What Can Cause a Miscarriage

The medical definition of a miscarriage is the spontaneous loss of a pregnancy before 24 weeks' gestation, but miscarriages can occur anywhere before the end of the gestation period of nine months. Most miscarriages occur before the 13th week of pregnancy and can occur in about 15-20% of pregnancies, irrespective of the health of the woman as well as the fetus. This is a statistic that most expecting couples are aware of causing them apprehensions, but before one gets too worked up, it is best to understand the reasons behind it.

Causes of Miscarriage

A woman's body undergoes many changes much before she gets pregnant. Through natural processes the uterus, fallopian tubes, etc all gear up for the fertilization of the egg. However, sometimes the body rejects some of the mechanism early on in the pregnancy stage or for some at a later stage. In most cases of pregnancy a miscarriage is sudden and unexpected, while in some expecting a miscarriage is almost part of being pregnant.

During First Trimester: The most sensitive period is early after implantation, and during the first 14 weeks where there is a 30% chance of a miscarriage. Most of these miscarriages are caused due to a chromosomal abnormality; a genetic problem that occurs during the crossover of genes from the sperm and the egg takes place at the time of conception. This abnormality may or may not occur due to a parent's genes. However, there is no way of ascertaining that chromosomal abnormalities will recur.

Another reason for an early miscarriage includes the age of the mother, too young as well as older women carry a higher risk of miscarrying, or could also happen in the case of repeated miscarriages, or if one of the parents has a child or an extended family member with birth defects. Progesterone deficiency is seen as another cause of an early miscarriage, however, research is yet inadequate to endorse that progesterone supplements could reduce the risk of miscarriage. There is another reason defined as a chance event, where miscarriages can be attributed to no known medical cause.

During the 2nd and 3rd Trimester: In most cases the risk of miscarriages reduces substantially during the second trimester. However, the risk is still present. Miscarriages during this period are caused by physical problems such as structure of the womb (uterine malformation), the strength of the cervix holding the weight of the growing pregnancy, or growth in uterine fibroids, problems with the umbilical cord, and a significant number of late term miscarriages occur due to problems with the placenta function. Miscarriages are less common in the third trimester, and those that occur are due to maternal as well as external factors, like ill health of the mother, excess stress, or a physical injury.

Certain Medical Conditions: There are many health conditions of a pregnant woman that can have a direct impact on the life expectancy of a fetus. Uncontrolled diabetes is seen as a major reason for the occurrence of a miscarriage. Women who have diabetes or later develop gestational diabetes must ensure adequate treatment. Hormonal disorders such as polycystic ovary syndrome, Cushing's Syndrome and thyroid disease may also cause a miscarriage. Fetal or placental infection, abnormal structure anatomy of the uterus, or the occurrence of fibroid tumors could add to the risk of a miscarriage. An ectopic pregnancy, usually ends in a miscarriage and damages the organ (where the egg gets fertilized) in the process. Autoimmune diseases and illnesses such as rubella, chlamydia, etc too are associated with an increased risk of miscarriage. High blood pressure during pregnancy, known as preeclampsia can also be a reason for miscarriage.

Lifestyle Factors: Lifestyle plays an important role in ensuring a healthy pregnancy. As food is very important to nourish the mother and the unborn child, it carries risk when one consumes food associated with miscarriages. Actually food does not cause a miscarriage, it is the immune system's reaction to it that can cause it. Avoid consuming shellfish, unwashed vegetables, raw eggs, processed foods that contain artificial additives, caffeine, etc. Prenatal exposure to smoking or substance abuse can not only interfere with the healthy development of the baby, but also lead to miscarriage. Alcohol consumption can result either in Fetal Alcohol Syndrome, other developmental disorders, or a miscarriage. Stress is also believed to be one of the causes for a miscarriage, but this factor still needs more study.

Reasons of miscarriage in a perfectly healthy pregnancy is still baffling to most doctors and researchers. Precaution against environmental factors and management of infection and disease is all one can do, while hoping against a miscarriage.