What is Recurrent Miscarriage
Recurrent miscarriage happens when a woman has more than two clinical pregnancy losses (miscarriages).
The American College of Obstetricians and Gynecologists (ACOG) recommends a physical exam and testing after three miscarriages.
But the Women and Infants Fertility Center recommends the evaluation after two miscarriages.
Two-thirds of women having recurrent miscarriages eventually carry a full-term healthy pregnancy, without any treatment.
What does recurrent miscarriage mean?
Recurrent miscarriage known as habitual abortion or recurrent pregnancy loss that happens when a woman has more than two clinical pregnancy losses. Doctors would define a clinical pregnancy as one having clinical evidence of the pregnancy like visual or laboratory indications of the gestational sac (the cavity of fluid surrounds the embryo), fetal pole or the placenta (thickens on the margin of the yolk sac of a fetus) of an early ultrasound.
Clinical pregnancies usually differ from chemical pregnancies in which a miscarriage occurs before there is any evidence of the pregnancy besides a positive pregnancy or the blood test. Among all clinical pregnancies, 15 to 20 percent usually end up in miscarriages.
Based on ACOG, 5 percent of women have more than two consecutive miscarriages and 1 percent of women experience three or more. The risk of recurrent miscarriage is higher in women above the age of 35 or women who had previous miscarriages.
Most women have miscarriages before they knew they were pregnant and do not experience any symptoms or signs of the miscarriage. The healthcare provider detect and diagnose a miscarriage by using the ultrasound (the diagnostic imaging technique using sound waves).
The majority of miscarriages happen due to genetic abnormalities in the fetus or like an extra chromosome or missing chromosomes. The typically random mutations are not likely to recur. The recurrent miscarriage has different situation and doctor look for the specific type of mutation known as the balanced translocation. When associated with recurrent miscarriage, it still remains an uncommon occurrence.
Few women who had a miscarriage or recurrent miscarriages may experience vaginal bleeding, fullness in the breasts, loss of tenderness and loss of sound or fetal movement.
Women must report such signs to their doctor to keep track of their bleeding.
When a patient pass a tissue during a miscarriage, it should be saved. The doctor can further use it to determine the cause of the miscarriage.
A miscarriage cause feelings of loss and sorrow. Few doctors recommend the patients to join a support group and talk about the experience and grief associated with the loss of the pregnancy.
Women carry limited number of eggs and with the progressing reproductive years, the eggs lacks in quality and number. This decreases the chances of having baby by 3%-5% after the age of 30. The reduction in fertility is found to extend after the age of 40.
What leads to recurrent miscarriage?
The genetic abnormalities
The genetic abnormality happens when an embryo (fertilized egg) receives an abnormal number of chromosomes on the fertilization. This type of genetic cause happens by chance and there seems no medical condition for it. In a few couples who experienced recurrent miscarriages, one partner could have chromosome translocation (one piece of a chromosome breaks and attaches to a second chromosome).
The anatomic abnormalities
The septate uterus where a wall of tissue divides the uterus into two sections happens very commonly that result in recurrent miscarriage. It is still not clear why this leads to recurrent miscarriage, few health providers believe poor vascularity of the septum causes the embryo to stop growing when it gets implants there. When the pregnancy makes it to term, the fetus might be breech. Removing a uterine septum is easy to do surgically.
The incompetent cervix cannot remain closed due to weakened muscles. When the developing fetus reaches a certain weight the weakened cervix cannot support the fetus and could result in miscarriage.
Several medical conditions
Several types of medical conditions increase the risk of recurrent miscarriage like:
The Antiphospholipid Syndrome (APS) – This autoimmune disorder occurs when a person’s immune system makes antibodies to certain substances by mistake that is needed for blood clotting.
Hormonal issues or Thyroid – The overactive or underactive thyroid (the endocrine gland present at the base of the neck) result in hormonal imbalances. Hormonal imbalances cause miscarriage when the uterine lining doesn’t normally develop for implantation and nourishment of a fertilized egg. Higher levels of prolactin (the reproductive hormone of the pituitary gland) alter the proper development of the uterine lining.
Polyps and Fibroids – Non- cancerous growths invade the uterus.
The Asherman’s syndrome – A condition where scar tissue forms inside the uterus and result in miscarriage.
To diagnose recurrent miscarriage
To understand the cause of recurrent miscarriages, a fertility specialist would review the patient’s medical history and past pregnancies. The doctor recommends a complete physical exam like the pelvic exam.
When recurrent miscarriages are suspected to be the result of a genetic error, the doctor performs a karyotype, a test to identify and evaluate the size, shape and number of chromosomes.
When a doctor suspects the reason for recurrent miscarriage is due to a uterine problem, they perform imaging tests like a sonogram, MRI or an ultrasound.
The hysterosalpingogram (HSG) (X-ray of the fallopian tubes and the uterine cavity) or an ultrasound shows that a woman has problems with the shape of her uterus. The physician conducts blood tests to detect problems with the immune system like the APS.
Almost 50 percent of women evaluated for recurrent miscarriage have a clear diagnosis. While the remaining patients do not have a reason for their recurrent miscarriage diagnosis.
The group of women not knowing the cause of their diagnosis have the chance of a successful outcome as high as 70 percent based on the maternal age of the patient.
