NEW YORK (Reuters Health) – Intravenous immunoglobulin (IVIG) is not helpful in the treatment of women with unexplained recurrent miscarriage and, for now, should not be used outside the research setting, conclude the authors of a report published online January 12 in the journal Fertility and Sterility.
Adaptation of the maternal immune system to accommodate the fetus is believed to be a prerequisite for a successful pregnancy, Dr. Baris Ata and colleagues from McGill University, Montreal, Quebec, Canada note in their report.
Immunologic disorders have been suggested to be related to recurrent miscarriage. However, with the exception off antiphospholipid syndrome, there is no clearly defined, or universally accepted, immunologic mechanism leading to miscarriage.
IVIG has been suggested to be beneficial in the treatment of recurrent miscarriage, although studies have yielded mixed results. One systematic review published in 2006 found no benefit of IVIG, while another, published that same year, found a significant increase in live birth rates in women with secondary but not primary recurrent miscarriage.
To reassess the potential benefits of IVIG in women with unexplained recurrent miscarriage, Dr. Ata and colleagues searched the published literature through mid-2010 for relevant randomized controlled trials. They found six trials (272 women with unexplained recurrent miscarriage) that met their inclusion criteria.
“The results suggest that IVIG does not increase the probability of live birth in women with unexplained recurrent miscarriage,” they report. The overall odds ratio for live birth was 0.92, “indicating a lack of a treatment effect with IVIG.”
Analyzing women with primary and secondary recurrent miscarriage separately did not alter this result, nor did analyzing the results by time of treatment (i.e., starting it before or after conception).
The results also do not support the “inadequate IVIG dosage theory,” the investigators say, as they failed to identify any trend suggesting IVIG could have been more effective in higher doses.
“Given the absence of a proven mechanism of action, and the lack of a diagnostic algorithm to identify patients who are likely to benefit from such treatment, IVIG administration for treatment of recurrent miscarriage is not justified outside the context of properly designed randomized controlled trials.”
They say three things need to happen before IVIG — “an intervention not without side effects” — can be offered to women with unexplained recurrent miscarriage. First, a specific pathologic process leading to recurrent miscarriage that is treatable with IVIG has to be identified; second, a reliable and reproducible diagnostic algorithm pinpointing who would benefit needs to be developed; and third, an optimal treatment schedule needs to determined.
Reference:
A systematic review of intravenous immunoglobulin for treatment of unexplained recurrent miscarriage
Fertility and Sterility, Published online January 12, 2011.
