Miscarriage is defined as the loss of pregnancy before the age of viability. The age of viability is relative and it depends on the region and it is the age at which a fetus can be sustained outside of the womb. In many developed countries, the age of viability is seen as the gestational age of 20 to 24 weeks or fetal weight of 500 grams and above. Miscarriage is relatively very common as most women have experienced miscarriage during their reproductive years. However, most cases passes unnoticed by the women i.e. miscarriage occurring in the first month after pregnancy.
Miscarriage and abortion are synonymous to a medical practitioner whereas to the public, abortion is the interruption of pregnancy while miscarriage is the accidental or spontaneous loss of pregnancy.
Causes of miscarriage
- Genetic defects: this is the commonest cause of miscarriage during the 1st trimester. Such genetic defects are those that are not compatible with life and nature has a way of getting rid of such fetuses.
- Structural defects: defects of the uterus and cervix can cause habitual miscarriages. Such defects can be congenital or acquired as a result of a disease process.
- Hormonal deficiency: early pregnancy is sustained by hormones produced by the woman. These hormones prepare and sustain the uterus during pregnancy. Absence of progesterone causes habitual miscarriage.
- Chronic maternal illness: chronic debilitating illness like uncontrolled hypertension, diabetes mellitus, kidney disease, liver disease, heart disease and systemic lupus erythematosus are frequently associated with recurrent miscarriage.
Types of miscarriage
- Threatened miscarriage: this is a very common gynecological emergency with patients presenting with vaginal bleeding less than 28 weeks of gestation (or the age of viability), the bleeding is associated with abdominal cramps. Symptoms may resolve spontaneously in some women but some may proceed to lose the baby. In threatened miscarriage, the cervical os (mouth of the womb) is still closed and this can be seen during speculum examination by your physician. Once a diagnosis is made, you will be counseled by your physician on the outcome of the condition. Traditionally, bed rest and mild analgesia have been used but there is no evidence of improved outcome. It is worth mentioning that there is no treatment for threatened miscarriage.
- Inevitable miscarriage: this occurs as a progression of threatened miscarriage. At this stage, nothing can be done to salvage the pregnancy because the cervical os is already open. The patient may experience severe lower abdominal pain/ cramps and severe vaginal bleeding. Diagnosis can be confirmed with the aid of speculum examination or with an ultrasound scan. On diagnosis is made, your doctor will counsel you on prompt evacuation of the uterus to prevent further blood loss. Blood loss may be excessive where products of conception distend the uterus and may cause shock.
- Incomplete miscarriage: this is an extension of inevitable miscarriage used to describe a state that products of conception are still retained in the uterus. The cervical os is open; bleeding is severe because of retained products. Severe bleeding often results in shock requiring emergency treatment.
- Complete miscarriage: in this state, there is complete passage of the product of conception. There is cessation of vaginal bleeding and abdominal cramps resolves. Diagnosis is confirmed with the aid of an ultrasound scan which will reveal an empty uterus.
- Septic miscarriage is a variety of miscarriage caused by the infection of the products of conception. It can arise from inevitable or incomplete abortion. Patients may develop symptoms like fever, severe abdominal pain, and purulent vaginal discharge. This is a serious complication that can lead to septic shock and peritonitis.
There are many causes of miscarriage but no one can foretell in any particular pregnant woman what the outcome of her pregnancy will be. Majority of women who have suffered miscarriage go on to have perfectly normal pregnancies and babies. Consult your physician if you are suffering from habitual miscarriages.