A Shocking Case of Retained Products

Case Presentation

A 22 year old G1P0010 female presented to the Emergency Department (ED) with vaginal bleeding and an episode of syncope. She started bleeding ten days ago after receiving mifepristone for a missed abortion (estimated gestational age of 10 weeks and 6 days). She continued to bleed intermittently so she was also given misoprostol. On the day of her ED visit, she syncopized while in the bathtub and was still having vaginal bleeding despite the misoprostol.

Upon her arrival to the ED, her initial vitals were: blood pressure of 84/43, heart rate of 172, respiratory rate of 25, with an oxygen saturation of 97% on room air, and a temperature of 38.2 C. On physical exam, she was disoriented and appeared pale and diaphoretic. She was also noted to have active vaginal bleeding with golf-ball sized clots. The differential of her hypotension included hemorrhagic shock versus septic shock from possible retained products of conception (RPOC).

Point-of-care ultrasound was performed and revealed a hyperechoic, heterogeneous mass in the uterus with a thickened endometrial stripe, concerning for RPOC (Figure 1). There was no free fluid visualized and the endometrium was not hypervascular on color Doppler (Figure 2). Obstetrics Gynecology (OB Gyn) was consulted for definitive management. The patient was treated with empiric antibiotics and was given intravenous fluids as well as blood products. She was emergently taken to the operating room (OR) with OB Gyn for a dilation & curettage (D&C). The surgical specimen sent from the D&C showed decidua and immature placenta, confirming the diagnosis of RPOC.

Discussions

Retained products of conception are a complication of roughly 1% of term pregnancies, with an even higher rate for miscarriages and terminated pregnancies (up to 6% and 15% respectively).^1,2 Miscarriages are extremely common, affecting about 10% – 28% of pregnancies.³ Additionally, the prevalence of legally terminated pregnancies in the United States is estimated to be over 620,000 per 2021 CDC statistics.⁴

RPOC can be managed conservatively, medically, or surgically. If untreated, short and long-term risks of RPOC include infection and prolonged bleeding with a risk of progressing to hemorrhagic and/or septic shock.^1,3,5 The gold standard of treatment is surgical intervention with D&C. However, this carries the risk of causing intrauterine adhesions, infertility, cervical injury, and uterine perforation.^1-3,5,6 Thus, conservative and medical management are usually first line even if it is not always effective.

With these risks of both treatment and non-treatment, the accurate diagnosis of RPOC is imperative. Yet, its diagnosis is often challenging. Clinically, RPOC is suspected when the patient presents with prolonged vaginal bleeding (> 2 weeks), abdominal pain, and/or fever in the setting of a recent pregnancy or miscarriage.³ To confirm the diagnosis, transvaginal ultrasound (TVUS) is typically used.3 Sonographic findings of RPOC include an echogenic mass, a thickened endometrial stripe, and the presence of hypervascularity in the endometrium on Color Doppler.^2,5,6 The echogenic mass has been described as a “hyperechoic material” or “an irregular, mixed echogenic endometrium,” and the endometrial thickness cutoff used most often in the literature is 10-15 mm.^2,3,6

However, there is no gold standard yet established in the literature. Previous publications have attempted to do so however the description, sensitivity, and specificity of each ultrasound finding is variable with different cutoffs used in different manuscripts. Additionally, a thickened endometrial stripe and complex endometrial fluid can be findings of normal postpartum ultrasound findings.⁵ The most recently published 2023 meta-analysis found that an echogenic mass is the most sensitive and specific finding of RPOC (89.7% and 86.8% respectively). ² An endometrial thickness of over 10mm has a sensitivity of 66.7% with a specificity of 86.6% and the color Doppler findings have a sensitivity and specificity of 82.1% and 44.2% respectively.² In their conclusion, they recommend using all three sonographic findings to increase both specificity and sensitivity of the sonographic diagnosis.

Case Conclusion

The patient was started on vasopressors while in the OR and was moved to the intensive care unit (ICU) overnight. She was quickly weaned off pressors and was extubated by the following day. She was transitioned to oral antibiotics and discharged by postoperative day 3. She followed up with OB Gyn at an outpatient clinic and had no further complications.

Indications

• Fever
• Hypotension
• Lower abdominal pain
• Miscarriage
• Pregnancy
• Vaginal bleeding

Pitfalls and Limitations

• A thickening endometrial stripe and complex endometrial fluid can be normal postpartum ultrasound findings
• Additional research needs to be performed to confirm a gold standard cutoff and sonographic diagnosis of RPOC
• Use both clinical and sonographic findings for the diagnosis of RPOC

References

• Hooker AB, Aydin H, Brölmann HA, et al. Long-term complications and reproductive outcome after the management of retained products of conception: a systematic review. Fertil Steril 2016;105(1):156-64.e1-2, doi:10.1016/j.fertnstert.2015.09.021
• Sundararajan S, Roy S, Polanski LT. The accuracy of ultrasound scan in diagnosing retained products of conception: a systematic review and meta-analysis. Am J Obstet Gynecol 2023, doi:10.1016/j.ajog.2023.11.1243
• Hamel CC, van Wessel S, Carnegy A, et al. Diagnostic criteria for retained products of conception-A scoping review. Acta Obstet Gynecol Scand 2021;100(12):2135-2143, doi:10.1111/aogs.14229
• Kortsmit K, Nguyen AT, Mandel MG, et al. Abortion Surveillance – United States, 2021. MMWR Surveill Summ 2023;72(9):1-29, doi:10.15585/mmwr. ss7209a1
• Steinkeler J, Coldwell BJ, Warner MA. Ultrasound of the postpartum uterus. Ultrasound Q 2012;28(2):97-103, doi:10.1097/RUQ.0b013e31824e6b7d
• De Winter J, De Raedemaecker H, Muys J, et al. The value of postpartum ultrasound for the diagnosis of retained products of conception: A systematic review. Facts Views Vis Obgyn 2017;9(4):207-216