Companion Drug to RU-486 Could Be Dangerous If Not Taken Properly

Misoprostol, a companion drug to RU-486 that is used during medication abortions, is safe when taken orally but could reduce the body’s immune response when used vaginally, according to a study released Monday by researchers at the University of Michigan.

Vaginal use of the drug may be responsible for the deaths by rare infection of eight women since 2000, the study’s authors said.

Misoprostol is approved by the U.S. Food and Drug Administration to be taken orally along with RU-486 to end an early-term pregnancy. RU-486 stops the pregnancy, while misoprostol allows the uterus to contract and the cervix to dilate so that a woman will expel the embryo. More than a half-million women in the United States have used the two drugs safely since the FDA approved the method in 2000.

But many women have used the drug vaginally, a delivery method the FDA has not evaluated.

Misoprostol is a synthetic version of a natural prostaglandin called E2. Prostaglandins are compounds that regulate the body’s immune response, and E2 can be a potent suppressor of that response, said Dr. David Aronoff, an infectious disease specialist who led the study.

His immunology lab began its study after the U.S. Centers for Disease Control reported in 2005 on four of the deaths, all of healthy women who died after medication abortions. Another had died as well.

"What struck me in those five cases is the women had previously been healthy, then died after taking fairly high doses of synthetic prostaglandin E2, which is misoprostol," Aranoff said.

"Vaginal application seems to be more effective, and women tolerate it better. It became quite popular," he added. "But in Europe they don’t use misoprostol vaginally, and no deaths had been reported there. We wondered if maybe high concentrations of this stable prostaglandin in the vaginal tract might lower a women’s ability to fight bacterial infections."

In animal and cell culture studies, the researchers found that when used vaginally, misoprostol can allow Clostridium sordellii, a normally non-threatening bacterium, to flourish and cause deadly infection. When absorbed through the stomach, however, the drug did not compromise immune defenses or cause illness.

Women rarely harbor the infection vaginally in the first place, Aranoff said, indicating an additional risk factor must exist in order for the infection to occur.

"It needs to be emphasized that the termination of pregnancy with these is drugs very safe," he said. "What our research does is maybe make a safe procedure even safer. These infections are very rare."

When taken orally, misoprostol gets absorbed into the bloodstream and distributed throughout the body. Vaginal use forces the drug to be absorbed initially in the soft tissue, leading to high concentration in one area before the subsequent absorption into the bloodstream.

Misoprostol is occasionally used as an immunosuppressant for organ transplant patients and most commonly as prevention against stomach ulcers by those taking high doses of aspirinlike compounds.

"Those patients show no immunosuppressant problems," Aranoff said. "That further substantiates how safe this drug is when taken by mouth."

In 2006 Planned Parenthood, the nation’s largest provider of abortions, stopped offering misoprostol vaginally as a precaution. The study supports that decision, Aranoff said.

It appears online ahead of print in the Journal of Immunology.

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  • invalid-0

    im 22 i ve heard my first born when i was only 18.
    Im now pregnant and am confussed,worried about this working now, i ve got my own house ,my partner wants this and he s very supportive about it,but i still feel there some of the things that could ve been sorted out before this.Im also worried im going to dissappoint my family and friends who are looking up to me.I am thinking about terminating but i dont feel right about it. I would hate to loose my partner because of this and according to my religion its also wrong. And keeping it im scared of responsibilities,im worried im gonna be judged and i dont wanna dessapoint people around me.Their happiness come first is important.
    Pls share with me few advises. Im desperate.

  • invalid-0

    While the more research into this field the better, it is important to remember that careful review of all available evidence shows that fatal infections of Clostridium sordellii following mifepristone abortion are highly unlikely to be a drug related effect. RHTP attended the 2006 scientific workshop hosted by the FDA, CDC and NIH that reviewed data on these infections and the CDC confirmed that there have also been similar deaths among women following live birth and spontaneous miscarriage. Internationally, vaginal use of misprostol has been standard in the United Kingdom, Sweden and South Africa with no cases of C. sordellii shock being reported. In other words, it became clear that the infections were more likely linked to the end of pregnancy, rather than to medical abortion, or abortion in general.

    You can find more information specifically about C. sordellii infection here and more information about mifepristone abortion here.

  • invalid-0

    Sweetie, that’s not something anyone can decide for you. You have to look into your heart and figure out whether or not you want or are able to have another kid. I’ve been there and know it’s tough what you’re going through and I wish you the best in a difficult situation.

  • invalid-0

    Nearly 1 million women in the United States have used misoprostol in combination with mifepristone for first trimester pregnancy termination. Countless more women have used misoprostol alone for second trimester termination and labor induction. Yet this one study – conducted in rats – is being used widely by advocates and media to criticize vaginal use of misoprostol. For the many reasons detailed below, we believe the author’s conclusions are unjustified, and we counsel for greater caution in connecting this rat study with public health issues in human populations.

    1. Misoprostol was not administered vaginally but via intra-uterine injection. The effect of a drug administered via intra-uterine injection has not been proven to be similar to vaginal administration.

    2. The bacteria were introduced directly into the uterus – a model that does not mimic the presumed nature of pelvic infection with C. sordellii among women.

    3. The dose of misoprotol given to rats was nearly 20 times the standard dose used for pregnancy termination.

    4. Immune suppression in humans given misoprostol orally appears to last only 8 to 10 hours. [1] Yet, in the reports of C. sordellii pelvic infections, women presented with symptoms 3 to 5 days following misoprostol exposure.

    5. Caution is warranted when applying results from non-human research to humans. [2]

    6. The rats were not pregnant, an immune state markedly different from pregnancy.

    7. There is no evidence that vaginal misoprostol use is uniquely responsible for these infections. A case was recently reported following non-vaginal misoprostol administration.[3] The estimated relative risk among women taking misoprostol vaginally and non-vaginally in the United States is nearly identical. In United Kingdom, Sweden and South Africa, where vaginal misoprostol use is the standard of care for medical abortion, hundreds of thousands of women have used misoprostol vaginally without a single reported infection.

    The potential impact of misconstruction and misuse of these data highlights the important responsibility of scientists to fairly interpret and not sensationalize research results and the responsibility of advocates and media have in report research results carefully and accurately.


    [1] Waiser, J.T. Bohler, J. Stoll, B. Schumann, K. Budde, H-H. Neumayer. 2003. The immunosuppressive potential of misoprostol – efficacy and variability. Clin. Immunol.
    109: 288-94.

    [2] Mestas J. Hughes C.C.W. 2004. Of mice and not men: Difference between mounse and human immunology. J. Immunol. 172: 2731-8.

    [3] Cohen A.L., J. Bhatnagar, S. Reagan, S.B. Zane, M.A. D’Angeli, M. Fischer, G. Killgore, T.S. Kwan-Gett, D.B. Blossom, W.J. Shieh, J. Guarner, J. Jernigan, J.S. Duchin, S.R. Zaki, L.C. McDonald. 2007. Toxic shock associated with Clostridium sordellii and Clostridium perfringens after medical and spontaneous abortion. Obstet. Gynecol. 110:1027-33.

  • invalid-0

    My fellow mom, I can’t tell you what to do. I hear you say that your partner is very supportive but no matter how supportive he is, it is you that will be responsible for how your child or any other children you have, turn out. Us moms are the ones who are blamed when our children have poor judgment and make mistakes. I think that is something for you to keep in mind when making your decision. Also, nothing against single moms and women who are unmarried, but if your partner was really committed to you, he would prove it by becoming your husband. The big deal about that is you two would legally be immediate family and it would prove just how committed he is to you. That is because it is much easier to “break up” with someone than to “divorce” someone. Something else to consider, I do know from research that the child you had at 18 is at risk for many problems because you had him/her as a teenager, including not finishing high school, drug and alcohol abuse, and involvement in both the juvenile and adult criminal justice systems. That’s not my opinion, that is years and years worth of research. And that is because there is still so much growing up to do between the teenage years and through our mid-twenties (for example, the human brain does not stop developing until we are about 25 years old! Wow!) The point being that you need to give even more as a mom than someone who had their baby at age 25 or later. Something else to consider is that right now, your pregnancy is only the potential to be a person, while the child you already have is already a person. You need to consider your child’s needs first. Will having another baby put your child at a disadvantage? Can you afford quality childcare and education now? How will that change if you have to divide those funds by two? What about your own ability to be a parent? Are you a calm and patient person? Are you truly unselfish and put your child first? Or maybe you do that but secretely resent your child for that? Or maybe you love what your child loves wholeheartedly? Or are you emotionally unstable (easily angered, quick temper, use drugs or alcohol to cope, have frequent mood swings, blow things out of proportion too often, etc), or impulsive and prone to making poor judgments as it is? These are things you need to consider while doing some soul searching for your decision. One thing I can tell you for sure is that you must put the child you already have first. And you need to be honest with yourself and do a lot of soul searching. Are you a good mom now? Honestly. Do you really have it in you to do it again? Is your partner REALLY a good dad? How is he with your child? Also, you MUST look at your own life satisfaction. What about your own life goals? Your own education or career? That is important because if you are happy with YOUR OWN life, then that will positively influence your child’s life. If you are not happy with your life, then it will negatively influence your child’s life. That’s just the way that is. I hope this gave you a starting point in the many things you need to consider as you decide what is best for you, your child, and your family. God will love you no matter what you decide. Just please use good judgment.