Miscarriage is the loss of a pregnancy before 20 weeks of gestation. The causes of miscarriage are often not identified, but there are several factors that may increase the risk of miscarriage. Here are some of the most common causes:

• Chromosomal abnormalities: Chromosomes are blocks of DNA that contain instructions for a babys development. Sometimes, something can go wrong at the point when a person gets pregnant, and the baby gets too many or not enough chromosomes. If this happens, the baby cant develop properly, and it can lead to a miscarriage.

• Uterus or cervix problems: Certain uterine conditions or weak cervical tissues, also called incompetent cervix, might raise the chances of a miscarriage.

• Infections: Any infection that makes a person very unwell can cause a miscarriage. Milder infections that affect the baby can also cause a miscarriage.

• Hormonal problems: Hormonal imbalances can cause a miscarriage.

• Autoimmune disorders: Autoimmune disorders that may increase the risk of miscarriage include antiphospholipid syndrome and lupus.

• Smoking, alcohol, caffeine, and illegal drugs: People who smoke have a greater risk of miscarriage than do nonsmokers. Heavy use of caffeine or alcohol use also raises the risk. So does using illegal drugs such as cocaine.

• Weight: Being underweight or being overweight has been linked with a higher risk of miscarriage.

• Age: The risk of miscarriage increases as a person gets older. In women under 30, 1 in 10 pregnancies will end in miscarriage. In women aged 35 to 39, up to 2 in 10 pregnancies will end in miscarriage.

Its important to note that routine activities such as exercise, sex, arguments, and use of birth control pills before getting pregnant do not cause a miscarriage. If a person has an ongoing health condition, such as uncontrolled diabetes, they have a higher risk of miscarriage[[1]](https://www.mayoclinic.org/diseases-conditions/pregnancy-loss-miscarriage/symptoms-ca...