Your man's fertility may be linked to, of all things, the health of his bones. That's what researchers at Columbia University Medical Center think after research with laboratory mice found that a hormone released by bone, known as osteocalcin, appears to boost testosterone production, the main sex steroid hormone controlling male fertility.
Published online February 17, 2011, in the journal Cell, the study showed that when levels of osteocalcin went up in mice, so did their levels of testosterone. On the other hand, when mice had low or no levels of osteocalcin, testosterone levels dropped—as did sperm count and fertility, researchers found.
Though the findings have not yet been confirmed in humans, researchers expect similar results due to similarities between mouse and human hormones. If future studies do confirm the connection between osteocalcin levels and testosterone, study authors are hopeful their discovery may explain why some infertile men have unexplained low levels of testosterone.
How can your guy take better care of his bones? Eating a balanced diet that is filled with healthy sources of calcium, magnesium, vitamin D, and other key nutrients for bone health can help. As can exercise. Simple weight-bearing exercises, like walking or running, can improve bone density and bone function, as can skipping, heel drops, and jumping rope. And it's good for you too! Making sure your skeleton is in tip-top shape before pregnancy is an important part of reducing your risk for osteoporosis later in life.