There is no clear evidence suggesting that endometrial polypectomy is associated with a lower risk of future miscarriage in recurrent pregnancy loss (RPL) patients.

Introduction

Anatomical uterine abnormalities can be divided into congenital (CUA) and acquired uterine anomalies (AUA).

CUAs refer to Müllerian tract malformations which include septate, unicornuate, bicornuate and didelphic uteri. Their prevalence is higher in women with recurrent pregnancy loss (RPL) (13.3%) compared to the general population (5.5%).1 CUA are associated with increased risks of adverse outcomes during pregnancy. Women with a uterine septum or bicornuate uterus are at increased risk of first-trimester miscarriage, preterm birth and fetal malpresentation. Women with uterine didelphys have an increased risk of preterm labour and fetal malpresentation.2 Various hypotheses have been put forward to explain the pathophysiology. It has been suggested that the endometrium overlying a uterine septum is suboptimal for implantation, with an insufficient blood supply to support placentation and embryo growth. Other studies have suggested that there is also reduced uterine capacity and uncoordinated uterine contractions.2

AUAs include submucosal fibroids, endometrial polyps and intrauterine adhesions (IUA). Their prevalence is poorly researched amongst the RPL population, however, and can be as high as 12.9%.3 Risk factors for IUA include recurrent miscarriage and dilatation and curettage procedures, however the clinical relevance of IUA with regards to conception and miscarriage is unclear.4 Evidence for treatment is confined to a limited number of small observational studies and the rationales for treatment are similar to the hypotheses given for CUA.

Treatment

Traditionally, abdominal/laparoscopic metroplasty was performed in order to restore the shape of the uterus in women with bicornuate or didelphic uteri, however, due to significant adverse effects (prolonged hospital stay, intrauterine adhesion formation, uterine rupture during subsequent pregnancy) with no improvement in pregnancy outcome, this is no longer offered.7 The only congenital uterine anomaly with recognised treatment is uterine septum, through means of hysteroscopic resection. However, reproductive outcome data is scarce and conflicting.8,9,10

There is no clear evidence suggesting that endometrial polypectomy is associated with a lower risk of future miscarriage in recurrent pregnancy loss (RPL) patients. However, as polyps can be removed at the same time as hysteroscopic diagnosis with minimal additional risk, treatment is advised. There is no available trial data on the effect of submucosal fibroid resection or intrauterine adhesiolysis on the miscarriage rate specifically in RM patients, however, there is limited observational data suggesting a benefit with treatment.5,11

Bullet point guidance

Investigations and counselling

  • All women with RPL should have an assessment of the uterine cavity.
  • Women should be advised that both transabdominal and transvaginal ultrasonography will be performed to assess pelvic anatomy.
  • The preferred technique is three-dimensional ultrasonography.
  • Women with congenital uterine anomalies should be informed of the risks of adverse outcomes during pregnancy and that the only congenital anomaly where treatment is considered is in the case of uterine septum, ideally within an appropriate audit or research context.5
  • Women with acquired uterine anomalies should be informed that there is uncertainty about the impact of uterine fibroids, endometrial polyps and intrauterine adhesions upon reproductive outcomes. There is insufficient evidence to support routine surgical treatment of submucous fibroids, endometrial polyps and intrauterine adhesions in women with RPL.5
  • All women with congenital uterine anomalies or intrauterine adhesions who fall pregnant, whether or not they have been treated, should be managed using an appropriate preterm birth care pathway as outlined in the UK Preterm Birth Clinical Network Guidance.6

Treatment

  • Regarding congenital uterine anomalies:

o Surgical treatment of bicornuate or didelphic uteri is not recommended.5

o Hysteroscopic resection of a uterine septum should not be undertaken routinely but offered on an individualised basis by experienced specialists, based upon the clinical history and size of the uterine septum, and ideally within an appropriate audit or research context.12

  • Regarding acquired uterine anomalies:

o Surgical treatment may be considered for endometrial polyps, submucosal fibroids and intrauterine adhesions.5,13

o Surgical removal of intramural and subserosal fibroids is not recommended.5,13

References

  1. Chan YY, Jayaprakasan K, Zamora J, Thornton JG, Raine-Fenning N, Coomarasamy A. The prevalence of congenital uterine anomalies in unselected and high-risk populations: a systematic review. Human Reproduction Update. 2011;17(6):761-771.
  2. Chan YY, Jayaprakasan K, Tan A, Thornton JG, Coomarasamy A, Raine-Fenning NJ. Reproductive outcomes in women with congenital uterine anomalies: a systematic review. Ultrasound in Obstetrics and Gynecology. 2011 Oct;38(4):371-82.
  3. Jaslow CR, Kutteh WH. Effect of prior birth and miscarriage frequency on the prevalence of acquired and congenital uterine anomalies in women with recurrent miscarriage: a cross-sectional study. Fertility and Sterility. 2013 Jun;99(7):1916-22.e1.
  4. Hooker AB, Lemmers M, Thurkow AL, Heymans MW, Opmeer BC, Brölmann HA, Mol BW, Huirne JA. Systematic review and meta-analysis of intrauterine adhesions after miscarriage: prevalence, risk factors and long-term reproductive outcome. Human Reproduction Update. 2014 Mar-Apr;20(2):262-78. doi: 10.1093/humupd/dmt045. Epub 2013 Sep 29. PMID: 24082042.
  5. ESHRE Guideline Group on RPL, Bender Atik R, Christiansen OB, Elson J, Kolte AM, Lewis S, Middeldorp S, Nelen W, Peramo B, Quenby S, Vermeulen N, Goddijn M. ESHRE guideline: recurrent pregnancy loss. Human Reproduction Open. 2018 Apr 6;2018(2):hoy004. doi: 10.1093/hropen/hoy004. PMID: 31486805; PMCID: PMC6276652.
  6. UK Preterm Clinical Network. Reducing preterm birth. Guidelines for commissioners and providers. 2019 [www.tommys.org/our-organisation/our-research/premature-birth-research/reducing-preterm-birth-rates]. Accessed 12 October 2020.
  7. Maneschi F, Marana R, Muzii L, Mancuso S. Reproductive performance in women with bicornuate uterus. Acta Europaea Fertilitatis. 1993 May-Jun;24(3):117-20. PMID: 7985453.
  8. Venetis CA, Papadopoulos SP, Campo R, Gordts S, Tarlatzis BC, Grimbizis GF. Clinical implications of congenital uterine anomalies: a meta-analysis of comparative studies. Reproductive Biomedicine Online. 2014 Dec;29(6):665-83. doi: 10.1016/j.rbmo.2014.09.006. Epub 2014 Sep 21. PMID: 25444500.
  9. Rikken JFW, Verhorstert KWJ, Emanuel MH, Bongers MY, Spinder T, Kuchenbecker W, Jansen FW, van der Steeg JW, Janssen CAH, Kapiteijn K, Schols WA, Torrenga B, Torrance HL, Verhoeve HR, Huirne JAF, Hoek A, Nieboer TE, van Rooij IAJ, Clark TJ, Robinson L, Stephenson MD, Mol BWJ, van der Veen F, van Wely M, Goddijn M. Septum resection in women with a septate uterus: a cohort study. Human Reproduction. 2020 Jul 1;35(7):1578-1588. doi: 10.1093/humrep/dez284. PMID: 32353142; PMCID: PMC7368397.
  10. Rikken J, Kowalik C, Emanuel MH, Bongers M, Spinder T, Jansen FW, Mulders A, Padmehr R, Clark J, Van Vliet H, Stephenson M, Van Veen F, Mol BW, Van Wely M, Goddijn M. Septum resection versus expectant management in women with a septate uterus: a randomised controlled trial (NTR 1676). 36th Virtual Annual Meeting of the European Society of Human Reproduction and Embryology, Human Reproduction, Volume 35, Issue Supplement_1, July 2020, Pages i1–i522, https://doi.org/10.1093/humrep/35.Supplement_1.1
  11. Roy KK, Singla S, Baruah J, Sharma JB, Kumar S, Singh N. Reproductive outcome following hysteroscopic myomectomy in patients with infertility and recurrent abortions. Archives of Gynecology and Obstetrics 2010;282: 553-560.
  12. National Institute for Health and Care Excellence. Hysteroscopic Metroplasty of a Uterine Septum for Recurrent Miscarriage. NICE Interventional Procedures Guidance 510. London: NICE; 2015.
  13. Practice Committee of the American Society for Reproductive Medicine. Evaluation and treatment of recurrent pregnancy loss: a committee opinion. Fertility and Sterility. 2012 Nov;98(5):1103-11. doi: 10.1016/j.fertnstert.2012.06.048. Epub 2012 Jul 24. PMID: 22835448.