If you are planning a pregnancy, it is likely you want to achieve or maintain a good body weight and overall fitness level before conceiving. According to a study published in April 2008 -- conducted by a group of medical researchers from a university hospital in Montpellier, France -- a pregnancy is more dangerous for the mother and baby if the mother is overweight or obese at the time of conception. Although running and jogging are both excellent forms of exercise for fitness and weight control, the type of running you do can affect your chances of getting pregnant.
A study published in the "Journal of Obestetric, Gynecologic and Neonatal Nursing" surveyed 319 women runners who were running at a relatively high level of intensity. The women studied completed both a 10K -- 6.2 mile -- run and a full marathon -- 26.2 miles. It was found that these intense runners often experienced skipped, scant or irregular menstrual periods. Therefore, intense running may reduce the number of menstrual periods you have, which could make it more difficult to get pregnant. However, the study found that intense running did not have an effect on long-term fertility.
Intense running activity may also temporarily reduce male fertility. MayoClinic.com reports that if a man exercises to the point of exhaustion, this may cause a temporary reduction in the quality of his sperm. This is due to the ability of exercise to temporarily change your hormone levels. However, moderate to vigorous exercise -- when you do not exercise until you are completely exhausted -- is beneficial for male reproductive health as well as general health.
Intense running -- at high speeds and/or over long distances -- is considered potentially dangerous during pregnancy. If you are trying to conceive, you might want to reduce the intensity of your regular running in order to reduce any possible danger to the fetus. Typically, a woman will have been pregnant for up to several weeks before she realizes that she is pregnant. During this time it is important not to jeopardize the pregnancy with high-impact exercise. However, according to a 1993 study at Indiana State University, it was found that a woman can return to high-intensity running and training shortly after giving birth.
Once you have conceived, jogging may be beneficial to your baby's development. Medical News Today reports that a 2006 study at the University Medical School in Berlin, Germany, found a difference in the neuronal cells of the brain in the offspring of mice who exercised during pregnancy. In comparison to the offspring of mice who were inactive during pregnancy, the offspring of the active mice had a 40 percent increase in cell development in the hippocampus, an area of the brain involved in memory and learning. However, it should be noted that this study has not been repeated with human subjects, and results in mice cannot be assumed to correlate to similar results in humans.
Every person's body, health history and pregnancy experience is different. If you are a runner and are planning a pregnancy, you should talk to your doctor before attempting to conceive. Your doctor can give you individualized medical advice relevant to your medical history and current state of health.