Update Dec '10: Clinical trials and patents relevant to Asherman's syndrome

Clinical trials:

There are a number of trials involving the use of misoprostol for miscarriage management (note: I am not including studies on misoprostol use for pregnancy terminations because this choice is already routinely available to women who abort. It is not routinely- let alone occasionally-available to those who miscarry). As a blog which promotes prevention, these are naturally included. Below is more information and links to the studies.

Optimal Treatment of Miscarriage OR
Which is the Optimal Treatment for Miscarriage With a Gestational ac in the Uterus and Which Factors Can Predict if the Treatment Will be Successful?Region Skane, Kvinnokliniken, University Hopsital MAS Malmo Sweden.
Study type: Open labelled randomized trial (parallel assignment).
Aim: To compare the number of women with a complete miscarriage after 10 days between expectant management versus treatment with 800 micrograms of misoprostol intravaginally in women with an an incomplete miscarriage before 14 weeks and a gestational sac retained in the uterus.
link: http://clinicaltrials.gov/ct2/show/NCT01033903?term=miscarriage&rank=5

A Randomized Trial of Two Regimens of Misoprostol for Second Trimester Termination for Intrauterine Fetal DeathAmerican University of Beirut Medical Center
Study type: Open labelled, randomized controlled crossover trial.
Aim: To compare the safety, efficacy and patient satisfaction of vaginal versus sublingual administration of misoprostol (400 mcg every 4 hours until delivery. Time frame=24 hours)
link: http://clinicaltrials.gov/ct2/show/NCT00141895?term=misoprostol&rank=7

Sublingual Misoprostol Versus Standard Surgical Care for the Treatment of Incomplete AbortionGynuity Health Projects, Egypt, Mauritania, Niger.
Study type: Open labeled randomized controlled trial.
Aim: To compare the safety and efficacy of 400 mcg sublingual misoprostol to standard surgical curretage (D&C or MVA) for incomplete abortion (ie. retained products of conception). Presumably either spontaneous or induced.
link: http://clinicaltrials.gov/ct2/show/NCT00466999?term=misoprostol&rank=50

Non Surgical Management for Uterine Residua After Pregnancy Termination, Abortion or DeliveryHaEmek Medical Center, Israel
Study type: open labelled randomized trial (parallel assignment)
Aim:To compare the outcome of misoprostol treatment (intravaginal, 800 mcg) and expectant management in the case of intrauterine residua after completion of pregnancy.
link: http://clinicaltrials.gov/ct2/show/NCT01134926?term=misoprostol&rank=56

Misoprostol for Treatment of Fetal Death at 14-28 Weeks of PregnancyGynuity, California, Illinois, Boston, New York.
Study type: Double blinded randomized trial, parallel assignment.
Aim: To establish the safety and effectiveness of two different doses of the prostaglandin E1 analogue misoprostol administered buccally as a treatment for fetal death at 14 - 28 weeks, inclusive, of pregnancy.
link: http://clinicaltrials.gov/ct2/show/NCT00671060?term=misoprostol&rank=24

Effect of Colony Stimulating Factor on Poor Endometrial Development During IVF
Official Title: G-CSF and Endometrial Growth, Embryo Implantation and Pregnancy Following FET or Donor ET
The Center for Human Reproduction (CHR) is conducting a double-blind, randomized cross over trial to investigate the effect of G-CSF on endometrial thickness in women who have failed reaching minimal endometrial thickness by standard treatments. Outcome measures will include endometrial thickness (must be >7mm for transfer), implantation and pregnancy rates compared to control patients. The study will be conducted in women undergoing transfer of previously cryopreserved embryos or transfer of embryos from donor eggs. 

There are published studies on the use of Vitamin E (tocopherol), Pentoxyfilline, and Sildenafil in women with a thin endometrium (some of whom have a history of Asherman’s syndrome (1-4)). To my knowledge this is the first trial using G-CSF for this purpose.
For more information see:
http://clinicaltrials.gov/ct2/show/NCT01202643?term=asherman+syndrome&rank=1

Safety of Leaving Cook Balloon Uterine Stent in Uterus for One Month
The Department of Obstetrics and Gynecology, Shin-Kong Wu-Ho-Su Memorial Hospital in Taiwan is conducting an open label randomized controlled trial to investigate the feasibility of leaving an intrauterine Cook balloon in the uterus for 1 month. The experimental arm of the study will be fitted with a uterine Cook stent while the control will not. Both groups will have swabs taken for culture just before hysteroscopic adhesiolysis and 30 days later, during second look hysteroscopy to evaluate the outcome of surgery.

The practice of leaving a Cook Balloon stent in the uterus for this length of time is used by some Asherman’s syndrome specialists in cases of severe and recurrent intrauterine adhesions (personal communication). In the above study there is no mention of antibiotic use, however the specialists that use the Cook balloon or Foley catheter prescribe antibiotic prophylaxy during the entire therapy to prevent the potential infection. The results of the study will also reveal the effectiveness of the Cook balloon in preventing adhesion recurrence compared to no stent. Previously there was a study comparing the IUD (3 cycles) to the Foley catheter (10 days), however the method of ‘adhesiolysis’ was blind D&C, not dissection of adhesions under direct hysteroscopic view (5). As blind D&C is the most common cause of intrauterine adhesions, it is difficult to know if the previous findings are due to the barrier method used or to fortuitous variations in the success of ‘surgery’ which is carried out blindly.

For more information see: http://clinicaltrials.gov/ct2/show/NCT01167296?term=uterine+adhesions&rank=2


SIGnificance of Routine Hysteroscopy Prior to a First 'in Vitro Fertilization'(IVF) Treatment Cycle (inSIGHT)
A multicenter single-blinded (caregiver) randomized intervention trial is being undertaken in the Netherlands to assess the cost effectiveness of screening women for intauterine abnormalities using hysteroscopy and SIS (saline infusion sonography) prior to fertility treatment (IVF/ICSI). If abnormalities are found (defined as the existence of a septum, endometrial polyp, submucous myoma, adhesions or endometritis) these will be treated on the spot, using scissors, Versapoint, grasping forceps, polypsnare or antibiotics. The primary outcome measure is cumulative ongoing pregnancy rate and live birth after randomization within 18 months of IVF/ICSI. Secondary outcome measures include cumulative implantation rates, miscarriage rates, and comparative cost calculations.

Studies have shown that minor intrauterine abnormalities can be found in 11-40% of infertile women with a normal tranvaginal sonography. Detection and treatment of these abnormalities by office hysteroscopy have led to a 9-13% increase in pregnancy rate. Therefore, it is increasingly advised to screen all infertile women on intracavitary pathology prior to the start of IVF/ICSI.

Note that women with recurrent miscarriage are excluded from the study, when it is known that women with uterine abnormalities (congenital or acquired) are at a risk of repeated pregnancy loss. This exclusion is perhaps added in order to eliminate women who have other causes of infertility that are not due to anatomical anomalies and which cannot be diagnosed and corrected via hysteroscopy. However, this possible bias could have been avoided by excluding women who tested positive for other conditions known to cause recurrent miscarriage. I also wonder how effective outcomes will be in the experimental arm if IVF/ICSI is commenced immediately after treatment, without assessing the state of the cavity (IUA often recur, and IUA are a common consequence of septum correction and myomectomy). Furthermore, would it not be possible to answer this clinical question by reviewing the prevalence of uterine abnormalities in infertile and subfertile women, the cumulative implantation, pregnancy and live birth rates following treatment of these conditions, and analyzing the costs versus benefits ratio? For example, if past studies have shown that more than 10% of infertile women have an intrauterine pathology, and 40% of these women have a live birth after treatment, is it not justified to perform a diagnostic hysteroscopy prior to IVF/ICSI?

For more information: http://clinicaltrials.gov/ct2/show/NCT01242852?term=uterine+adhesions&rank=8

Note: There appears to be an error in the table describing the intervention and control arms of the study.

Patents

Patent Applications:
WO 2010/05/054068 A2 Cyclic adenosine monophosphates (cAMPs) for reducing the formation of adhesions. This world patent application claims the use of various derivatives of cAMPs for the reduction of adhesion formation for reducing inflammation or tissue damage after abdominal or pelvic surgery.
Jackson, EK. Cyclic adenosine monophosphates for reducing the formation of adhesions. 14 May 2010.
More info http://www.ibridgenetwork.org/university-of-pittsburgh/cyclic-adenosine-monophosphates-for-reducing-the-formation-of

In contrast to adhesion barriers, the invention would not involve placing a foreign body in the surgical cavity. Present adhesion barriers can cause immunological reactions. Also, the cyclic adenosine monophosphates are naturally-occuring substances and therefore should be quite safe. The cyclic adenosine monophosphates can be quickly and easily administered with a syringe. It can be used in minimally-invasive surgery, the future of surgery, and should be effective even if blood is in the surgical field. It is likely that the invention will be more efficacious than existing adhesion barriers.

Theoretically it could also be useful for intrauterine adhesions as many of the gel barriers used for pelvic surgery are also being used/trialled post adhesiolysis in Asherman’s syndrome treatment.So far there are only limited data on the efficacy of gel barriers in the treatment of Asherman’s syndrome (6-8). One of the difficulties of using gels is that they do not stay in a fixed position which is essential for them to be effective.

Granted Patents:
2005/0084,508 A61K Topical anesthesia formulation for bodily cavities
Innovators: Vancaillie, Thierry G; Hewitt, Alan Ernest
A topical anesthetic used for in-office hysteroscopy has recently been patented. The pH is adjusted to that of the body’s to optimize the effectiveness of the anesthetic.One of the inventors is an Asherman’s syndrome specialist. He has also developed a device for administering the anesthetic.
More info: http://www.patentbuddy.com/patentdetails/2402425


References
1. Acharya S, Yasmin E, & Balen AH. The use of a combination of pentoxifylline and tocopherol in women with a thin endometrium undergoing assisted conception therapies – a report of 20 cases Human Fertility, December 2009; 12(4): 198–203.
2. Batailles N, Oliviennes F, Lefaix JL, Chaouat G, Frydman R, Delanian S. Combined treatment by pentoxifylline and tocopherol for recipient women with a thin endometrium enrolled in an oocyte donation programme. Hum Rep 2002;17(5):1249-53.
3. Sher G, Fisch D. Effect of vaginal sildenafil on the outcome of in vitro fertilization (IVF) after multiple IVF failures attributed to poor endometrial development. Fertil Steril. 2002 Nov;78(5):1073-6.
4. Zinger M, Liu Thomas JH, MA. Successful Use of Vaginal Sildenafil Citrate in Two Infertility Patients with Asherman’s Syndrome. JOURNAL OF WOMEN’S HEALTH 2006;15(4):,442-4.
5. Orhue AA, Aziken ME, Igbefoh JO. A comparison of two adjunctive treatments for intrauterine adhesions following lysis. Int J Gynaecol Obstet; 2003;82:49-56.
6. Abbott J, Thomson A, Vancaillie T. SprayGel following surgery for Asherman’s syndrome may improve pregnancy outcome. J Obstet Gynaecol 2004;24:710-1.
7. Acunzo G, Guida M, Pellicano M, Tommaselli GA, Di Spiezio Sardo A, Bifulco G, et al. Effectiveness of auto-cross-linked hyaluronic acid gel in the prevention of intrauterine adhesions after hysteroscopic adhesiolysis: a prospective, randomized, controlled study. Hum Reprod2003;18:1918-21.
8. Metwally M, Watson A, Lilford R, Vandekerckhove P. Fluid and pharmacological agents for adhesion prevention after gynaecological surgery. Cochrane Database Syst Rev2006;(2): CD001298. doi: 10.1002/14651858.CD001298.pub3.

Relevant links:
Understanding Clinical Trials

How AS causes infertility or miscarriages

Asherman’s syndrome (AS) can lead infertility in a number of ways. No two cases are identical and it can manifest as infertility according to how and which parts of the reproductive anatomy is affected. AS is characterized by intrauterine adhesions (IUA) and/or fibrosis (non-functional scar tissue).

Infertility may be caused by adhesions occluding the tubal ostia, uterine cavity, or the cervix, thereby interfering with the migration of sperm or implantation of the embryo (1). The presence of defective endometrium in the fundus and ostia which are partially obliterated by the adhesions may also predispose women to tubal and cervical pregnancies (2,3). Partial obstruction of tubes can lead to pregnancy complications such as ectopic pregnancy because the fertilized egg may be physically impeded from migrating to the uterus for implantation. If ostial obstruction is so extensive that it cannot be corrected through hysteroscopic adhesiolysis, in vitro fertilization is the only possibility for a biological offspring (providing that the rest of the uterus is functional and adhesion free). Cervical pregnancy (another form of ectopic pregnancy) may occur if the embryo implants in the cervix. Adhesions involving the cervix may result in the cervix being closed (outlet obstruction). This obviously prevents the sperm from encountering the egg. It has also been noted that in women with outlet obstruction due to adhesions blocking the lower uterus or cervix, endometrial measures are thinner than in women where adhesions are limited to the upper uterus (4). It is thought that the underlying cause of this is a feedback loop to prevent haematometra from occurring. Haematometra is the formation of a large clot of blood from trapped menstrual debris and it very rarely occurs in the former subgroup of women.

Another possible way Asherman’s syndrome can result in infertility is by causing endometriosis. Some authors have noted that women with extensive adhesions either in the uterus or cervix, blocking menstrual flow, later develop endometriosis (5). This was discovered because laparoscopic (keyhole) surgery is sometimes carried out at the same time as hysteroscopy when performing adhesiolysis of IUA. Laparoscopy helps to prevent uterine perforation in severe cases where it may be difficult to judge the limits of the uterine cavity. Endometriosis is the growth of endometrial lining outside of the uterus. It can occur anywhere in the body, though most commonly occurs in the abdomen. Although the cause(s) of endometriosis remain unknown, one of the theories put forth by John A. Sampson is known as the theory of retrograde menstruation. It speculates that a back flow of blood and debris through the fallopian tubes and into the abdomen enables its implantation to the peritoneal surface (the lining of the abdominal cavity) where it can proceed to invade the tissue as endometriosis. (As an aside to those who practice yoga, this is why inverted positions such as headstands are avoided during menstruation). Endometriosis itself can lead to infertility by causing pelvic adhesions (Note: not to be confused with intrauterine adhesions which occur INSIDE the uterus). Pelvic adhesions (or extrauterine adhesions) can twist and distort the fallopian tubes and prevent fertilization or implantation.

Many women who have had Asherman’s syndrome develop a thin endometrium even after surgical correction and hormonal therapy to stimulate endometrial regeneration. An optimal thickness of the endometrium (>8mm) is considered to be one of the prerequisites for successful implantation of the embryo. Thin endometrium can be caused by either too much of the endometrium having been removed during D&C (or other uterine surgery) or cervical obstruction (as described above). A thin endometrium may be unresponsive to hormones (6) and may lead to infertility in the form of implantation failure or early miscarriages known as ‘chemical pregnancies’ due to a lack of blood supply and poor placental perfusion. Thin endometrium can also occur in women who have had D&Cs, even if they did not develop Asherman’s syndrome. In fact, a recent study found that the endometrium of women is thinner for about 6 months after a D&C (7). A recent study suggests that treatment with tocopherol (ie. vitamin E) and pentoxifylline may help to thicken the endometrium (8), improving implantation. Of course IUA must be removed before pregnancy can be attempted.

The exact mechanisms by which IUA predispose to miscarriages are unknown, however, it is suspected that constrictions of the uterine cavity by adhesions, lack of adequate functional endometrium to support implantation and defective vascularisation of the residual endometrial tissue due to fibrosis may account for repeated pregnancy loss (9). If an embryo implants in an adhesion or a fibrotic region, it will not grow successfully because it will not have an adequate blood supply, essential for providing the growing embryo with oxygen and nutrients. This can lead to miscarriage. Interestingly, this is analogous to the situation where women with Mullerian malformations such as septate uterus often undergo miscarriage when the embryo implants in the septum (10). If IUAs obstruct the openings of one or both of the fallopian tubes (known as ostia) this prevents the sperm from fertilizing the egg (which normally happens in the fallopian tubes after ovulation).

There is another potential cause of second trimester miscarriage which has been often reported in women with a past history of Asherman’s syndrome: cervical incompetence, also known and cervical insufficiency, however, I will write about this under a future blog topic, post-Asherman’s syndrome obstetric complications, since these miscarriages are not due to adhesions or fibrosis per se but to previous dilations of the cervix during surgeries.


As a consequence of the above, many women who have untreated Asherman’s syndrome are either unable to conceive, or suffer from repeated miscarriages. However, depending on the location, extent and severity of IUA/fibrosis, patients may conceive and carry a pregnancy without treatment. This is not recommended and is usually a chance finding on ultrasound when an adhesion or synechia is detected. There have been isolated case reports of successful and uncomplicated pregnancies in the presence of IUA (11). In the best case scenario, the adhesions are minimal and thin, stretching with the pregnancy such that it does not impinge on the growth of the fetus or uterus. However, women are strongly advised to use contraception to avoid pregnancy until surgical correction of adhesions to avoid pregnancy complications. In women who conceive without removal of adhesions, the reproductive outcome is usually poor: in one well known study, it was reported that of the 46% of patients with untreated IUA who conceived, 40% of the pregnancies ended in spontaneous miscarriage, 12% of which were ectopic. Of the viable pregnancies, 23% delivered prematurely and 13% had placenta accreta with only 53% delivering viable infants (12). Obviously, the more severe the classification of AS, the more likely complications are to occur if a pregnancy occurs. On the other hand, pregnancy itself is probably less likely to occur in more severe cases. Note that these complications may also occur in women after treatment of Asherman’s syndrome, however not as frequently. This will be covered in a future blog.

The moral of the story is: get treated by a trusted Asherman’s specialist if you have Asherman’s syndrome and make sure the uterine cavity is clear (via a follow up hysteroscopy or HSG) and that adhesions have not recurred before trying to conceive. Even better, avoid getting Asherman’s syndrome by using alternatives to D&C.


References


1.Yu, D, Wong, YM, Cheong, Y, Xia, E, and Li, TC. Asherman syndrome--one century later. Fertil Steril 2008;89(4):759-79.

2. Dicker, D, Feldberg, D, Samuel, N, and Goldman, JA. Etiology of cervical pregnancy. Association with abortion, pelvic pathology, IUDs and Asherman's syndrome. J Reprod Med 1985;30(1):25-7.

3. Forssman, L. Posttraumatic intrauterine synechiae and pregnancy. Obstet Gynecol 1965;26(5):710-3.

4. Lo ST, Ramsay P, Pierson R, Manconi F, Munro MG, Fraser IS. Endometrial thickness measured by ultrasound scan in women with uterine outlet obstruction due to intrauterine or upper cervical adhesions.Hum Reprod. 2008 ;23(2):306-9. Link

5. Palter. SF, High Rates of Endometriosis in Patients With Intrauterine Synechiae (Asherman's Syndrome). Fertility and Sterility 2005; 86 (null):S471-S471. Link

6. Shufaro, Y, Simon, A, Laufer, N, and Fatum, M. Thin unresponsive endometrium--a possible complication of surgical curettage compromising ART outcome. J Assist Reprod Genet 2008;25(8):421-5.

7. Moon KS, Richter KS, Levy MJ, Widra EA. Does dilation and curettage versus expectant management for spontaneous abortion in patients undergoing in vitro fertilization affect subsequent endometrial development? Fertil Steril. 2009;92(5):1776-9. PMID 19560759

8. Acharya S, Yasmin E, Balen AH. The use of a combination of pentoxifylline and tocopherol in women with a thin endometrium undergoing assisted conception therapies--a report of 20 cases. Hum Fertil (Camb). 2009;12(4):198-203. Link

9. Polishuk, WZ and Sadovsky, E. A syndrome of recurrent intrauterine adhesions. Am J Obstet Gynecol 1975;123(2):151-8.

10. Golan, A, Schneider, D, Avrech, O, Raziel, A, Bukovsky, I, and Caspi, E.
Hysteroscopic findings after missed abortion. Fertil Steril 1992;58(3):508-10.

11. Klatsky PC, Tran ND, Strachowski L. A pregnancy complicated by endometrial scarring. Fertil Steril. 2009;91(6):2707-8.

12. Schenker, JG and Margalioth, EJ. Intrauterine adhesions: an updated appraisal. Fertil Steril 1982;37(5):593-610.