Live normally sited pregnancy with concurrent residual tubal ectopic pregnancy: A case report.

A fit and well 28-year-old woman, in her second pregnancy (previous termination of pregnancy), presented to the emergency department with a two-day history of vaginal bleeding and a positive pregnancy test. She was 8 weeks pregnant according to her last menstrual period (LMP). TVUS showed a right tubal EP with no hemoperitoneum ( Fig. 1 ) and her initial serum β-hCG level was 251.5 IU/L. Following counselling, she opted for expectant management. Subsequent β-hCG levels are shown in Table 1 . Fig. 1 Transvaginal ultrasound scan in the axial plane, performed using A-mode. Initial scan performed at first presentation showing the right tubal ectopic pregnancy (white arrow). Fig. 1 Table 1 A table showing the respective serum b-hCG levels (IU/L) on the days following first presentation of the ectopic pregnancy. Table 1 Days from first presentation Serum b-HCG level (IU/L) Day 0 251.5 Day 2 527.5 Day 4 487.4 Day 6 687.5 Day 8 607.2 Day 12 360.3 Day 14 265.1 Day 21 68.3 Day 28 16.7 Day 34 4.1 Transvaginal ultrasound scan in the axial plane, performed using A-mode. Initial scan performed at first presentation showing the right tubal ectopic pregnancy (white arrow). A table showing the respective serum b-hCG levels (IU/L) on the days following first presentation of the ectopic pregnancy. As per unit protocol, two weeks following a negative pregnancy test, a repeat TVUS was performed to check for resolution of EP, which showed a residual right tubal EP. She was advised to use effective contraception and two further fortnightly TVUS scans were arranged, which showed the previously seen residual right tubal EP unchanged in size. She re-presented to the early pregnancy unit (EPU) with a positive pregnancy test 13 weeks following her negative pregnancy test (124 days from initial presentation). She was 4 weeks +5 days pregnant according to her LMP. On TVUS, the residual EP mass was again noted ( Fig. 2 ) and a concurrent early normally sited pregnancy ( Fig. 3 ) with a corpus luteum on the left. Fig. 2 Transvaginal ultrasound scan in the axial plane, performed using A-mode. Day 124 from initial presentation of the ectopic pregnancy. The right residual ectopic pregnancy can be seen (white arrow) and is measured to be 8 mm × 8 mm × 7 mm. Fig. 2 Fig. 3 Transvaginal ultrasound scan in the axial plane, performed using A-mode. Day 125 from initial presentation of the ectopic pregnancy. Gestational age estimated to be 4 weeks and 6 days. The scan shows a small normally sited sac (white arrow) measured to be 7 mm × 5 mm × 8 mm in the top left of the uterine cavity. Fig. 3 Transvaginal ultrasound scan in the axial plane, performed using A-mode. Day 124 from initial presentation of the ectopic pregnancy. The right residual ectopic pregnancy can be seen (white arrow) and is measured to be 8 mm × 8 mm × 7 mm. Transvaginal ultrasound scan in the axial plane, performed using A-mode. Day 125 from initial presentation of the ectopic pregnancy. Gestational age estimated to be 4 weeks and 6 days. The scan shows a small normally sited sac (white arrow) measured to be 7 mm × 5 mm × 8 mm in the top left of the uterine cavity. Due to uncertainty surrounding how the now increasing serum β-hCG levels would affect the residual EP, she was followed up with fortnightly scans. The normally sited pregnancy continued to develop normally as expected, whilst the residual EP mass remained stable in size ( Fig. 4 ). Fig. 4 Line graph showing the size (measured as volume on TVUS) of the ectopic pregnancy from the first presentation up until physical resolution. The green dashed line indicates the time point of biochemical resolution (negative serum β-hCG) of the ectopic pregnancy, which was at day 28 from first presentation. Of note, there is no data point for day 182 as the ectopic pregnancy was no longer visible on TVUS. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) Fig. 4 Line graph showing the size (measured as volume on TVUS) of the ectopic pregnancy from the first presentation up until physical resolution. The green dashed line indicates the time point of biochemical resolution (negative serum β-hCG) of the ectopic pregnancy, which was at day 28 from first presentation. Of note, there is no data point for day 182 as the ectopic pregnancy was no longer visible on TVUS. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) At 22 weeks after the negative pregnancy test (182 days from initial presentation), the residual EP was no longer identifiable on TVUS. At this point, the live normally sited pregnancy was 13 weeks, and the patient was subsequently discharged from the EPU. She continued her pregnancy to full term and delivered a healthy baby. A timeline of the case is given in Fig. 5 . Fig. 5 A timeline of key findings during the case, from initial presentation of the ectopic pregnancy at day 0 to physical resolution of the residual ectopic pregnancy at day 182. Fig. 5 A timeline of key findings during the case, from initial presentation of the ectopic pregnancy at day 0 to physical resolution of the residual ectopic pregnancy at day 182.

No funding from an external source supported the publication of this case report.

Written informed consent was obtained from the patient for publication of the case report and accompanying images.

Even though expectant management of EP is considered successful once biochemical resolution is achieved (b-hCG < 20 IU/L), physical resolution often takes longer. This case report demonstrates that a normally sited pregnancy can develop in the presence of a residual EP, whilst rising β-hCG levels from the newly conceived pregnancy have no effect on size and resolution of the residual EP.

In the UK, although most tubal EPs are managed surgically [ 2 ], studies report success rates of expectant management to be 57–100 % [ 3 ]. For expectant management, the guidelines from the National Institute for Health and Care Excellence (NICE) [ 10 ] state b-hCG levels should be measured on days 2, 4 and 7 after the original test, and if levels decrease by ≥15 % from the previous value, testing should be repeated weekly until negative (< 20 IU/L). b-hCG has been shown to be a good biomarker to monitor resolution of EPs managed expectantly [ 4 ]. Mavrelos et al. [ 11 ] showed b-hCG resolution with expectant management typically takes just under 3 weeks. In this case, biochemical resolution of EP (defined as b-hCG < 20 IU/L) took 28 days, whilst sonographic resolution of the residual EP was achieved after 182 days. Dooley et al. [ 12 ] found physical resolution often takes longer than biochemical resolution, with 4.5 % of cases taking over 78 days for physical resolution, and therefore concluded negative b-hCG levels may not be a suitable end-point for expectantly managed EPs. In the literature, residual EP is sometimes termed ‘chronic EP’; however, the European Society of Human Reproduction and Embryology (ESHRE) advises against using the latter in clinical practice and defines residual EP as any EP presenting as a discrete mass on ultrasound in the presence of a negative pregnancy test [ 1 ]. Residual EPs can cause abdominal pain, abnormal vaginal bleeding and amenorrhoea, often requiring surgical management [ 6 ]. Cases of ruptured residual EPs have also been reported [ 8 , 9 ], highlighting potential life-threatening sequalae. A systematic review of residual EP by Tempfer et al. [ 5 ] presents common symptoms and treatment outcomes; however, there are no documented cases of a concurrent live normally sited pregnancy. Due to its clinical rarity, it is difficult to understand the relationship between a residual EP and a concurrent live normally sited pregnancy and potential risks. In the present case, the co-existence of the residual EP and normally sited pregnancy did not affect the size of the residual EP nor the development of the live normally sited pregnancy. Although studies show 50–80 % of women with EP, irrespective of management method, subsequently have successful pregnancies [ 13 ], recommendations on a safe pregnancy interval are limited. The RCOG guidelines recommend a three-month interval following medically managed EPs due to concerns of effects of methotrexate on fetal development [ 2 ] but there is no clear guidance for women managed expectantly. Given the time discrepancy between biochemical and physical resolution of EP and the potential adverse risks of residual EP, further research is needed to determine when women with expectantly managed EP can safely conceive again. This case report demonstrates a unique presentation of a concurrent residual EP and live normally sited pregnancy, which adds valuable insight to the limited literature on residual EP. Another strength of this study is the bimodal approach to monitoring resolution of EP through serum b-hCG levels (biochemical) and transvaginal ultrasound (physical). Owing to the rarity of this case, generalisability of the outcomes is limited and further research into potential adverse effects is needed. Although physical resolution of the residual EP was determined by ultrasonographic imaging, it is difficult to ascertain complete resolution without further investigations into the patency of the affected fallopian tube and future pregnancy outcomes.

This article was not commissioned and was peer reviewed.

Kathleen Mejia contributed to acquiring and interpreting the data, drafting the manuscript, undertaking the literature review and revising the article critically for important intellectual content. Tara Ajith contributed to patient care, interpreting the data, and drafting and revising the article critically for important intellectual content. Maria Memtsa contributed to patient care, conception of the case report, interpreting the data and revising the article critically for important intellectual content. Emma Kirk contributed to patient care, interpreting the data and revising the article critically for important intellectual content. All authors approved the final submitted manuscript.

An ectopic pregnancy (EP) is one that occurs outside the uterine cavity, most commonly in the fallopian tubes (tubal EP) [ 1 ]. Untreated or misdiagnosed EP can be life-threatening; therefore it is imperative that it is diagnosed promptly and appropriate management is undertaken. The imaging modality of choice for diagnosing an EP is transvaginal ultrasound (TVUS). Dependent on multiple factors – including clinical status, symptoms, and patient choice - EPs can be managed expectantly, medically with methotrexate or surgically via salpingectomy or salpingotomy. The guidelines from the UK Royal College of Obstetricians and Gynaecologists (RCOG) state expectant management is suitable for clinically stable patients with an EP confirmed on TVUS and an initial level of beta human chorionic gonadotropin (β-hCG) <1500 IU/L [ 2 ], and has a success rate of 57–100 % [ 3 ]. Serum β-hCG levels are used to monitor patients undergoing expectant management and are a key indicator of successful treatment [ 4 ]. A residual EP is one that is visible as a discrete mass on ultrasound in the presence of a negative pregnancy test [ 1 ]; residual EPs account for 6–20 % of all EPs [ 5 , 6 ]. Most are asymptomatic but they can present with abdominal pain and can even mimic other pathologies such as pelvic malignancy, pelvic inflammatory disease, fibroids and endometriosis [ 6 , 7 ]. Accurate diagnosis of residual EP is important as adverse consequences can include tubal rupture and haemorrhage [ 8 , 9 ]. This report concerns the case of a woman who presented with a concurrent live normally sited pregnancy in the presence of a residual EP. It appears to be the first reported case of its kind.

The authors declare that they have no competing interest regarding the publication of this case report.