It's only natural to worry a bit throughout your pregnancy -- after all, this whole baby thing is new, nail-bitingly unpredictable, and you just want so badly for it to go perfectly. And guess what? It usually does. Here, doctors explain the real facts about the things that freak you out most. Read on -- and heave a huge sigh of relief.

THE FEAR: I'll have a miscarriage.

THE (RELAX!) FACTS: It's unlikely. Most pregnancies result in healthy babies (less than 20 percent end in miscarriage), says Karyn Morse, MD, an ob-gyn at Cedars-Sinai Medical Center in Los Angeles. "Remember also that most miscarriages also happen within the first few weeks of pregnancy, when many women typically don't realize they're expecting and wouldn't know if they did miscarry. They'd just get a normal-looking period," she says. After your doctor can see a heartbeat (usually around 6 to 8 weeks) the risk of miscarriage drops to about 5 percent. And there's very reassuring news if you should have one. The odds of having a second miscarriage is very small -- less than 3 percent, says Diane Ashton, MD, MPH, deputy medical director for the March of Dimes. So what causes a miscarriage? Often, it's due to a chromosomal abnormality that prevents the fetus from developing normally, and miscarrying is totally unavoidable -- not because of anything you did or didn't do. But you can lower your risk by not smoking or drinking alcohol and cutting back on your caffeine intake (aim for 200 milligrams or less, or one large cup of coffee, a day).

THE FEAR: My morning sickness is terrible! My baby isn't getting enough to eat.

THE (RELAX!) FACTS: Pardon the comparison, but babies are very good parasites, says Dr. Morse. "They'll absorb all of the nutrition from the foods you do give them -- so even if you're living on only crackers and juice, you don't need to worry," says Dr. Morse. Dr. Ashton agrees: "Unless you're sick to the point that you become severely dehydrated -- and if you were you'd feel so lousy that you'd call your doctor anyway -- morning sickness isn't going to cause any nutritional imbalance or affect the fetus." Just be sure to take your prenatal vitamins and do the best you can, otherwise. "Eat small, frequent meals," adds Dr. Morse. "Little bites tend to be less overwhelming to your digestive system. And eating more often will keep you from getting too ravenous, which is when women tend to feel the most nauseous." If you constantly find yourself over the toilet bowl, your doctor may prescribe an anti-nausea medication that is safe for the baby. And hang in there: Most women are able to stomach a wider variety of healthy foods after about 16 weeks -- which is coincidentally about when your baby needs to start gaining more weight too.

THE FEAR: I'll eat or drink the wrong thing -- and harm my baby.

THE (RELAX!) FACTS: Women today feel a lot of pressure to do all the "right things" when they're expecting, says Dr. Morse. Beyond the basics like eating healthy and taking prenatal vitamins, pregnant gals today worry about every little "Is it safe?" question. But agonizing over every decision will drive you crazy -- and there's no need for it. Your doctor should outline the big no-nos at your first prenatal visit, and you can ask about any major concerns then. Remember, no one can possibly follow every rule and guideline to the letter. And here's the truth: "Even the risks associated from things like eating unpasteurized cheese or dying your hair during your first trimester -- both of which doctors advise against -- are probably very, very small, and we're just being extra cautious," says Dr. Ashton. So don't fret if you accidentally order a turkey sandwich (oops...forgot that cold cuts are off-limits!) or sip a glass of juice at a brunch, then realize it's unpasteurized. And hey, we bet your mom didn't do half the things you're doing for your kiddo -- and look how brilliantly you turned out.