From 1993's “Dazed and Confused” to 2012's “Ted,” smoking marijuana has long been a favorite Hollywood shortcut to dumbed-down, cheap-shot humor.

But for couples struggling with conception, weed is nothing to laugh about. In fact, it sends their chances of having a baby up in smoke.

In an article published in the Canadian Medical Association Journal, researchers say they want doctors and patients trying to have a baby to be aware that smoking marijuana may make it more difficult.

Why? Because THC, the psychoactive ingredient in marijuana, affects receptors in the hypothalamus, pituitary gland, and reproductive organs, making it more difficult to conceive.

In women, the hypothalamus produces gonadotropin-releasing hormone, which leads to a cascade of other hormones needed for ovulation, as well as preparing the uterus for a fertilized egg.

In addition, problems with the pituitary gland can contribute to erectile dysfunction in men and infertility in women.

Another problem: decreased sperm count. A Danish study published in the American Journal of Epidemiology found that smoking marijuana more than once a week reduced sperm count by 29% in guys 18 to 28 years old.

Marijuana may also delay or prevent ovulation if smoked more than three times in the past three months.

And one more caution: Authors of a study called “Not Your Mother's Marijuana,” published in Clinical Perinatology, point out that if you're pregnant and smoke today's super-powered weed, prenatal exposure to marijuana can result in problems with your child's executive functioning skills, attention, behavior, and school achievement later on.