Miscarriage means loss of an embryo or fetus before the 20th week of pregnancy. Most miscarriages occur during the first 14 weeks of pregnancy. The medical term for miscarriage is spontaneous abortion. Miscarriage also means expulsion of pregnancy before the fetus becomes viable. In this article, you will learn the common causes of miscarriage.
The chance of having a miscarriage drops as the pregnancy progresses. Miscarriages are most common in the first trimester. The chance of having a miscarriage after 14 weeks is 1%. However, for women greater than 40 years the chances of having a miscarriage at 12 weeks can still be as high as 10.8%.
Causes of miscarriages include;
- Age; the older a woman gets the higher the chances of having a miscarriage. According to Anne-Marie Nybo Anderson, of the Danish Epidemiology Science Centre, the chance of having a miscarriage rises sharply when a woman is in her late 30s and reaches nearly 100% by age 45. It has also been found out that there is a 60% increase in the odds of a miscarriage if the father is over 40years old. All these results due to a decrease in the quality of eggs and sperms released with the associated increase in age.
- Chromosomal abnormality; about half of the spontaneously occurring abortion result due to the defect in the chromosome of the embryo. The body has a way of ejecting malformed embryos very early in pregnancy. Examples of such chromosomal abnormalities include; Turners syndrome, Down syndrome, Patau syndrome.
- Infection: Both preexisting infections prior to pregnancy and infections early in pregnancy can lead to a miscarriage. A woman with untreated gonorrhoea, chlamydia and mycoplasma infection is more prone to miscarriages. Mumps or rubella disease in early pregnancy can also lead to miscarriage.
- Hormonal imbalance: As seen in patients with polycystic ovarian syndrome (PCOS), insufficient progesterone which causes problems with implantation can all result in reoccurring miscarriages.
- Medical conditions such as diabetes, thyroid disorders. When patients do not manage these conditions properly, they make the uterine environment un-conducive for the embryo to develop. Some other medical conditions that can predispose to miscarriage include; hypertension, coeliac disease.
- Uterine abnormality and incompetent cervix: The presence of septa in the uterus can predispose to miscarriage. This is especially when the embryo is implanted on it. Also, the presence of fibroid in the uterus (womb) can predispose to miscarriages due to insufficient nutrient delivery to the fetus.Normally the opening of the cervix is closed. However, if due to some factors such as instrumentation, the opening of the cervix which guards the uterus remains patent, the developing embryo can easily be expelled/released from the uterus.
- Immunological disorders: Such as antiphospholipid syndrome results in multiple miscarriages. The body sees the sperm or developing embryo as a foreign object and decides to attack it leading to a miscarriage.
- Medications: Certain medications can increase the chances of having a miscarriage. Examples of such medications include; ibuprofen, steroids, antidepressants, warfarin.
- Lifestyle; smoking, excessive alcohol consumption or takes illicit substance increases the chances of having a miscarriage. Nicotine crosses the placenta and interferes with blood supply and fetal growth. Also, smokers have twice the rate of miscarriage as nonsmokers.Women exposed to high levels of toxic chemicals like bisphenol A (BPA) found in plastics are 83 percent more likely to have a miscarriage than women with lower levels.
- Body weight; obesity increases the chances of having a miscarriage. Underweight women are also 72 percent more likely to suffer a miscarriage during their first 3 months of pregnancy, compared with women whose weight was healthy.
As devastating as a miscarriage is, it is important to know that there are tests and treatments available that can help you have a healthy pregnancy and a healthy baby in the future.