I actually did a science experiment in High School where I tried to affect a hamster's offspring genders through diet. It worked so well I tried it with myself to conceive a boy, and it worked!
It's not fool-proof (nothing is), but it's worth a shot, right? Apparently, the x-chromosome thrives in an acidic environment, and the y-chromosome thrives in an alkaline environment. So, if you and your husband look up and eat foods that create an acidity (safely) - it should help influence that x-chromosome. We started changing our alkalinity (for a boy) several months before conceiving.
Here's a small list of acidic foods I found:
Corn
Meat
Beans
Fish
Fowl
Most grains
Coffee
Plums
Prunes
Cranberries
Distilled water
Eggs
Liver and other organ meats
Gravy
Broth made from bones or other animal parts
Wine
Yogurt with active cultures
Buttermilk, including buttermilk pancakes and biscuits
Sour cream
Most fermented foods and aged cheeses
Some B vitamin supplements (or foods supplemented with B vitamins) can make your stomach more acid
Hydrochloric acid supplements
Digestive enzymes
And foods that are more alkaline:
Most fruits, except as noted above
Most vegetables, except as noted above
Bananas
Chocolate
Figs
Mineral water
Orange juice
Potatoes
Spinach
Watermelon
Dandelion Greens
Good luck!!!