Most Common causes of Miscarriage

Miscarriage is a term used to describe a situation in which a pregnancy loss takes place spontaneously within the first 20 weeks of gestation. It is also known as a ‘spontaneous abortion’ although the previous term is preferred by many clinicians due to the inadvertent anxiety associated with the term ‘abortion’ among pregnant mothers. According to statistics, around 10 to 25% of all pregnancies will end-up in a miscarriage although large number of these females would not be aware about the occurrence of a miscarriage or even the fact that they were pregnant.

As pointed out by obstetric experts, most miscarriages take place within the first 12 weeks or in other words within the 1st trimester. Most 1st trimester miscarriages results from various abnormalities in the fetus itself. When it comes to second trimester miscarriages or in other words, in late miscarriages, the underlying cause will most likely to be related to the mothers health or to the abnormalities within the uterus itself.

Common causes for 1st trimester miscarriages

During the first 12 months, the most important determinant of fetus viability is its chromosomal arrangement. These chromosomes are made up of genetic material known as DNA strands and both parents will be contributing to the chromosomal constituency of the fetus. If the chromosomal pattern is incompatible with life, the body will automatically mark the fetus as ‘non-viable’ and will spontaneously give rise to a miscarriage. Thus, the commonest cause for miscarriages during the 1st trimester is the chromosomal abnormalities.

During the fetal growth, the structure that supplies the fetus with the necessary amounts of blood is the placenta. If the placenta is abnormal and does not perform its function accordingly, it will not be possible for the fetus to sustain life and therefore a miscarriage might take place.

Apart from these two main causes, certain other factors will increase the likelihood of an early miscarriage. Among these factors, increasing maternal age, obesity, smoking, heavy alcohol intake, heavy caffeine intake and drug misuse can be highlighted.

Common causes for 2nd trimester miscarriages

According to the UK National Health Services website, the commonest cause for 2nd trimester miscarriages or late miscarriages is long term health conditions. Among these chronic health conditions, diabetes, severe high blood pressure, kidney diseases, lupus, over activity or under activity of the thyroid gland and celiac disease are frequently noted. In addition to long term health conditions, infections such as rubella, cytomegalovirus, toxoplasmosis, HIV, syphilis, malaria and Chlamydia can also lead to miscarriages during the second trimester.

Certain medications can also increase the risk of 2nd trimester miscarriages and some of the well known drugs that can cause miscarriages include misoprostol, retinoids, methotrexate and non steroidal anti-inflammatory drugs. However, there may be many other drugs, which can increase the risk of miscarriage during this period, and therefore pregnant mothers should be careful when taking over the counter medications and prescriptions medications during this time.

In addition, experts have recognized that the structure of the womb and the cervix can also affect the continuity of a pregnancy and therefore could be the cause for a miscarriage.