Miscarriages often called spontaneous abortion by doctors, is the loss of a pregnancy before 20 weeks. It occurs in about 15-20% of all pregnancies. Most happen in the first 3 months. Many miscarriages take place before a woman even knows that she is pregnant.
Three or more miscarriages in a row may be called repeated miscarriage (or habitual abortion). Women who have had repeated miscarriages need special tests to try to find the reason for them.
After several miscarriages, you may wonder whether you will ever be able to have a healthy baby. Be hopeful. The chances of having a successful pregnancy are good even after more than one miscarriage. This pamphlet will help you understand the reasons for repeated miscarriage and what can be done to prevent future ones.
It will address the following questions:
- What causes repeated miscarriage?
- What tests and procedures might my doctor suggest?
- If I become pregnant again, what special care will I need?
- What can I do to increase my chances of having a successful pregnancy?
- How can my partner and I cope?
Often, the reason for repeated miscarriage is not known. Sometimes, however, it has a definite cause. Examples of known causes include:
- Chromosomal problems
- Illnesses in the mother
- Hormone imbalance
- Disorders of the immune system
- Abnormalities of the uterus
- Environmental and lifestyle factors
If you have had more than one miscarriage, each may have had a different cause.
Over half of miscarriages in the first 13 weeks of pregnancy are caused by problems with the fetus’s chromosomes. Chromosomes are tiny structures inside the cells of the body. Each carries many genes, the basic units of heredity. Genes determine all of a person’s physical makeup, such as sex, hair and eye colour, and blood type.
Problems with the number or structure of chromosomes, or with the genes they carry, can lead to miscarriage. Often this is nature’s way of ending a pregnancy in which the fetus was not growing normally and would not have been able to live.
Most chromosomal problems happen by chance. They have nothing to do with the mother’s or father’s health. They are not likely to occur again in a later pregnancy. However, in a small number of cases, problems with the parents’ chromosomes can cause repeated miscarriage. There are tests to determine whether chromosomal problems are a factor in repeated miscarriage.
Illnesses in the Mother
Certain illnesses in the mother have been linked to a greater risk of repeated miscarriage:
- Systemic lupus erythematosus and other autoimmune disorders
- Congenital heart disease
- Severe kidney disease, especially when linked to high blood pressure (hypertension)
- Diabetes that is not controlled
- Thyroid disease
- Intrauterine infection
Treatment of some of these illnesses can improve the chances for a successful pregnancy. This is especially true if they were under control before a woman became pregnant. Other illnesses may need special care or monitoring during pregnancy.
Progesterone is a hormone that prepares the lining of the uterus during the second half of the menstrual cycle to nourish a fertilized egg. If the egg is not fertilized, it is shed with the uterine lining during the menstrual period. If the egg is fertilized, hormones continue to prepare the uterus for pregnancy. Early in pregnancy, it is important that enough progesterone is made to maintain the pregnancy. Otherwise, miscarriage will occur. If tests show that a woman’s body is not making enough progesterone, her doctor may prescribe supplements to correct the problem.
Disorders of the Immune System
The immune system is designed to recognize and attack foreign substances within the body. Antibodies are formed to help the body fight off disease and heal itself in case of infection. Normally, the mother’s body protects the “foreign” fetus from attack by her own antibodies. It is thought that this protection may be absent in the blood of some women who have had a repeated miscarriage.
Other immune system problems are caused by differences between the mother and the fetus and even between the mother and the father. For instance, the mother’s own immune system may produce antibodies to the cells of her own body. This can cause pregnancy loss. Tests may show some problems with the immune system.
Abnormalities of the Uterus
Several abnormalities of the uterus, most of which can be treated with surgery, are linked to repeated miscarriage:
Congenital abnormalities: These are defects present from birth. For example, a woman may have a uterus that is divided into two sections by a wall of tissue (septate uterus).
Uterine fibroids (leiomyomata): Uterine fibroids are benign growths (not calker) made up of uterine muscle tissue.
Incompetent cervix: An incompetent cervix is one that begins to widen and open too early, in the middle of pregnancy, without any sign of pain or labour.
Environmental and Life Style Factors
Pregnant women who smoke also have a greater risk of miscarriage than those who do not smoke. Heavy use of alcohol and use of illegal drugs, especially cocaine, may also increase the risks. It is possible that exposure to high levels of radiation or toxic substances may be a factor in repeated miscarriage.
Because repeated miscarriage has many possible causes, your doctor will need a great deal of information to diagnose the problem. You will be asked about your medical history and past pregnancies, as well as your lifestyle and work setting. A complete physical exam, including a pelvic exam, is also important.
Your doctor may also suggest some or all of these tests:
- Blood tests for possible problems with hormones or the immune system
- Chromosomal testing of both you and your partner
- Genital tract cultures for the presence of infection
- Chromosomal testing of tissue from the miscarriage, if available
Procedures that might also be done include:
Endometrial biopsy: In this procedure, a sample of the tissue that lines the uterus is taken and looked at under a microscope.
Hysterosalpingography: This is an X-ray of the uterus and fallopian tubes. It is taken after the organs are injected with a small amount of fluid.
Hysteroscopy: In this procedure, the doctor inserts a hysteroscope—a thin, telescope-like instrument—through the vagina and cervix to view the inside of
the uterus. Hysteroscopy is minor surgery that can be done with general, local, or in some cases, little or no anaesthesia.
Laparoscopy: This is a surgical procedure in which a slender, light-transmitting instrument, the laparoscope, is used to view the pelvic organs.
Ultrasound: In this procedure, sound waves are used to examine the fetus or view the internal organs.
Special Care for Future Pregnancies
Sometimes the problem that caused the miscarriages can be treated. Surgery may be effective for some problems of the uterus and cervix. Treatment with antibiotics can cure infections. Hormone treatment may help in some cases.
If chromosomal problems are found in the parents, your doctor may advise genetic counselling. A genetic counsellor can help you and your partner understand what risks a genetic problem might pose for future pregnancies. The fetus can be tested for some problems in future pregnancies by amniocentesis or chorionic villus sampling.
What You Can Do
If you have had a repeated miscarriage, future pregnancies should be planned, diagnosed early, and watched carefully. You can improve your chances of having a successful pregnancy in the future by doing the following things:
- Have a complete medical workup before you try to get pregnant again. It may be that the cause of the miscarriages can be found and treated by your doctor.
- If you think that you might be pregnant, see your doctor right away. The sooner you seek prenatal care, the sooner you can receive any special care that you may need.
- Follow your doctor’s instructions. He or she will tell you what you need to do to keep yourself and your fetus as healthy as possible.
Coping with Repeated Miscarriage
- The loss of a pregnancy—no matter how early or how late—can result in feelings of grief. You may be troubled and even overwhelmed by grief and discouragement. For many women, the emotional healing takes longer than the physical healing that follows a miscarriage.
- Grief can cause you to blame yourself although you did nothing wrong. You might find yourself thinking about the early days of your pregnancy, searching for a clue that would explain the loss. You may also find yourself angry at your partner or other loved ones for no good reason. Other signs of emotional stress might include headaches, loss of appetite, sleeplessness, fatigue, and trouble concentrating.
- Your feelings of grief may be different from those of your partner. You are the one who felt the physical changes of pregnancy. Your partner may also grieve, but he may not express his feelings as directly as you do. He may feel that he has to be strong for both of you and may be reluctant to share his hurt and disappointment. This may create tensions between the two of you just when you need each other the most.
- Emotional pain is as real as physical pain, even though the injury cannot be seen or touched. If you feel sad, allow yourself to grieve. Grieving will help you accept the loss and get on with your life.
- Above all, don’t blame yourself for the miscarriages. Self-blame is self-punishment, and you do not deserve punishment. On the contrary, you need and deserve love, support, and reassurance.
- Reach out to those closest to you and ask for their comfort and support. Talk to your doctor. There may be support groups in your area that are eager to help. Counseling can help both you and your partner if you think that you can’t deal with your feelings alone.
Finally . .
Even if you have had repeated miscarriages, you still have a good chance to have a successful pregnancy. This is true even if the cause of the past pregnancy losses cannot be found.
Future pregnancies will need prompt, early evaluation. Your doctor will check your pregnancy closely and provide any special care you may need as your fetus grows.
If you need advice regarding repeated miscarriages, please feel free to schedule an appointment to see Dr. Gan.
— Dr.Gan Kam Ling
Consultant Obstetrician And Gynaecology