Outcome of Cesarean scar pregnancy managed expectantly: systematic review and meta-analysis.

OBJECTIVE: To explore the outcome in women managed expectantly following the diagnosis of Cesarean scar pregnancy (CSP).

METHODS: An electronic search of MEDLINE, EMBASE and ClinicalTrials.gov databases was performed utilizing combinations of relevant medical subject headings for 'Cesarean scar pregnancy' and 'outcome'. Reference lists of relevant articles and reviews were hand-searched for additional reports. Observed outcomes included: severe first-trimester vaginal bleeding; clinical symptoms (abdominal pain, vaginal bleeding) requiring treatment; uncomplicated miscarriage; complicated miscarriage requiring intervention; first- or second-trimester uterine rupture or hysterectomy; third-trimester bleeding, uterine rupture or hysterectomy; maternal death; incidence of abnormally invasive placenta (AIP); prevalence of placenta percreta; ultrasound signs suggestive of AIP; and live birth. Meta-analyses of proportions using a random-effects model were used to combine data. Cases were stratified based on the presence or absence of embryonic/fetal heart activity at the time of diagnosis.

RESULTS: A total of 17 studies (69 cases of CSP managed expectantly, 52 with and 17 without embryonic/fetal heart beat) were included. In women with CSP and embryonic/fetal heart activity, 13.0% (95% CI, 3.8-26.7%) experienced an uncomplicated miscarriage, while 20.0% (95% CI, 7.1-37.4%) required medical intervention. Uterine rupture during the first or second trimester of pregnancy occurred in 9.9% (95% CI, 2.9-20.4%) of cases, while hysterectomy was required in 15.2% (95% CI, 3.6-32.8%) of all cases. Forty (76.9% (95% CI, 65.4-86.5%)) women progressed to the third trimester of pregnancy, of whom 39.2% (95% CI, 15.4-66.2%) experienced severe bleeding. Finally, 74.8% (95% CI, 52.0-92.1%) had a surgical or pathological diagnosis of AIP at delivery and around two-thirds (69.7% (95% CI, 42.8-90.1%)) of them had placenta percreta. In women with CSP but no embryonic/fetal cardiac activity, an uncomplicated miscarriage occurred in 69.1% (95% CI, 47.4-87.1%) of cases, while surgical or medical intervention during or immediately after miscarriage was required in 30.9% (95% CI, 12.9-52.6%). Uterine rupture during the first trimester of pregnancy occurred in 13.4% (95% CI, 2.7-30.3%) of cases, but hysterectomy was not required in any case.

CONCLUSIONS: CSP with positive embryonic/fetal heart activity managed expectantly is associated with a high burden of maternal morbidity including severe hemorrhage, early uterine rupture, hysterectomy and severe AIP. Despite this, a significant proportion of pregnancies complicated by CSP may progress to, or close to, term, thus questioning whether termination of pregnancy should be the only therapeutic option offered to these women. Expectant management of CSP with no cardiac activity may be a reasonable option in view of the low likelihood of maternal complications requiring intervention, although close surveillance is advisable to avoid adverse maternal outcome. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.