For women who have multiple miscarriages, the pain of repeated loss is often compounded by another reality. The causes behind miscarriage are complex and often difficult to identify, and even those conditions and associations proposed as causes are poorly understood.
But there is good news too. Women with recurrent miscarriages can benefit from comprehensive evaluation, treatment and support programs, such as the Recurrent Pregnancy Loss Program at Stanford. Even among those women whose miscarriages don’t have an identifiable cause, more than 80 percent of women who’ve had two or more miscarriages will ultimately have a successful pregnancy with supportive care.
Stanford Hospital & Clinics medical specialists shared this information at a recent community seminar, “Prevailing Over Recurrent Pregnancy Loss,” presented by Women’s Health at Stanford.
Although miscarriage is common – 30 percent of all women will experience at least one miscarriage in their lifetime, and 1-2 percent will have three or more – there have been relatively few well-conducted studies on its causes and treatments, said Ruth Lathi, MD, Director of the Recurrent Pregnancy Loss Program at Stanford Hospital & Clinics and assistant professor of obstetrics and gynecology. “We can do better than this. We need more research,” she said.
As many as 40 to 50 percent of miscarriages have no identifiable cause.
Some of miscarriage’s causes have been pinpointed. Endocrine problems, such as thyroid disease, are responsible for 15-20 percent of miscarriages; hypercoagulability, an increased tendency to develop blood clots, also causes 15-20 percent; maternal abnormalities in the uterus or cervix cause 10-15 percent; maternal genetic mutation causes 2-5 percent; and in 0.5-5 percent of cases, infection triggers a miscarriage. Older age and a history of previous miscarriages also increase the risk.
Some of these causes can be detected and treated. For women with thyroid dysfunction (hypothyroidism or hyperthyroidism), successful treatment reduces the risk of miscarriage and other adverse outcomes. For women with thyroid dysfunction (hypothyroidism or hyperthyroidism), successful treatment reduces the risk of miscarriage and other adverse outcomes. Recent studies have also shown that in selected women who have anti-thyroid antibodies (a condition affecting about 11 percent of reproductive-age women), treatment with the thyroid hormone levothyroxine can effectively decrease miscarriage rates.
Women who have hypercoagulability can be treated with therapies that interfere with blood clot formation, most commonly aspirin or heparin or both. Weight is another contributing factor, said Sun Kim, MD, assistant professor of medicine in the Division of Endocrinology. Research finds that being obese or underweight significantly increases pregnancy complications and the risk of miscarriage.
Given that one-third of Americans are obese, the impact of obesity on pregnancy outcomes is a growing public-health concern, Kim said. “Losing weight is hard, I don’t deny that,” she said. But she added that even moderate weight loss of 5-10 percent can significantly reduce the risk of miscarriage.
Considering the degree of grief and sadness that come with miscarriage, it’s not surprising that recurrent miscarriage is associated with higher rates of depression, said Katherine Williams, MD, clinical associate professor of psychiatry and behavioral sciences. While the incidence of major depression in general-population women is 5-10 percent, studies have found that in women who have had one miscarriage, the incidence rises to 10-20 percent, and to at least 30 percent in women who’ve had two or more miscarriages.
Many women worry that being depressed might cause a miscarriage, Williams said. While this question has not been adequately addressed by research, she emphasized that depression can be successfully treated through medication, psychotherapy or both. And, treating depression can help a woman take other steps to reduce her miscarriage risk, such as losing weight, taking medications as prescribed, and attending a support group.
Lathi knows that the quest for a successful pregnancy can become desperate. She cautioned that this urgency “can compel some women to try things that are outside of evidence-based medicine.”
Also, a pair of randomized controlled trials published in March and April found that the use of heparin and/or aspirin – commonly prescribed to women who have unexplained recurrent miscarriages – are no more effective in these cases than standard care.
Lathi instead emphasized the value of preconception evaluation and supportive care throughout the process. “We want to give women hope that even though there are a lot of unanswered questions, we have an evidence-based approach that we know helps a lot of women have a baby.”
Especially helpful, the specialists said, are multidisciplinary efforts like the Stanford Recurrent Pregnancy Loss Program, one of a handful of its kind in the U.S. The program offers comprehensive evaluation, treatment, follow-up and support from a team of physicians from several disciplines, including genetics, endocrinology, hematology, immunology, psychiatry and others. Those clinicians work together to share information, consult with patients, and meet to discuss complex cases.
“You don’t have to figure out what to do next or which doctor to see,” Lathi said. “We guide you through the process.”
Source: Stanford Hospital & Clinics