make our nation remarkably lonely and vulnerable).

Prediction #4: Same-Sex Marriage Will Decline Among Gay Men. Regnerus believes the legalization of same-sex marriage in 2015 was more a sign of deinstitutionalization than the revitalization of marriage. Given the propensity of men towards non-monogamy, he believes far fewer gay couples will choose marriage (unless, of course, in the unlikely event that marriage is transformed to integrate non-monogamy). Regnerus concludes, “By 2030, there is a good chance that a look-back at June 2015 will reveal same-sex marriage as a quest for rights and a cultural land grab rather than a product of the genuine desire to access a historic institution” (p. 207).

Prediction #5: Men’s Sexuality Will Become More Malleable. According to Regnerus, scholars are beginning to reveal that men exhibit a greater degree of sexual malleability than previously thought. He expects men to increasingly experiment with same-sex sexual behavior while not identifying as exclusively gay. He believes this is due to the declining stigma of non-heterosexual identities, increasing emphasis on a variety of sexual experiences, and the ubiquity of pornography that blends straight, gay, lesbian, multi-partner, and other forms of sexuality.

Prediction #6: Organized Christianity Will Not Stem the Retreat from Marriage in the U.S. While American Christians value lifelong monogamy, according to Regnerus, few have the commitment to make a significant cultural difference. One reason is that the evangelical church is decentralized. And the other reason is that many Christians have bought into the cultural emphasis on individualism and self-fulfillment at the expense of biblical teaching.

Prediction #7: Polygamy Is Not Coming Back, but Polyamory May Become an Accepted Minority. According to Regnerus, long-term legal shifts in family laws favor the individual, not the kinds of unions they form. Americans are more interested in fleeing marriage than having multiple marriages (at least in significant numbers).

Prediction #8: Efforts to Abolish Gender Will Not Succeed. Such efforts may have some success, but ultimately Regnerus concludes, “Because while the globe’s inhabitants may exhibit sympathy for the equal treatment of its citizens, and perhaps efforts to ensure equal economic access, they have much less patience for efforts aimed at obliterating all sexual difference—that is, eradicating the truth of sexual dimorphism” (p. 212).

Even though these are reasonable predictions, it is impossible to know what the future will hold. I have some intuitions about these trends but don’t have a crystal ball.

Nevertheless, they will certainly be on my personal radar as I both study and have conversations about the future state of love, sex, and marriage in America. I hope you will be following these trends as well, and be thinking about what they mean for Christian faithfulness and cultural engagement in the years to come.

Sean McDowell, Ph.D. is a professor of Christian Apologetics at Biola University, best-selling author, popular speaker, part-time high school teacher, and the Resident Scholar for Summit Ministries, California. Follow him on Twitter: @sean_mcdowell and his blog: seanmcdowell.org.