Interstitial pregnancy management: A multicentric analysis of 98 patients from the FRANCOGENT group comparing surgery and medical treatment

OBJECTIVE

To evaluate the outcomes associated with each therapeutic option for patients diagnosed with interstitial pregnancy (IP).

METHODS

We conducted a multicentric retrospective cohort study within the departments of Gynecology and Obstetrics involved in the Francogent research group. Women treated for an interstitial pregnancy between January 2008 to December 2019 were included. Three therapeutic options were evaluated: surgical treatment (ST); in situ methotrexate combined with systemic methotrexate (IS-MTX); and systemic methotrexate (IM-MTX). Success of first-line treatment was defined by hCG negativation (<5I U/L). Secondary outcomes included the need for secondary surgical procedure, secondary medical treatment, emergency surgery, postoperative complications, duration of hospitalization, and delay before hCG negativation.

RESULTS

A total of 98 patients were managed for IP: 42 (42.9%) patients had IM-MTX; 34 (34.7%) had IS-MTX; and 22 (22.4%) had ST. First-line treatment was successful in all patients of the ST group (22/22, 100%), in 31% of patients within the IM-MTX group (13/42) and 70.6% (24/34) in the IS-MTX group. The sole parameter associated with the risk of treatment failure was the mode of methotrexate administration. The size of the gestational sac or the presence of fetal heartbeat was not associated with decreased medical treatment (IS or IM-MTX) efficiency.

CONCLUSION

Either ST or IS-MTX are good options for IP treatment associated with high success rates. A single-dose regimen of IM-MTX is less efficient than IS-MTX or ST. Symptomatic patients with severity criteria should always undergo emergency surgery. IP remains a high-risk condition that should be managed, whenever possible, in referral centers to potentialize the chances of favorable outcomes.

Interstitial ectopic pregnancy successfully treated with methotrexate

An ectopic pregnancy (EP) occurs when the fertilised ovum implants outside the endometrial cavity. An EP has an incidence of 1%, with the majority occurring in the fallopian tube. It has a maternal mortality of 0.2 per 1000, with about two-thirds of these deaths associated with substandard care. An interstitial pregnancy occurs when the EP implants in the interstitial part of the fallopian tube. An interstitial ectopic pregnancy (IEP) shows few early clinical symptoms, hence it is associated with serious or fatal bleeding and a mortality rate up to 2.5%. With the advent of transvaginal ultrasound scan (TV USS), correlated with serum beta human chorionic gonadotropin (BHCG) assay, earlier diagnosis of an EP can be established. An EP is often diagnosed in women who are trying to conceive; therefore, the prognosis of future fertility is one of the main concerns associated with this diagnosis. Management can be surgical, expectant or medical with methotrexate (MTX). However, the best approach is tailored to the woman's individual case. The authors present the case of a primigravida woman presenting with abdominal pain and vaginal bleeding at 6 weeks gestation following assisted reproduction. Her BHCG showed a suboptimal rise. Her TV USS showed no evidence of an intrauterine pregnancy. There was no evidence of an adnexal mass or free fluid. As her BHCG remained static, she underwent a diagnostic laparoscopy. A right sided IEP was identified. Due to the high risk of bleeding requiring transfusion or hysterectomy and her desire to preserve her fertility, she received medical management with MTX. Indeed, research has shown that women successfully managed expectantly achieve better reproductive outcomes, with the shortest time to achieve a subsequent intrauterine pregnancy. This case acts as a cautionary reminder of the challenges associated with identifying an IEP on TV USS. A high index of clinical suspicion is required to prevent maternal morbidity and mortality.

Interstitial Pregnancy Treated with Mifepristone and Methotrexate with High Serum β-hCG Level in a Patient Wishing to Preserve Fertility: Time to Define Standardized Criteria for Medical/Surgical Therapy?

Interstitial pregnancy (IP) accounts for 2% of all ectopic pregnancies and has a mortality rate of 2-2.5%. The diagnosis is made by a transvaginal ultrasound and the treatment can be medical or surgical. We report the case of a 36-year-old primigravida who was 6 + 5 weeks pregnant, diagnosed with interstitial pregnancy by ultrasound, who had a very high serum β-hCG level (31,298 mIU/mL) and wanted to preserve her fertility. The patient was treated with one dose of mifepristone and a double dose of methotrexate since the decrease in the β-hCG serum level was less than 15% after the first dose. At the beginning, medical therapy was effective, as no embryonal cardiac activity was detected and serum β-hCG levels decreased early, but on the 20th day of hospitalization, the patient underwent surgery for her clinical symptoms and the evidence of free fluid in the Douglas pouch at a transvaginal ultrasound exam. Our experience showed that medical treatment should be considered, especially in women wishing to preserve their fertility. Further studies are needed to establish a standardized protocol and maybe a clinical score that can be useful in predicting the patients in which medical therapy could be most successful.

Successful transvaginal aspiration of interstitial pregnancy after failed methotrexate treatment

Interstitial pregnancy is an uncommon condition that is challenging, not only in making an accurate diagnosis, but also in the choice of treatment. Systemic methotrexate (MTX) treatment has been favored to prevent scarring of the uterus. Nevertheless, surgery is generally indicated when this treatment fails. Transvaginal aspiration of the gestational tissue has been proposed as an alternative to surgery. The authors present a case of interstitial pregnancy in which the patient failed to respond to multidose MTX treatment and was successfully treated with transvaginal sonography-guided transvaginal aspiration of the gestational tissue, thereby bypassing the risk associated with undergoing major surgery. Transvaginal aspiration of conceptive tissue may be a novel treatment for patients with unruptured interstitial pregnancy.

Transabdominal ultrasound-guided injection of methotrexate in the treatment of ectopic interstitial pregnancies

PURPOSE

In a retrospective observational study, we evaluated the feasibility and safety of medical therapy with transabdominal ultrasound-guided injection of methotrexate (MTX) into the gestational sac (GS) in patients with interstitial ectopic pregnancies.

METHODS

Fourteen interstitial ectopic pregnancies were treated with transabdominal ultrasound-guided injection of MTX (25 mg). All patients were hemodynamically stable. In all patients, the 10-cm distance between the GS and vaginal fornices was ≥10 cm, making transvaginal injection difficult. To evaluate feasibility and safety of the procedure, we assessed complications clinically and with imaging during a 1-year follow-up.

RESULTS

In all 14 patients, MTX injected locally into the GS successfully terminated the interstitial pregnancy, thereby avoiding surgery. There was no complications during follow-up.

CONCLUSIONS

The successful outcome in our patients suggests that the transabdominal route is feasible and safe as a nonsurgical option for terminating an ectopic interstitial pregnancy in patients in whom the transvaginal route is contraindicated or difficult, provided the patients are properly selected and operators have sufficient experience with the technique.