Pregnancy may seem like the most natural biological process in the world, but it doesn't come all that naturally for some. According to the U.S. Department of Health and Human Services, an estimated 12 percent of American women (7.3 million) have difficulty getting pregnant or carrying a baby to term.

If you've been trying to conceive for months with no luck, you may feel like giving up. But there's no need to throw in the towel just yet. The National Women's Health Information Center reports that two-thirds of infertile couples successfully conceive after seeking treatment. In addition, the following tips may help boost your odds.

1. Raise your level of self-awareness.

While sperm can survive in the womb for up to five days, the egg is only viable for 24 to 36 hours, so knowing when that ovulation window opens is the key to conception. You can become well acquainted with your menstrual cycle if you keep written track of it for a few months. An egg drops about two weeks before the start of your period, so to pinpoint the height of your fertility each month, you should maintain a record of your daily basal thermometer readings; a slight rise in body temperature indicates that you are ovulating.

2. Give up any vices.

If you smoke, it's imperative that you quit-and the same goes for your partner. A study conducted by McMaster University and Hamilton Health Sciences in Ontario, Canada, found that women undergoing fertility treatments who smoked or lived with a smoker had much less success with getting pregnant than their smoke-free counterparts. Consumption of five or more alcoholic beverages a week can affect fertility as well, according to a Danish study published in the British Medical Journal.

3. Eat more zinc.

Upping your intake of zinc facilitates not only ovulation in women, but also semen production in men, according to the American Pregnancy Association, which recommends a daily allowance of 15 milligrams. Folic acid is also a necessary dietary component for both sexes: Scientists at the University of California at Berkley linked low levels of folic acid in men with decreased sperm count.

4. Keep an eye on your BMI.

Make like Goldilocks, and aim for the BMI that's just right for you (your doctor can help you determine this). In a recent issue of Alternative Medicine Review, researchers reported that just a 5 percent reduction in weight among obese women suffering from polycystic ovary syndrome resulted in an 82 percent reversal of ovary dysfunction. On the flip side, scientists have also found that a low BMI can compromise the hormone levels required to sustain a successful pregnancy.

5. Treat your mind as well as your body.

For the past 15 years, the Benson-Henry Institute for Mind-Body Medicine at Massachusetts General Hospital has been using stress-reduction techniques, such as yoga, to improve fertility. In one study, the institute reported that 34 percent of participants became pregnant within six months of completing the program. And according to the National Center for Complementary and Alternative Medicine, women undergoing in vitro fertilization treatments can increase their chances of conceiving with acupuncture.