From Resolve.org, Myths and Facts about Infertility:

Myth: It's all in your head! Why don't you relax or take a vacation. Then you'll get pregnant!
Fact: Infertility is a disease or condition of the reproductive system. While relaxing may help you with your overall quality of life, the stress and deep emotions you feel are the result of infertility, not the cause of it. Improved medical techniques have made it easier to diagnose infertility problems.

Myth: Don't worry so much -- it just takes time. You'll get pregnant if you're just patient.
Fact: Infertility is a medical problem that may be treated. At least 50% of those who complete an infertility evaluation will respond to treatment with a successful pregnancy. Some infertility problems respond with higher or lower success rates. Those who do not seek help have a "spontaneous cure rate" of about 5% after a year of infertility.

Myth: If you adopt a baby you'll get pregnant!
Fact: This is one of the most painful myths for couples to hear. First it suggests that adoption is only a means to an end, not an happy and successful end in itself. Second, it is simply not true. Studies reveal that the rate for achieving pregnancy after adopting is the same as for those who do not adopt.

Myth: Why don't you just forget it and adopt? After all, there are so many babies out there who need homes!
Fact: For many, adoption is a happy resolution to infertility. However, most people explore medical treatment for infertility prior to considering adoption. In addition, traditional adoption options have changed, and adoption can be more costly and time-consuming than expected. It is, however, still possible to adopt the healthy baby of your dreams. There are also many older children and children with special needs available for adoption.

Myth: Maybe you two are doing something wrong!
Fact: Infertility is a medical condition, not a sexual disorder.

Myth: Perhaps this is God's way of telling you that you two aren't meant to be parents!
Fact: It is particularly difficult to hear this when you are struggling with infertility. You know what loving parents you would be, and it is painful to have to explain to others that you have a medical problem.

Myth: Infertility is nature's way of controlling population.
Fact: Zero population growth is a goal pursued in a time of world overpopulation, but it still allows for couples to replace themselves with two children. Individuals or couples can certainly elect the option to be childfree or to raise a single child. Infertility, for those who desire children, denies them the opportunity to choose.