Although infertility affects men and women equally, male infertility often goes undiagnosed due to embarrassment and denial, according to the National Infertility Association (NIA).

When a couple is having trouble getting pregnant, male and female partners should be tested for infertility. Forty percent of infertility cases are attributed to medical problems of the male reproductive system, including sperm production and delivery, sperm antibodies, hormone production, anatomical problems, illness, infection or medication, according to NIA.

"The ability to conceive, as well as the inability to conceive, are shared equally by the male and female partners," said Margaret Hollister, executive director for RESOLVE, the Web site for the NIA. "Many men feel their masculinity is threatened or have feelings of inadequacy if they are diagnosed with infertility. This can be an emotionally charged experience, yet our society often overlooks the needs and medical conditions associated with male infertility."

Today there are many effective treatment options that can turn want-to-be fathers into parents, including intracytoplasmic sperm injection which allows a single sperm to be placed directly into an egg for fertilization.

Women and men struggling with infertility can visit www.resolve.com. for more information.