Comments on: Plan B: Literature Review (Part II) http://alesrarus.funkydung.com/archives/2452 A Rare Bird, A Strange Duck, One Funky Blog Sat, 19 Jul 2008 23:27:26 +0000 http://wordpress.org/?v=abc By: Mariana http://alesrarus.funkydung.com/archives/2452#comment-27265 Mariana Sun, 05 Nov 2006 01:35:01 +0000 http://alesrarus.funkydung.com/archives/2452#comment-27265 Based on that study, I would say Plan B does not affect the endometrial lining, but it does affect the length of the luteal phase due to progesterone insufficiency. 80% of those taking the pill before ovulation and before the LH surge failed to ovulate, those who took it after the LH surge or right after ovulation noticed no effect. Given the pregnancy "prevention" rate of Plan B is 89% (including people who had sex after ovulation), and this study showed a prevention of ovulation of 80%, I would NOT draw the conclusion that Plan B was primarily abortifacient. I would recommend any woman taking Plan B to monitor herself for ovulation and supplement with progesterone to prevent a short luteal phase. I would not recommend women taking Plan B on ovulation day or later, because it is either unnecessary, inneffective, or potentially abortifacient. To me, it seems that from the study that the primary mode of action of Plan B is to prevent ovulation, not to damage the endometrium (no evidence of this mode of action). It can shorten the luteal phase, but that seems to be due to a crash in hormones, and theoretically could be prevented through progesterone supplementation. Of course, the results of one small study are not conclusive in any way. Based on this document: <a href="http://www.nccbuscc.org/prolife/issues/abortion/ecfact.htm" rel="nofollow">http://www.nccbuscc.org/prolife/issues/abortion/ecfact.htm</a> It would be useful to know exactly when Plan B acts as an abortifacient and when it acts simply as a contraceptive. If the abortifacient action of Plan B is simply to shorten the luteal phase, the combination of a transvaginal ultrasound and progesterone supplements would be a good theoretical protocol to follow to avoid the misuse of the drug in cases of sexual assault. -Mariana
Given the pregnancy "prevention" rate of Plan B is 89% (including people who had sex after ovulation), and this study showed a prevention of ovulation of 80%, I would NOT draw the conclusion that Plan B was primarily abortifacient. I would recommend any woman taking Plan B to monitor herself for ovulation and supplement with progesterone to prevent a short luteal phase. I would not recommend women taking Plan B on ovulation day or later, because it is either unnecessary, inneffective, or potentially abortifacient.

To me, it seems that from the study that the primary mode of action of Plan B is to prevent ovulation, not to damage the endometrium (no evidence of this mode of action). It can shorten the luteal phase, but that seems to be due to a crash in hormones, and theoretically could be prevented through progesterone supplementation.

Of course, the results of one small study are not conclusive in any way.

Based on this document: http://www.nccbuscc.org/prolife/issues/abortion/ecfact.htm It would be useful to know exactly when Plan B acts as an abortifacient and when it acts simply as a contraceptive. If the abortifacient action of Plan B is simply to shorten the luteal phase, the combination of a transvaginal ultrasound and progesterone supplements would be a good theoretical protocol to follow to avoid the misuse of the drug in cases of sexual assault.

-Mariana]]> By: Lightwave http://alesrarus.funkydung.com/archives/2452#comment-26600 Lightwave Mon, 30 Oct 2006 14:47:07 +0000 http://alesrarus.funkydung.com/archives/2452#comment-26600 Maybe someone with a statistical background can help me out here. I know that any number of test subjects can be statistically significant depending on the desired confidence level one wants in the results. If we had statistics on the number of EC users, would we not be able to calculate the "confidence interval" for 45 test subjects? Thus we would know the confidence with which we can say these results apply to the general population. Would it not be fair to say that any confidence in these results (> 0%) is better than having no data and hence no confidence? i.e. the conclusions from data presented here is far more likely to be accurate than conclusions based on conjecture and assumptions on the effects of EC?
Would it not be fair to say that any confidence in these results (> 0%) is better than having no data and hence no confidence? i.e. the conclusions from data presented here is far more likely to be accurate than conclusions based on conjecture and assumptions on the effects of EC?]]> By: cjmr http://alesrarus.funkydung.com/archives/2452#comment-26146 cjmr Thu, 26 Oct 2006 23:58:20 +0000 http://alesrarus.funkydung.com/archives/2452#comment-26146 45 participants would be too small for a safety or efficacy study, but for a 'method of operation' study that is a reasonable number. By: Participatory Bible Study Blog » Blog Archive » Christian Carnival CXLV http://alesrarus.funkydung.com/archives/2452#comment-25999 Participatory Bible Study Blog » Blog Archive » Christian Carnival CXLV Wed, 25 Oct 2006 18:36:48 +0000 http://alesrarus.funkydung.com/archives/2452#comment-25999 [...] In the field of medicine and ethics, from Ales Rarus, we have Plan B: Literature Review (Part II). This is the second post in a series. Last time I looked at a couple literature reviews about the methods of action of Plan B emergency contraception (levonorgestrel, LNG). This time I’m presenting On the the mechanisms of action of short-term levonorgestrel administration in emergency contraception (Durand, et al., 2001). [...] By: Funky Dung http://alesrarus.funkydung.com/archives/2452#comment-25851 Funky Dung Tue, 24 Oct 2006 13:06:56 +0000 http://alesrarus.funkydung.com/archives/2452#comment-25851 I haven't read anything more current than 2001 about fallopian tube dysfunction. The Croxatto, et al., paper I presented in Part I had this to say: <blockquote>Alterations in embryo transport through the fallopian tube or uterus following EC, are also difficult to explore. Delayed transport or retention in the tube cannot be excluded a priori, although no increased incidence of tubal pregnancy has hitherto been reported with the current methods. Accelerated transport through the tube appears unlikely since neither estradiol nor progesterone given in high doses right after ovulation have this effect in women [102].</blockquote>
Alterations in embryo transport through the fallopian tube or uterus following EC, are also difficult to explore. Delayed transport or retention in the tube cannot be excluded a priori, although no increased incidence of tubal pregnancy has hitherto been reported with the current methods. Accelerated transport through the tube appears unlikely since neither estradiol nor progesterone given in high doses right after ovulation have this effect in women [102].
]]> By: Jerry http://alesrarus.funkydung.com/archives/2452#comment-25753 Jerry Tue, 24 Oct 2006 02:14:44 +0000 http://alesrarus.funkydung.com/archives/2452#comment-25753 Fallopian tube dysfunction is another postfertilization effect that has been mentioned. Have you seen anything on that? (And did that recent JAMA review I sent you prove at all useful?) Stuff: for a fairly involved human study, 45 isn't necessarily too bad...
Stuff: for a fairly involved human study, 45 isn't necessarily too bad…]]> By: Stuff http://alesrarus.funkydung.com/archives/2452#comment-25713 Stuff Mon, 23 Oct 2006 21:44:27 +0000 http://alesrarus.funkydung.com/archives/2452#comment-25713 Does anyone know whether 45 participants is statistically appropriate to draw generalizations from their findings? I know there's all kinds of ethical and logistical problems with obtaining more, but I seem to remember from way, way back in pharmacy school tests you could perform to give more credibility to your study by showing the group sizes were appropriate. 45 just seems kind of small to me. Otherwise the study seems well-done. By: luminousmiseries http://alesrarus.funkydung.com/archives/2452#comment-38618 luminousmiseries Tue, 30 Nov 1999 00:00:00 +0000 http://alesrarus.funkydung.com/archives/2452#comment-38618 <!--%kramer-pre%--> brings us "Some thoughts on Suffering." Recently Ales Rarus looked at a couple literature reviews about the methods of action of Plan B emergency contraception (levonorgestrel, LNG). This time it's Plan B: Literature Review (Part II): On the the mechanisms of action of short-term levonorgestrel administration in emergency contraception (Durand, et al., 2001) If the blog name The Kitchenmadonna doesn't make you want to click on through then maybe the post title <!--%kramer-post%--> brings us "Some thoughts on Suffering." Recently Ales Rarus looked at a couple literature reviews about the methods of action of Plan B emergency contraception (levonorgestrel, LNG). This time it's Plan B: Literature Review (Part II): On the the mechanisms of action of short-term levonorgestrel administration in emergency contraception (Durand, et al., 2001) If the blog name The Kitchenmadonna doesn't make you want to click on through then maybe the post title ]]>