Figure.3
Hysteroscopy and diagnostic laparoscopy with dye test done in 2021. Cervix was noted to be pin-hole and very difficult to dilate, foreign body was seen and removed from the endometrial cavity, the endometrial cavity otherwise looks normal. Laparoscopy revealed left sided physiological adhesion of bowel to the pelvic side wall, left tube looks inflamed but both tubes are positive for dye test and both ovaries look normal. Histology of the foreign body showed fragments of dead bone.
Discussion
This case highlights the difficulty in diagnosing the cause of her secondary infertility and abdominal discomfort because the first ultrasound scan as well as the MRI scan did not show any foreign body inside the endometrium. Potential differential diagnosis may include osseous metaplasia driven by chronic inflammation causing destrophic calcification (3) and endometrial ossification driven by chronic inflammation as well as tissue destruction in mature endometrial stroma. (4) The fact that the segment retrieved from hysteroscopy looks like a fetal long bone and the histology showed dead bone fragment and no active tissue goes against these two differential diagnosis.
Fetal bone fragment residing in the endometrium can act as a foreign body causing chronic inflammation to the endometrial environment, inhibiting implantation of the embryos and therefore cause secondary infertility. The effect is similar to having an IUCD in situ. It is also suggested that the fetal bone may have a direct toxic effect to the developing embryo therefore causing infertility. (4)
Currently, hysteroscopy is used in most of the case reports as the treatment of choice to retrieve foreign body to either treat the infertility (1-4) or menstrual complaints, including chronic pelvic pain. (5) However, there is lack of guidance nationally as to the gold standard investigations or treatment. In fact, there is lack of evidence in follow up in abortion care in general. The NICE guideline (6) as well as the best practice in abortion care provided by the college (7) did not provide specific guidance regarding symptoms and signs for incomplete abortion especially post mid-trimester abortion. There is also lack of guidance on how to investigate suspected incomplete abortion. With the current situation where more than 70% of abortion is done in the private sectors, (6) it is understandably difficult to follow such patients up and to communicate with the primary and secondary care providers regarding the treatments they have gone through. However, as retained fetal tissue and bones can cause a number of menstrual as well as fertility problems in ladies, it is important to obtain a detailed obstetric history including abortion and bear in mind such differential diagnosis. There is also a need to review the current guideline to provide guidance in terms of early recognition, investigation and appropriate treatment and follow up to these women, especially when abortion rate is on the rise with current pandemic. (8)
References
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  2. Gainder S, Arora P, Dhaliwal LK. Retained Intrauterine Bony Fragments as a Cause of Secondary Infertility in a Tertiary Level Indian Hospital. J Hum Reprod Sci. 2018 Jul-Sep;11(3):286-290. doi: 10.4103/jhrs.JHRS_33_18. PMID: 30568360; PMCID: PMC6262664.
  3. Gulec UK, Parlakgumus HA, Kiliçdag EB, Bolat F, Bagis T. Osseous metaplasia of the endometrium. BMJ Case Rep. 2010 Aug 19;2010:bcr0420102931. doi: 10.1136/bcr.04.2010.2931. PMID: 22766572; PMCID: PMC3029676.
  4. Mishra N, Bharti R, Mittal P, Suri J, Pandey D. Retained Intra-uterine Foetal Bones Resulting in Secondary Infertility: A Case Report. Cureus. 2018 May 3;10(5):e2575. doi: 10.7759/cureus.2575. PMID: 31489270; PMCID: PMC6710494.
  5. Verma U, Chong D, Perez I, Medina C. Fetal bones retained in the uterine cavity as a rare cause of chronic pelvic pain: a case report. J Reprod Med. 2004 Oct;49(10):853-5. PMID: 15568412.
  6. NICE guideline on abortion care
  7. Best practice in abortion care RCOG
  8. Abortion statistics for England and Wales during the COVID-19 pandemic - GOV.UK (www.gov.uk)