What is recurrent pregnancy loss (RPL)?
If a woman has 2 or more miscarriages before her pregnancy reaches 20 weeks, she is said to have recurrent pregnancy loss (RPL). However, only clinical pregnancy losses are taken into consideration. A clinical pregnancy is one which can be visualized by an ultrasound. This is usually possible in 5-6 weeks of gestation or 1-2 weeks after a missed menstrual period. Pregnancies detected earlier than that through blood or urine tests, called biochemical pregnancies, are not counted when determining recurrent pregnancy loss.
What causes RPL?
The reasons for recurrent pregnancy loss include:
Genetic: Genetic abnormalities such as an extra or missing chromosome can occur in the embryo or fetus. Sixty percent of miscarriages in the first trimester are due to chromosome abnormalities. Genetic abnormalities make it difficult for the fetus to grow healthy. Women younger than 35 have a 10%-15% chance of having a miscarriage due to a chromosome abnormality. For women over 40, this is increased to 50%.
Anatomic: Pregnancy loss can be attributed to an abnormal shape of the uterus. This may be heredity or due to exposure to certain medications such as diethylstilbestrol (DES). Some women are born with a band of tissue called a septum within the uterus that can interfere with pregnancy. Other anatomic causes of recurrent pregnancy loss include fibroids and tumors growing within the uterine cavity.
Environmental/Habits: Smoking, alcohol, recreational drugs such as cocaine and excessive caffeine have been associated with pregnancy loss. Being overweight can also increase your risk of miscarriage.
Health conditions: Uncontrolled diabetes or thyroid disease as well as clotting disorders and immune disorders have been linked with pregnancy loss.
Unknown: The cause cannot be identified 50% of the time but unknown genetic abnormalities are suspected.
Are there any tests to see why I have RPL?
Blood tests can identify health conditions such as diabetes or thyroid disease which may be responsible for pregnancy loss. A special blood test called a karyotype can be used to study the genes of the parents. Imaging studies such as sonohysterogram or hysterosalpingogram can be performed to evaluate the shape of the uterus. Tissue from a miscarriage can be examined in the laboratory for genetic abnormalities.
How is RPL treated?
A medical or surgical cause, if treatable can reduce the risk of future pregnancy loss. Your doctor may suggest:
Surgery: Surgery may be performed to correct the shape of the uterus or remove abnormal tissue such as a septum, scar tissue, fibroid or tumor. Surgery is performed through a tube called a hysteroscope which is inserted through the vagina to reach the uterus.
Anti-clotting medication: Women with clotting disorders or certain autoimmune conditions can take medications such as heparin or aspirin to reduce the risk of miscarriage. This however carries certain risks and needs to be carefully monitored by your doctor.
Addressing medical issues: Medical conditions such as diabetes, thyroid disease or high prolactin levels may be treated reducing your risk of pregnancy loss.
Identifying genetic disorders: Genetic issues can be identified by appropriate screening of both partners. In 5% of couples, one of the parents has an abnormal arrangement of chromosomes that increases the risk of miscarriage. If a problem is identified, your doctor may suggest in vitro fertilization where eggs and sperm are united in a laboratory and the resultant embryos are genetically tested before implanting it in the uterus.
Change in lifestyle: Staying healthy, losing weight (if you are overweight), avoiding smoking and recreational drugs, and limiting the use of alcohol and caffeine can improve your chances of having a healthy pregnancy. RPL can result in mental strain and depression which may not be favorable for a future pregnancy. Your doctor can suggest appropriate therapy and counselling.
What are my chances of having a baby if I have RPL?
You have a 60%-80% chance of having a successful full-term pregnancy even after 3 miscarriages.