Adapted from The Fertility Diet (McGraw-Hill) by Jorge E. Chavarro, M.D., Walter C. Willett, M.D., and Patrick J. Skerrett.

If you have been having trouble getting pregnant—or getting pregnant again—forget about the so-called fertility foods like oysters and champagne, garlic, ginseng, kelp, and yams. The true fertility foods are whole grains, healthy fats, excellent protein packages, and even the occasional bowl of ice cream. This isn't just wishful thinking. Instead, it comes from the first comprehensive examination of diet and fertility, an eight-year study of more than 18,000 women that uncovered ten evidence-based suggestions for improving fertility. This work, from the landmark Nurses' Health Study, fills a critical information gap on diet and fertility.

The recommendations that follow are aimed at preventing and reversing ovulatory infertility, which accounts for one quarter or more of all cases of infertility. They won't work for infertility due to physical impediments like blocked fallopian tubes. And they aren't meant to replace a conversation with a clinician about whether an infertility work-up is needed. The strategies described below don't guarantee a pregnancy any more than do in vitro fertilization or other forms of assisted reproduction. But it's virtually free, available to everyone, has no side effects, sets the stage for a healthy pregnancy, and forms the foundation of a healthy eating strategy for motherhood and beyond. That's a winning combination no matter how you look at it.

Avoid trans fats. These artery-clogging fats threaten fertility as well harm the heart and blood vessels. Go trans free.

Use more unsaturated vegetable oils. Monounsaturated and polyunsaturated fats help improve the body's sensitivity to insulin and cool inflammation, two trends that are good for fertility. Add in more vegetable oils, nuts, seeds, and cold water fish such as salmon and sardines. Cut back on saturated fat.

Turn to vegetable protein. Replacing a serving of meat each day with beans, peas, soybeans or tofu, or nuts can improve fertility.

Choose slow carbs, not no carbs. Choosing slowly digested carbohydrates that are rich in fiber, like whole grains, vegetables, whole fruits, and beans, instead of rapidly digested carbs can improve fertility by controlling blood sugar and insulin levels.

Make it whole milk. Skim milk appears to promote infertility. If you drink milk, choose whole milk while trying to get pregnant, or have a small dish of ice cream or full-fat yogurt every day.

Take a multi-vitamin. Getting extra folic acid (400 micrograms a day) before you get pregnant could actually help you start eating for two.

Get plenty of iron from plants. Extra iron from plants, including whole-grain cereals, spinach, beans, pumpkin, tomatoes, and beets, appears to promote fertility.

Drink to your health. The best beverage for keeping your body hydrated is water. Coffee, tea, and alcohol are okay in moderation. But skip sugared sodas—they appear to promote ovulatory infertility.

Head toward the fertility zone for weight. Weighing too much or too little can interrupt normal menstrual cycles, throw off ovulation or stop it altogether. The best range for fertility is a body-mass index (BMI) of 20 to 24. Working to move your BMI in that direction by gaining or losing some weight is almost as good.

Move to the fertility zone for activity. If you don't get much physical activity and are above the fertility zone for weight, daily exercise can help improve fertility. But don't overdo it: too much exercise, especially if you are quite lean, can interfere with ovulation.