Whatever the reason, there's still this weird idea, even among secular people, that the inability to conceive children is not simply a medical problem. Rather, it's a clear sign that you're being judged by an angry deity. Articles and books on the subject assure readers that infertility is "not a curse," whereas it's difficult to imagine similar articles having to tell people not to worry because their restless leg syndrome is not caused by nightmare demons. And then there's those stickers people put on their cars telling everyone that "Children Are a Gift from God."
You don't see many bumper stickers saying "A Healthy Spine Is a Gift from God" or "Not Having Crohn's Disease Is a Gift from God," and that's because they're dickish things to say. People with terrible illnesses are having a hard enough time already. They don't need to know that the guy who just cut them off in traffic thinks they're sick because God is picking them last for his Health Dodgeball team. But when it comes to babies, the attitude is somehow still acceptable. I don't want to pick on American Christianity here, because pretty much every belief system is equally bad about this. Practitioners of Eastern religions will tell you you're barren because you haven't been meditating enough, Satanists will tell you it's because you're doing your black mass all wrong, and so on.
"Dammit, Phyllis, did you even BRING a goat?"
And even non-religious people give bad advice, because ...