If you\u2019ve experienced the heartache of a miscarriage, you probably wondered whether something you did \u2014 or didn\u2019t do \u2014 is to blame. The truth is, most miscarriages are random events that occur because the fetus isn\u2019t developing normally.\nAccording to national statistics, as many as one in five known pregnancies end in a miscarriage, defined as the spontaneous loss of a pregnancy before 20 weeks. That number is likely much higher, occurring in women who lose the fetus before ever realizing they were pregnant.\nCommon Miscarriage Myths\nMyth 1: Say no to sex\nContractions resulting from orgasms may scare you, but they won\u2019t cause a miscarriage. The baby is fully protected by the amniotic sac and strong uterine muscles. But it\u2019s still important to use safe sex measures like condoms to protect yourself and your baby against sexually transmitted infections.\nMyth 2: Stop working out\nMost experts agree that exercise during pregnancy \u2014 with your doctor\u2019s okay \u2014 is good for you and your baby. It can help you stay in shape and prepare for labor and delivery.\nMyth 3: Don\u2019t stress out\nEvery expectant mom experiences worry and stress \u2014 over money, marriage, work, traumatic events, even family tragedies. You\u2019ll get through it, and your baby will, too.\nMyth 4: Don\u2019t lift your toddler\nPicking up that youngster will not do any harm to your unborn baby. But, to prevent injury to your back make sure you squat to pick up your toddler \u2014 and use your legs.\nMyth 5: The baby \u201cknew\u201d it wasn\u2019t wanted\nBabies are often unexpected. But feeling ambivalent about the pregnancy, or thinking about having an abortion, doesn\u2019t cause the baby to die.\nKey Miscarriage Facts\nAccording to the American College of Obstetrician and Gynecologists, approximately 60 percent of miscarriages occur when an embryo has an abnormal number of chromosomes during fertilization \u2014 a problem that happens by chance, not as a result of anything the parents did.\nMaternal health conditions such as hormonal problems, infections, and diabetes, also can play a role, but in many cases, the causes are simply unknown.\nMiscarriage Risks\nOther factors linked to an increased risk of miscarriage include:\n\nAge. Women over age 35 have a higher risk of miscarriage than younger women. Paternal age also may increase risk.\nLifestyle factors such as smoking, using illegal drugs, and heavy alcohol use.\nWeight, including being underweight or overweight.\nInvasive prenatal tests.\nExposure to radiation and toxic substances.\n\nTo learn more, or to schedule an appointment with an OB\/GYN near you, call 1-866-MyMagee (696-2433) or visit the Magee-Womens Hospital of UPMC website.\nWant to learn more about maternal fetal medicine and preterm birth? Check out our\u00a0Medical Monday\u2019s post on Newborn Medicine.