Although plenty of bizarre things can happen to your body during pregnancy, many mothers will tell you the cravings they experienced were among the strangest side effects of all. Some are more common than others, from unlikely sweet-and-savory combinations to junk food on top of junk food. Meanwhile, some cravings are truly one of a kind (shout out to the woman who only yearned for squid and milk).Some women even confess to enjoying the foods they craved after giving birth. While it's perfectly fine to indulge in the occasional peanut butter, ham, and cheese sandwich, women with more esoteric cravings should probably think twice, specifically those who admit to eating clay or chalk while pregnant. In spite of Shailene Woodley's hearty endorsement , this practice, known as pica in the medical parlance, is the one craving you should ignore. Eating clay, chalk, or sand can interfere with your ability to absorb nutrients from other foods, ultimately leading to a deficiency that's bad for you and the baby, according to the American Pregnancy Association.That said, if you feel the urge to eat any other "non-food" substances you shouldn't panic. It does happen to some women. While it's unclear why exactly pica occurs, some experts think it might have to do with low iron levels or another deficiency, which your doctor can monitor and advise you about.Below, we've rounded up 20 women's weirdest pregnancy cravings, posted to the secret sharing app Whisper . These prove once and for all that, like so many snowflakes, no two pregnancies are alike, right down to what you eat during yours. Don't blame us if you find yourself craving nachos and maple syrup by the end of this post.