Recurrent Pregnancy Loss: What You Need to Know
Date: July 1, 2007
At a recent appointment with a new physician, the nurse asked me how many times I had been pregnant. “Four,” I answered, surprised because it hadn’t been in the forefront of my mind in several years.
“And how many children do you have,” asked the nurse.
“Two.” I explained, “I had two miscarriages.”
Before my first son was born, I had a miscarriage at 11 weeks and one at 7 weeks. After the second one, I asked my OB-GYN to run some tests, but nothing abnormal turned up. The third time I got pregnant, I was given a progesterone supplement to try (there is anecdotal evidence this helps, but no research has proven it). I had a successful pregnancy, and a few years later — with no special treatment — another successful pregnancy.
Determining the cause of recurrent miscarriage is not easy, and for the majority, the reasons are unknown. But it is important for couples with recurrent miscarriage to research and talk with their doctors about all the possibilities — for their own peace of mind.
Defining Recurrent Miscarriage
Miscarriage is the loss of a pregnancy before 20 weeks, according to the American College of Obstetricians and Gynecologists (ACOG). Currently, the ACOG pamphlet Repeated Miscarriage defines recurrent miscarriage as pregnancy loss two or more times in a row. The classic definition, however, is three or more consecutive losses, according to Jennifer Greene, M.D., assistant professor with the all-female OB/GYN Group at Wake Forest University Baptist Medical Center.
“In most cases, investigation of recurrent pregnancy loss is offered to couples of reproductive age after three consecutive first or early second trimester losses,” Greene explains. “Older couples (fourth decade) with infertility and recurrent loss may warrant evaluation after only two losses because there is a decrease in the likelihood of successful pregnancy with increasing maternal age. Couples experiencing a mid to late second trimester loss are often evaluated for maternal anatomic abnormalities after only a single loss.”
Miscarriage is not uncommon. It is estimated that every woman has a 15 percent to 20 percent chance of having a clinically recognized pregnancy — one that has been confirmed by a pregnancy test or a missed period — end in miscarriage.
For women who have had one miscarriage, their chances of carrying the next pregnancy to full term remain about the same as if they had never had a miscarriage. After two miscarriages, a woman has a 30 percent chance of miscarrying again, according to the ACOG. After three miscarriages, the risk increases to 33 percent.
Once recurrent miscarriage is determined, discuss testing for causes of miscarriage thoroughly with your provider. “The clinical circumstances should be discussed to prevent an unwarranted battery of tests that may not contribute any useful information,” Greene says.
Causes of Repeated Miscarriage
Most of the time, the cause of a miscarriage cannot be found. “In cases of couples with recurrent pregnancy loss, the underlying cause is unknown in 50 percent to 75 percent of the cases,” Greene says.
Still, there are many known causes that can be investigated. “Fetal chromosome abnormality is the most common cause of early miscarriage,” Greene explains. There can be problems with the number or structure of chromosomes, or with the genes they carry, so the fetus will not grow as it should. These problems mostly occur by chance and have nothing to do with the health of the mother or father.
However, in some cases problems with the parents’ chromosomes can cause repeated losses, and reproductive technology has opened the door to new therapies for treatment. “Couples with chromosomal abnormalities such as balanced translocations or chromosome inversions can undergo pre-implantation genetic diagnosis as part of in-vitro fertilization,” Greene says. “The embryos undergo biopsy and karyotyping, which permits the selection of chromosomally normal embryos for intrauterine placement and attempted gestation, thus greatly improving the likelihood of successful pregnancy in a couple that would otherwise have little available therapy.”
Problems of the uterus, such as a cervix that begins to widen and open too soon in the middle of pregnancy, or fibroids, are linked to recurrent miscarriage and can be treated with surgery.
Medical conditions in the mother that have been linked to repeated pregnancy losses include immunological conditions such as lupus and antiphospholipid syndrome, a condition in which women are at increased risk for blood clots and pregnancy loss. Women with the condition have antiphospholipid antibodies (cardiolipin or lupus anticoagulant antibodies) in the blood that are detectable with testing. With this condition, some women take low-dose aspirin and heparin to increase blood flow to the placenta and inhibit the tendency to clot. For immunological problems, “therapies include plasmapheresis, progesterone and IVIG (a treatment for antibodies),” Greene says, “ but these therapies remain experimental and controversial.”
Other medical conditions that have been linked to pregnancy loss include heart disease, severe kidney disease, diabetes, thyroid disease, infection in the uterus such as mycoplasma or ureaplasma, polycystic ovary syndrome, hormone imbalance and certain blood disorders such as thrombophilia, which makes blood clot more than it should.
Tests to Discuss with Your Doctor
If you have had repeated miscarriages, talk to your physician about pursuing the cause. “The initial steps in the evaluation involve a detailed history, including family history, and a complete physical examination including a pelvic examination,” Greene says.
In addition, you and your physician might consider the following tests.
• Blood tests to find any problems with hormones or the immune system. “Maternal screening for thyroid disease, diabetes and diseases that indicate a predisposition to clotting, such as antiphospholipid syndrome and thrombophilias, should be performed,” Greene says.
• Chromosomal testing of you and your partner or of the miscarriage tissue.
• Tests to detect infection of the uterus.
Your physician may also recommend procedures to detect problems in the uterus.
• Hysterosalpingography is an X-ray of the uterus and fallopian tubes that is taken after the organs are injected with a small amount of dye.
• Hysteroscopy is a device that is inserted through the vagina and cervix to view the inside of the uterus.
• With an ultrasound, sound waves are used to create an image of the internal organs.
• A sonohysterogram is a vaginal ultrasound that is used to view the uterus.
The cause of miscarriage cannot always be determined, but better testing and innovative treatments are giving couples with recurrent miscarriage more hope. And even if a cause is not determined, there is still a good chance for success. “The likelihood of a normal pregnancy after one or even numerous pregnancy losses,” Greene says, “is greater than the likelihood of a subsequent loss.”
Losing a baby through miscarriage is painful, and many couples find support helps them get through a very trying time. Heartstrings Infant Loss Support Group offers group support, one-on-one support for those with similar losses through its Connections program, and online support. All programs are available for anyone who has lost a baby from conception to 1 year of age.
For more information, visit www.heartstringsgso.org or call (336) 335-9931.