If you have had a miscarriage, chances are you want to know what caused it, and what you can do to prevent it from happening again. Most pregnancy losses result from chromosomal, or genetic, abnormalities, and are random events. The egg, the sperm, or the early embryo, either of it may be the cause of the abnormality. Very often, the symptoms of pregnancy go unnoticed by women. The risk of miscarriage increases with the number of previous pregnancy losses, but is typically less than 50%.
Most couples with recurrent pregnancy loss have several risk factors for miscarriage, and an extensive analysis is required for all major factors.
Most miscarriages occur randomly when an embryo receives an abnormal number of chromosomes during fertilization. This is a genetic problem; there are medical condition that causes it. However, it becomes more common in women with increased reproductive age.
Recurrent pregnancy loss (RPL), habitual abortion or recurrent miscarriage is defined as the failure of pregnancy before the fetus is 20 weeks old. Besides being a medical issue, it is also a serious disturbing psychological condition. This condition can make the woman depressed and tremendously drained of hope. However, it may be of some relief that most women who have experienced recurrent miscarriages go on to become happy mothers under medical supervision. A woman with a history of recurrent miscarriages has around 60% of chances to have a baby especially if there isn’t any explanation for the miscarriage. In about 50% of the cases, where it is difficult to determine the cause for miscarriage, pregnancy is still viable.
Uterine conditions: Uterine malformations contribute to around 15% cases of recurrent miscarriages. A septate uterus (uterus cavity divided by a long lump of tissues collectively termed as a septum) is the most common uterine abnormality. This condition is generally diagnosed by combined laparoscopy or MRI.
Cervical conditions: Cervical conditions such as cervical incompetence or weak cervix is the next common condition resulting in recurrent abortions. If not treated on time, this can lead to preterm deliveries or miscarriages.
Genetic disorders are also responsible for repetitive abortions. Here are a few genetic or chromosomal reasons:
Translocations: Robertsonian translocation in either of the partners can cause non-viable fetus and abortion. That is the reason why doctors prefer to carry out karyotyping for both the partners.
Aneuploidy: Aneuploidy is the presence of abnormal numbers of chromosomes in a cell. This chromosomal disorder occurs more frequently with increasing reproductive age and depicts germ cell quality.
Endocrine disorders: Endocrine factors contribute to 8-12 percent of recurrent pregnancy loss. Hypothyroidism can result in recurrent miscarriages or untimely loss of pregnancy. Undiagnosed and untreated diabetes mellitus can also cause miscarriages. Women affected with polycystic ovarian syndrome experience higher risk of untimely termination of pregnancy due to unsure dates.
Thrombophilia: Thrombophilia or tendency for blood clotting is another risk for miscarriages.
Immune factors: Lowered maternal immune tolerance for the fetus is another factor causing miscarriages.
Antiphospholipids syndrome: This is an autoimmune disease and accounts for 15% of all recurrent miscarriages. Doctors usually prescribe aspirin or heparin for women having antiphospholipid syndrome.
Thyroid antibodies: Anti-thyroid antibodies are also concerned with recurrent miscarriages.
Ovarian factors: With advancing age, the susceptibility to miscarriage increases as the ovarian reserves start depleting with increasing age and may lead to miscarriages. The actual cause is the poor quality of maternal eggs
Luteal phase defect: Ovaries release a hormone called Progesterone, around the time of ovulation. If the ovaries are unable to produce progesterone in sufficient quantities, pregnancy cannot sustain and may result in miscarriage.
Lifestyle factors: Excessive exposure to toxins, smoking or consuming alcohol can also cause recurrent miscarriages
Infections: Many infections such as toxoplasmosis, listeriosis and viral infections (rubella, measles, herpes, cytomegalovirus) etc. are also among the notorious causes of miscarriages
To find out the underlying cause of recurrent miscarriage, thorough clinical examination is now available at high-tech labs. Obstetricians do ultrasound scans to assess the condition of the uterus and ovaries. Both the partners have to undergo blood tests to rule out the presence of any chromosomal abnormalities. If the blood tests detect anything abnormal, doctors proceed with genetic counselling.
To find out any underlying viral or bacterial infection, we now have specialized tests like TORCH. Tissues from the placenta may also be tested for signs of a problem.
Sometimes, the tests do not yield any results. If there is no specific cause of miscarriages, chances are that you will get through your pregnancy the next time.
Treatment depends upon identification of the cause but unfortunately there is no actual treatment for unexplained recurrent pregnancies.
Abortion counselling is done with the primary objective to empower the woman. Do not force the decision and allow the couple to make their decision. Restrict rigorous activities and exercises. Intercourse is not advised while you are expecting particularly in the first trimester and third trimester. Some experts advise progesterone but it is a bit controversial. It relaxes smooth muscles .Progesterone should only be used if there is luteal phase defect or if your obstetrician is sure about the use.
In patients having anti-phospholipids syndrome (APS), heparin administration can increase birth rate up to 70 percent. According to some experts the administration of metformin in pregnancy can lower the risk of abortion especially in patients having polycystic ovarian syndrome
McDonald stitches or cervical cerclage (procedure in which stitches are used to close the cervix during pregnancy to help prevent pregnancy loss or premature birth) is done for cervical incompetence patients. The cerclage however poses a potential threat of inducing uterine contractions. The process is beneficial to women having cervix less than 25 mm
Unexplained miscarriages do carry a good chance of having a successful pregnancy in future. Though your pregnancy will be very closely monitored, yet it will be this close care that will boost your chances of having a healthy baby. Some causes of recurrent miscarriage are treatable, your obstetrician is the best person to answer you. There cannot be complete certainty in such cases, but you will be closely ascertained. If you have been emotionally drained because of repeated losses and are feeling low and scared to lose another baby, it would be wise to seek support and help from family, friends and support groups. Keeping a positive mind and an optimistic attitude can help you have a normal pregnancy.
Let us know how we can help.