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POTENTIAL CAUSES OF RECURRENT MISCARRIAGE
POTENTIAL CAUSES OF RECURRENT MISCARRIAGE
Introduction
Experiencing a miscarriage can be a heartbreaking and emotional experience for many women. Unfortunately, some women may go on to experience recurrent miscarriages, which can be devastating and leave them feeling hopeless. Recurrent miscarriage is defined as the loss of three or more consecutive pregnancies before 20 weeks gestation. While it's estimated that about 1% of women will experience recurrent miscarriage, the underlying causes of these losses can be complex and varied. In this article, we'll explore some of the most common causes of recurrent miscarriage and what steps women can take to increase their chances of a successful pregnancy.
Lifestyle Factors
We are all familiar with the hazards associated with tobacco, alcohol, and illicit drugs. They are not only detrimental to our general well-being but can also pose serious risks during conception and pregnancy. Smoking during pregnancy can lead to vaginal bleeding and a greater chance of miscarriage. Similarly, women who indulge in excessive alcohol consumption or drug use are at a considerably higher risk of suffering a miscarriage. If you are involved in such activities, particularly during pregnancy, it is vital to discontinue them immediately. Although quitting may not be easy, seeking advice from your healthcare provider can help you find a suitable program that is tailored to address your specific concerns.
Chromosomal Problems
The leading cause of miscarriage, as per medical experts, is believed to be chromosomal abnormalities in the fetus. Chromosomes are structures found within the cells of the body that contain genes determining an individual's characteristics. During conception, when the egg and sperm unite, several complex and intricate steps need to occur with absolute precision for the formation of a healthy fetus. However, accidents and mistakes can happen, resulting in an abnormal fetus. The majority of these abnormalities are severe and incompatible with life, resulting in nature's way of ending the pregnancy. Although the risk of chromosomal problems increases with age, they are usually an accidental occurrence of that particular pregnancy and not likely to happen again in a later pregnancy. In some rare cases, less than 5 percent, the problem is inherited, causing recurrent miscarriage until the parents receive the appropriate diagnosis and treatment. These parents may have no visible physical or mental disabilities but possess balanced, abnormally arranged chromosomes that can result in miscarriage. Genetic tests are available to diagnose this rare condition, making it essential to receive genetic counselling following recurrent miscarriages.
Low Progesterone Level
The precise link between hormonal imbalances and miscarriages remains uncertain. However, many medical professionals believe that a lack of progesterone in the early stages of pregnancy can increase the likelihood of miscarriage. Understanding the role of progesterone is crucial in this context. After ovulation, the corpus luteum, which was originally a follicle, starts producing progesterone. In the event of pregnancy, the corpus luteum functions as a temporary source of progesterone, which thickens the uterus lining to sustain and nurture the fertilized egg. If progesterone levels are too low, the fertilized egg may not implant properly, or the pregnancy may not receive adequate support, leading to bleeding and miscarriage. The causes of low progesterone levels are unknown, but it is believed that around 15 percent of women with fertility issues may experience this problem. A simple blood test can diagnose insufficient progesterone levels, and supplementation is usually prescribed in the form of suppositories or injections from the time of a positive pregnancy test until around the 13th week of pregnancy. By this stage, the fetus and placenta can usually generate sufficient progesterone on their own to maintain the pregnancy.
Abnormalities of the Uterus
If you experience recurrent miscarriage, it could be due to abnormal anatomy in your uterus or cervix. Research indicates that this condition affects approximately one in 700 women. If you have an abnormal uterus or cervix, it may have developed during your fetal development, and you might not have been aware of it until you tried to conceive. However, having an abnormal uterus or cervix does not necessarily mean that you cannot have children, but it may increase the risk of miscarriage. Certain issues, such as a septate uterus, uterine fibroids, an incompetent cervix, and endometrial polyps, have been linked to recurrent miscarriage.
A septate uterus is a rare abnormality that occurs when your uterus is divided into two sections by a wall of tissue, resulting in abnormally shaped and smaller uterine cavities that are less capable of carrying a full-term pregnancy. As a result, miscarriages and preterm births are more likely. Uterine fibroids are another potential structural issue of the uterus. These are benign muscular bulges of tissue that grow within the uterine wall. Although it is possible to have uterine fibroids and experience a completely normal pregnancy, these growths sometimes make it difficult for the egg to securely implant itself in the uterine lining, resulting in an early miscarriage. Uterine fibroids typically run in families. An incompetent cervix is a condition in which the cervix widens and opens too soon, leading to pregnancy loss. It typically results in a later pregnancy loss, usually during the second trimester, when the pregnancy has grown enough, and the weight is too much for the weakened cervix to hold. Incompetent cervix could be a condition that you were born with, but most likely it is the consequence of a past surgery to your cervix. Endometrial polyps are (usually benign) growths of fleshy tissue that protrude from the lining inside of your uterus. They may cause no symptoms. However, some women experience abnormal bleeding. If they become large or if multiple polyps exist, they may interfere with your ability to conceive or increase your risk of miscarriage.
Sometimes, abnormalities of the uterus and cervix are detected before pregnancy. Unfortunately, they are often discovered during an evaluation after you have suffered recurrent miscarriages. If your doctor suspects an abnormal anatomy of your uterus, you will most likely undergo a hysterosalpingogram (HSG) for diagnosis. This is an x-ray test that involves injecting a dye into the uterus through the vagina. Your reproductive tract will be highlighted on the x-ray, and a diagnosis can usually be made. Diagnosing an incompetent cervix is more difficult. Usually, a prior history of second-trimester pregnancy loss is required.
In many cases, these abnormalities can be treated with surgery. For a septate uterus, doctors often recommend surgery to unite the two sections of the uterus, resulting in a larger uterine cavity that gives the upcoming pregnancy more room to grow. However, this is a complicated surgery that carries risks such as hemorrhage and, in extreme cases, requires a hysterectomy. Uterine fibroids that are bulging into the uterine cavity can often be removed during an outpatient surgery. This is typically a straightforward surgery, but as with all surgeries, the woman faces potential risks. If you have an incompetent cervix, your doctor may recommend a cerclage procedure to strengthen your cervix and prevent dilation. A cerclage is a tough band of suture sewn around the cervix, like a purse string, to hold the cervical tissue tightly together. This procedure is usually performed at about 12 weeks of pregnancy, after a live fetus has been confirmed on ultrasound.
Medical Conditions
Certain medical conditions may increase the likelihood of experiencing a miscarriage. If these conditions are not properly monitored and controlled with medication, it may result in early pregnancy loss. Some of these medical conditions include
- Pelvic infection
- Diabetes
- Insulin resistance syndrome
- Thyroid disease
- Thrombophilia
- Lupus
- Antiphospholipid syndrome
It is recommended that individuals with these conditions work closely with their doctor to ensure their condition is well-controlled before attempting to conceive. In some cases, individuals may not be aware of their medical condition until after becoming pregnant, and it is advised to consult with a disease specialist to increase the chances of a successful and healthy pregnancy.
Diagnosing the cause of recurrent miscarriages
Before a thorough evaluation is performed, you may have already experienced one or more miscarriages. It's crucial to work closely with your doctor to determine the reason for your recurrent miscarriages. Discuss your medical history, previous pregnancy experiences, and any medical conditions or risk factors with your doctor. A complete physical examination and numerous diagnostic tests will likely be ordered to determine the cause of your miscarriages. Below is a list of potential tests and studies you may need to undergo:
Blood tests: Your blood will be analyzed for progesterone levels, certain viruses, diabetes, thyroid function, blood-clotting disorders, and other immune disorders.
Pelvic infection testing: Your vagina and uterus may be swabbed, and the swabs sent to the laboratory for infection testing.
Genetic evaluation: The miscarriage tissue, you, and your partner may be tested for the presence of abnormal chromosomes.
Ultrasound: Ultrasonic sound waves create an image of your pelvis on a monitor, and your pelvic anatomy can be evaluated for possible issues.
Sonohysterogram: Sterile water is injected into the uterus in this specific type of ultrasound to better view and evaluate potential abnormalities.
Hysterosalpingography: This is a special type of x-ray called fluoroscopy of the uterus and fallopian tubes performed after injection with dye. It helps detect some problems within the uterus and pelvic anatomy. However, HSG is best suited to determine the openness of the fallopian tubes.
Hysteroscopy: A narrow, telescope-like device is inserted into the uterus to view the inside and check for abnormalities.
Remember that even if no underlying cause is found, many women go on to have successful pregnancies. Treatment options are available if you and your doctor do find an underlying cause so that you can hopefully enjoy future successful pregnancies.
Conclusion
In conclusion, recurrent miscarriages can be a devastating experience for couples hoping to start a family. However, with proper medical attention and evaluation, the underlying causes can often be identified and treated. From hormonal imbalances to genetic abnormalities, there are many factors that can contribute to recurrent pregnancy loss. If you have experienced multiple miscarriages, don't lose hope. Work closely with your doctor to determine the cause and explore treatment options. With the right care and support, many women are able to go on to have successful, healthy pregnancies. Remember, you are not alone in this journey, and there is always hope for a happy and healthy future.
Links and reference
Warhus, S.P. (2007) Fertility demystified. New York: McGraw-Hill.
