A heterotopic pregnancy involving a caesarean section scar

Ultrasound-guided procedures in the management of heterotopic caesarean scar pregnancy - A review of case reports and case series

Background

Heterotopic caesarean scar pregnancy (HCSP) is where one gestational sac implants in the previous caesarean section (CS) scar and another sac implants in the uterine cavity. There is limited evidence on the management of this rare condition. Here, we present a case of HCSP in which US-guided selective reduction of the CS pregnancy (CSP) was performed using potassium chloride (KCl) to salvage the intrauterine pregnancy. We also conducted a review of published case reports to understand the determinants of outcome.

Methods

After a MEDLINE search, 23 case reports were found eligible based on quality assessment and were included in the analysis. A composite-score indicating overall obstetric morbidity was computed, and mixed-effects linear regression was implemented to identify its predictors.

Results

US-guided local treatment was the most common mode of intervention for HCSP. The regression analyses revealed that the poor obstetric outcomes, especially antepartum haemorrhage (APH) and postpartum haemorrhage (PPH), were significantly predicted by advanced gestational age at treatment and a higher number of previous CS, irrespective of the mode of treatment.

Conclusion

These results indicate that a high index of suspicion for an early ultrasound diagnosis and treatment is critical. US-guided techniques are useful in salvaging the intrauterine pregnancy with decreased maternal morbidity. The results are preliminary due to the rarity and a small number of published reports. Every CSP should be recorded in a central international registry to obtain reliable data on the diagnosis and management of women with CSP. Given the rising rates of CS, future systematic studies are warranted.

Early intervention for heterotopic caesarean scar pregnancy to preserve intrauterine pregnancy may improve outcomes: a retrospective cohort study

RESEARCH QUESTION

What is the best intervention time and method for patients who are diagnosed with heterotopic caesarean scar pregnancy (HCSP) wishing to preserve intrauterine pregnancy.

DESIGN

Four patients diagnosed with HCSP from January 2014 to May 2019 were enrolled. Because HCSP is rare, data on 27 published cases were extracted to augment the analysis. Clinical characteristics and medical documents related to fetal reduction and subsequent maternal-neonate outcomes were analysed.

RESULTS

The intervention time was significantly earlier in the full-term birth group (6.76 ± 1.05 weeks) compared with pre-term birth group (8.02 ± 1.55 weeks; P = 0.042). The cumulative full-term delivery rate was 91.48% when the intervention was at 6 weeks' gestation and decreased to 42.02% at 8 weeks. The maternal-neonate outcome was similar among the selective fetal reduction and surgical removal groups as was delivery time (34.68 ± 3.12 versus 34.80 ± 6.64 weeks; P = 0.955). In the four cases undergoing selective fetal reduction, the residual mass grew by 1.16-7.07 times compared with the area before reduction. The maximum size of the residual mass was observed at 12-13 weeks and 22-25 weeks.

CONCLUSIONS

Most patients with HCSP who choose to keep intrauterine pregnancy will be able to carry the fetus to term. Selective fetal reduction would be the first intervention of choice and should take place immediately after diagnosis. The residual mass after reduction could continue to grow throughout the whole pregnancy, although this should not be considered as an indication for termination. With good supervision and careful management, the pregnancy could be maintained and carried to term.