“Depending on how you define recurrent miscarriage,” says Dr. Jeff McKeeby, “I would estimate that at least three percent of couples are going through this experience. Because we’re following our patients from such an early point in their pregnancy, it’s likely that we see a greater percentage of miscarriage than in the general population.”
Until recently, miscarriage was referred to as “recurrent” if a woman experienced pregnancy loss three times or more. Now, partly due to advanced knowledge among reproductive medicine practitioners, women are typically advised to be seen for recurrent miscarriage (sometimes also called recurrent pregnancy loss, or RPL) after only two such events.
The term “miscarriage” is generally used to describe loss of a pregnancy up to 20 weeks gestation, most often in the initial 12 weeks or first trimester. Such spontaneous losses usually occur either because the embryo or fetus is not developing normally and/or other processes, such as implantation of the pregnancy within the wall of the uterus, are going awry.
“About half the time, we don’t find anything wrong,” McKeeby says regarding the diagnosis of miscarriage causes.
Establishing a cause when possible
While more is known today about very early pregnancy and miscarriage, Dr. McKeeby says that the causes with which his patients present initially are somewhat dependent on the referring practice. “There are some that are generally accepted, and there are some things that people believe may be causes but are hard to prove,” he explains. The most agreed-upon causes of recurrent loss are :
- chromosomal abnormalities in the parents
- having a condition that puts the woman at risk for abnormal blood clotting, such as having anti-phospholipid antibodies
- anatomic abnormalities such as uterine malformations, for example, uterine septum
- cervical incompetence (a factor in miscarriages occurring in second trimester or later)
More debatable causes include:
- endocrine disorders, like polycystic ovarian syndrome or luteal phase deficiency
- autoimmune problems besides anti-phospholipid antibodies
- sperm quality problems
- infections
- stress and environmental factors
Maternal age should be considered in the list of potential causes simply because statistically, women in their 40’s and older are documented as a group as having more chances of miscarriage.
“Most miscarriages, regardless of whether they recur or not, are due to chromosomal abnormalities, and the vast majority of those are due to either random chance [in the embryonic development process] or advancing maternal age,” McKeeby states.
Hope in the Form of Treatment
So while the actual starting point, the cause, of any individual miscarriage, may be hard to determine in many cases, women who’ve experienced such loss can do more than simply shrug their shoulders and hope for the best the next time around.
“Many of these problems can indeed be treated either prior to or very early in subsequent pregnancies,” assures Dr. McKeeby.
For example, if testing on the woman has indicated a thrombophilia disorder — a condition related to blood clotting — injections of a drug called Lovenox (a low molecular-weight heparin, or blood thinner) could be started at the first signs of pregnancy. If an anatomical condition existed, surgical correction could be performed prior to getting pregnant again.
McKeeby says, though, that miscarriage is so common, it’s not irresponsible for a patient or her OB to wait until a second loss before seeking possible causes. It’s appropriate to avoid over-testing and possibly rendering false test results with resulting over-treatment.
“We recommend evaluation after a second miscarriage,” he says, “because after two losses, your chances of another miscarriage are about 25 percent. After three losses, the chance is 30 percent. So since we’re not talking about a significant difference between those numbers, it makes sense to go ahead and start looking for things that may be correctable before a subsequent conception.”
Also, Dr. McKeeby and many other practitioners feel that asking a couple to wait for evaluation until after a third loss is insensitive. He says that in the past few years, the majority of patients coming to Shady Grove Fertility now for recurrent miscarriage are referred after their second loss.
Highest Tech Intervention
One situation that requires a higher-tech approach to answering the needs of women with recurrent pregnancy loss is in the case of what is called “balanced translocation,” a term referring to parents in which their chromosomes have missing or incorrectly located pieces. Men and women with such genetic occurrences almost never have any resulting conditions or symptoms that would clue them in on their chromosomal structure. Usually, they learn about it after having a blood karyotype — a picture of how one’s chromosomes are arranged – performed, and often following a miscarriage.
“In these cases, the risk of recurrence is somewhere between two and 10 percent, depending on random chance and on the gender of the parent who has the balanced translocation.” Dr. McKeeby explains that preimplantation genetic diagnosis, or PGD, can provide the answer that these patients need to have a healthy pregnancy and baby. PGD is basically a cellular biopsy and DNA analysis of an embryo created through in vitro fertilization, or IVF. In fact, the two main reasons for utilizing PGD is recurrent pregnancy loss and recurrent IVF failure.
“The most important thing in genetic testing is to try and do a karyotype on the pregnancy that is lost,” McKeeby says, “not only on the parents.”
Healthy Babies are the Norm
As disheartening as it is to experience even one miscarriage, and certainly more than that, the best news is that your chances are much greater at success in future pregnancies.
“If you find something that’s significant and you treat it,” explains McKeeby, “or you don’t find anything wrong, you have about a 70 to 75 percent chance of a successful pregnancy after that. Even if you’ve had four or five miscarriages, your odds with either a treated condition or no cause found are still around 68 percent for successful subsequent pregnancies.”
A lot of his job is reassuring patients — referred to as a “tender loving care” approach — that their chances for having a healthy baby are very good. Recurrent miscarriage patients in the Shady Grove Fertility practice receive the attention from staff and access to calming ultrasounds that they need to feel confident.
The Reality is Encouraging
Dr. McKeeby stresses that women who read about the details of miscarriage, its diagnosis and treatment, should avoid fretting that it may be their personal issue. While women in their 40’s do have higher chances of miscarriage, even they should not approach conception feeling initially worried. Younger women, in particular, have less statistical cause for concern. All women who are hoping to conceive should actively control the very important lifestyle factors — nutrition, folic acid intake, and maintaining optimal health — that can have a greater impact on their pregnancy chances.
“Patients should feel reassured overall that it’s far more likely they’ll have a successful pregnancy and healthy baby.”
