SOGC CLINICAL PRACTICE GUIDELINE| Volume 43, ISSUE 5, P614-630.e1, May 2021

Guideline No. 414: Management of Pregnancy of Unknown Location and Tubal and Nontubal Ectopic Pregnancies

Published:January 13, 2021DOI:



      To provide an evidence-based algorithm to guide the diagnosis and management of pregnancy of unknown location and tubal and nontubal ectopic pregnancy.

      Target Population

      All patients of reproductive age.

      Benefits, Harms, and Costs

      The implementation of this guideline aims to benefit patients with positive β-human chorionic gonadotropin results and provide physicians with a standard algorithm for expectant, medical, and surgical treatment of pregnancy of unknown location and tubal pregnancy and nontubal ectopic pregnancies.


      The following search terms were entered into PubMed/Medline and Cochrane in 2018: cesarean section, chorionic gonadotropin, beta subunit, human/blood, fallopian tubes/surgery, female, fertility, humans, infertility, laparoscopy, methotrexate, methotrexate/administration & dosage, methotrexate/therapeutic use, pregnancy (abdominal, angular, cervix, cornual, ectopic, ectopic/diagnosis, ectopic/diagnostic imaging, ectopic/drug therapy, ectopic/epidemiology, ectopic/mortality, ectopic/surgery, heterotopic, interstitial, isthmo-cervical, ovarian, tubal, unknown location), recurrence, risk factors, salpingectomy, salpingostomy, tubal pregnancy, ultrasonography, doppler ultrasonography, and prenatal. Articles included were randomized controlled trials, meta-analyses, systematic reviews, observational studies, and case reports. Additional publications were identified from the bibliographies of these articles. Only English-language articles were reviewed.

      Validation Methods

      The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and weak recommendations).

      Intended Audience

      Obstetrician–gynaecologists, family physicians, emergency physicians, midwives, registered nurses, nurse practitioners, medical students, and residents and fellows.

      SUMMARY STATEMENTS (GRADE ratings in parentheses)

      • 1
        Ectopic pregnancies account for the majority of first-trimester maternal deaths (high).
      • 2
        Tubal pregnancies account for the majority of ectopic pregnancies (high).
      • 3
        Pregnancy of unknown location is a transient state in the diagnostic process, leading to a final diagnosis of viable or nonviable intrauterine pregnancy, ectopic pregnancy, or persistent pregnancy of unknown location (high).
      • 4
        Management protocols for pregnancy of unknown location are predictive and not diagnostic. They are formulated to risk stratify pregnancy of unknown location as either high or low risk for ectopic pregnancy (high).
      • 5
        Methotrexate is a safe and effective treatment for carefully selected tubal and nontubal ectopic pregnancies (high).
      • 6
        Expectant management of a tubal pregnancy can eliminate medication-related and surgical risks in carefully selected patients. However, expectant management can result in serious morbidity if it fails (low).
      • 7
        There is no evidence to recommend conservative, tube-sparing salpingotomy over salpingectomy in the surgical management of the majority of tubal pregnancies (moderate).
      • 8
        Ultrasound diagnosis of nontubal ectopic pregnancy requires experienced sonographers and radiologists (moderate).
      • 9
        Providers should have a high index of suspicion for cervical ectopic pregnancy because severe outcomes often occur with delayed diagnosis and management (low).
      • 10
        Women who will be undergoing treatment for a cervical pregnancy should be counselled about the risk of hemorrhage and the possible need for hysterectomy (low).
      • 11
        The terms interstitial and cornual pregnancy are used interchangeably in the literature (low).
      • 12
        Abdominal pregnancies are associated with high rates of maternal mortality owing to the high risk of catastrophic hemorrhage (low).
      • 13
        Laparoscopy is often required for definitive diagnosis of ovarian pregnancy (very low).
      • 14
        Spontaneous heterotopic pregnancies are rare (low).

      RECOMMENDATIONS (GRADE ratings in parentheses)

      • 1
        We recommend the use of risk models (e.g., the M6 model) to stratify pregnancy of unknown location as either high or low risk for ectopic pregnancy to guide treatment decisions (strong, moderate).
      • Tubal Pregnancies
      • 2
        Clinicians can consider expectant management and very close follow-up in carefully selected patients with early, asymptomatic tubal pregnancies (conditional, low).
      • 3
        If a patient meets the criteria for medical management of a tubal pregnancy, we suggest the single- or double-dose methotrexate protocol (conditional, moderate).
      • 4
        If feasible, clinicians should use a minimally invasive approach in the surgical management of tubal pregnancy (strong, high).
      • 5
        Consider both patient and surgeon factors when deciding between salpingectomy and salpingotomy; there is no evidence to recommend conservative, tube-sparing salpingotomy over salpingectomy when the contralateral fallopian tube is normal (conditional, low).
      • Cesarean Scar Pregnancies
      • 6
        Clinicians should consider medical management with multidose and/or local methotrexate as a safe and effective treatment in appropriately selected women with a cesarean scar pregnancy (conditional, moderate).
      • 7
        Clinicians should consider treating type I cesarean scar pregnancies surgically with hysteroscopy (conditional, low).
      • 8
        Clinicians should consider treating type II cesarean scar pregnancies surgically with laparoscopy (conditional, low).
      • Cervical Pregnancies
      • 9
        In appropriately selected cervical pregnancies, clinicians should offer medical management over surgical management with dilatation and curettage (conditional, low).
      • Interstitial/Cornual Pregnancies
      • 10
        Clinicians should offer conservative medical management with multidose and/or local methotrexate for interstitial or cornual pregnancies in appropriately selected patients (conditional, moderate).
      • 11
        If surgery is required, clinicians may perform either laparoscopic cornuotomy or cornual wedge resection because both procedures have comparable results (conditional, low).
      • Abdominal Pregnancies
      • 12
        Clinicians may choose either laparotomy or laparoscopy to excise an abdominal pregnancy (conditional, low).
      • Ovarian Pregnancies
      • 13
        Clinicians may offer conservative medical management of ovarian pregnancies with methotrexate in appropriately selected patients (conditional, low).
      • 14
        Clinicians can perform laparoscopic ovarian wedge resection rather than oophorectomy for ovarian ectopic pregnancies, if clinically appropriate (conditional, low).
      • Heterotopic Pregnancies
      • 15
        Clinicians should not offer systemic methotrexate in the presence of a desired intrauterine pregnancy (conditional, moderate).
      • 16
        We suggest surgical excision of the ectopic pregnancy in cases of heterotopic pregnancy. If the intrauterine pregnancy is not desired, we conditionally recommend adding dilatation and curettage to the surgical procedure to evacuate the uterine cavity (conditional, moderate).



      β-hCG (β-human chorionic gonadotropin), IUP (Intrauterine pregnancy), MA (Medical abortion), PUL (Pregnancy of unknown location)
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