The majority of women who miscarry have a successful pregnancy subsequently.
MISCARRIAGE is the loss of an embryo or a foetus before 24 weeks of pregnancy. Many miscarriages occur before a missed period or before the pregnancy is confirmed.
The likelihood of a miscarriage in the first three months of pregnancy is about one in four to five confirmed pregnancies. Most miscarriages are sporadic events.
There is much that is not known about the causes of miscarriages, partly because it is not investigated until there are recurrent miscarriages. The majority of early miscarriages is believed to be due to chromosome problems – either a lack of or too many.
There are several factors that increase the risks of miscarriage: age (the risk of miscarriage at age 30 years is one in five and at age 42, one in two); uterine abnormalities; infections; medical problems, likely poorly controlled diabetes; smoking; and excessive alcohol consumption. There is no evidence to show that stress, sex, exercise or lack of rest increases the risk of miscarriage.
A miscarriage may be complete or incomplete. In the former, bleeding usually stops after seven to 10 days. In the former, bleeding continues and there may be an infection.
When a pregnancy is lost, the patient, her spouse and family can be affected. Some may experience symptoms like poor appetite, difficulty concentrating and difficulty sleeping. Some do not feel it initially but experience symptoms later. The spouses may also experience similar symptoms.
Some pregnant women do not have any symptoms. The miscarriage is discovered on routine antenatal ultrasound examination. This type of miscarriage is called a missed miscarriage. The most common symptom of a miscarriage is vaginal bleeding, which varies from spotting to the passing of clots. Whenever there is bleeding in pregnancy, medical attention should be sought. If it is heavy, there should be no delay in consulting a doctor.
Vaginal bleeding during pregnancy may be due to a threatened miscarriage. It must be remembered that many women have a successful pregnancy after a threatened miscarriage. Another common symptom is lower abdominal pain or backache, just like period pains. There may also be abdominal pain if there is infection, with or without fever and increased heart rate.
When a miscarriage has started, it cannot be stopped. An ultrasound will confirm that the pregnancy is ongoing or a miscarriage has occurred.
Medical attention should be sought if there is: concern about the amount of bleeding; pain that cannot be relieved by medicine; a smelly vaginal discharge; shivering; flu-like symptoms; fainting; and pain in the shoulders.
If the miscarriage is complete, no treatment is required. If the miscarriage is incomplete, the doctor will discuss treatment methods:
· Expectant management – This means doing nothing, that is, letting nature take its course. It is successful in 50 of 100 cases. It can take some time before there is bleeding, which may continue for up to three weeks. There may be abdominal cramps.
· Medical treatment – Tablets or vaginal pessaries may be prescribed to get the entrance of the uterus (cervix) to open up and allow the passage of the products of conception. This usually takes a few hours. There may be some abdominal cramps and bleeding or even passing of clots. The bleeding may last up to three weeks. The treatment is successful in 85 of 100 cases.
· Surgical treatment – This is advised when the bleeding is heavy and does not stop and/or there is infection. The operation, called an evacuation (emptying) of the uterus (using a suction device), is carried out under general or local anaesthesia. It is successful in more than 95 out of 100 cases. Complications are uncommon. They include heavy bleeding, infection and rarely uterine perforation, which will need repair.
Fertility is usually restored in the first month after a miscarriage. The best time to try again for another pregnancy is when you and your spouse are ready.
If another pregnancy is being planned, it is advisable to take 400mg of folic acid daily when you first start trying until 12 weeks of pregnancy, as this reduces the risk of neural tube defect (spina bifida) in the foetus.
When miscarriages occur three or more times in succession, it is called recurrent miscarriage. It occurs in about one in 100 women. There is a cause for the condition in some women but in many others, the causes cannot be confirmed.
More research is needed to elucidate the risk factors of recurrent miscarriages which include age and previous pregnancies, genetic factors, autoimmune factors, uterine abnormalities, cervical incompetence, infections, as well as diabetes and thyroid disorders.
The management of recurrent miscarriage is challenging for obstetrician and patient. The various methods include:
· Supportive antenatal care – Women who have supportive care from early pregnancy have a better chance of a successful birth. There is evidence that attendance at an early pregnancy clinic can reduce the risk of further miscarriages.
· Screening for genetic problems – A test for chromosome abnormalities, called karyotyping, may be carried out. If either you or your spouse has an abnormality, a referral will be made to a clinical geneticist, for genetic counselling.
· Screening for uterine abnormalities – This is done with pelvic ultrasound and if found, treatment will be considered.
Hysterosalpingography, which is an x-ray of the fallopian tubes and the uterine cavity with fluid injected through the cervix, is used in some hospitals. It has no advantages over ultrasound and may cause some discomfort.
· Screening for foetal abnormalities – If there is a miscarriage or stillbirth in the next pregnancy after a recurrent miscarriage, the embryo and placenta may be examined for abnormalities by karyotyping and microscopic examination. These tests may help the doctors in formulating possible choices and treatment.
· Screening for infection – If there is a history of miscarriages in the fourth to sixth month of pregnancy or pre-term labour, tests for bacterial vaginosis will be carried out and treatment instituted, if necessary.
· Treatment for aPL antibodies – There is evidence that if there are aPL antibodies and a history of recurrent miscarriages, low-dose aspirin and low-dose heparin in early pregnancy may improve the chances of a live birth up to about seven in 10, compared to about four in 10 if only aspirin is taken and one in 10 without treatment.
· Tests and treatment for cervical incompetence – If there is cervical incompetence, a vaginal ultrasound scan in pregnancy may provide an indication about the likelihood of miscarriage. An operation to insert a stitch in the cervix is made after the third month of pregnancy, to ensure it stays closed, may be carried out. This is usually done through the vagina.
Although the risk of giving birth early is decreased slightly, it has not been proven to improve the chances of the baby’s survival. The risks and benefits will be discussed with you.
· Hormone treatment – Progesterone or human chorionic gonadotrophin hormones have been prescribed in early pregnancy to prevent miscarriage. There is, however, insufficient evidence that it works.
It will not be possible to say for sure what will happen if there is another pregnancy in a person who has recurrent miscarriage. Even if a reason for the miscarriages cannot be found, the likelihood of a healthy birth is still three out of four.
Source: Dr Milton Lum