[Medical treatment of ectopic pregnancy: a randomized clinical trial comparing metotrexate-mifepristone and methotrexate-placebo]

Interstitial Ectopic Pregnancy: The Role of Mifepristone in the Medical Treatment

Interstitial pregnancy is defined as the presence of a gestational sac in the most proximal section of the fallopian tube. Management of interstitial pregnancy remains a debated topic. Depending on hemodynamic stability, size of pregnancy, depth of surrounding myometrium, and desires for future fertility, interstitial pregnancy can be managed medically or surgically. We reviewed the literature in December 2020 using keywords “interstitial pregnancy”, “medical treatment”, “methotrexate”, and “mifepristone”. Articles published from January 1991 until 2020 were obtained from databases EMBASE, SCOPUS, and PUBMED. We describe the case of a patient with an interstitial pregnancy that was managed with a total medical approach in August 2020 at Burlo Garofolo Hospital. The patient was asymptomatic and hemodynamically stable, with a high level of serum β-hCG (22,272 mUi/mL). We used the combination of methotrexate (MTX) and mifepristone. Medical therapy was effective leading to interstitial pregnancy resolution in 51 days without collateral effects for the patient. We found seven previous cases reported in the literature. Our purpose is to underline the efficacy of medical therapy with systemic multidose MTX associated with a single oral dose of mifepristone and also folinic acid when is present a viable fetus and a high serum β-hCG level.

Conservative Treatment of Interstitial Ectopic Pregnancy with the Combination of Mifepristone and Methotrexate: Our Experience and Review of the Literature

Introduction

Interstitial pregnancy (IP) is an ectopic pregnancy (EP) located in the portion of the fallopian tube that penetrates the uterine muscular layer. Incidence increased in the last two decades with the widespread use of the assisted reproductive techniques. It is estimated in 1-6% of all the EPs, with a maternal mortality rate of 2.0-2.5%. Clinical presentation, gestational age at diagnosis, beta-human chorionic gonadotropin (β-hCG) levels, ultrasound features, and patient preference, should be considered to determine the best management: surgical, medical treatment, or close observation. We report two cases of IP successfully managed with systemic MTX and Mifepristone: in one case β-hCG was >10.000 mIU/mL and a vital embryo was present.

Materials and Methods

A literature search was carried out on MEDLINE, EMBASE, and PUBMED. We identified two cases of IP referred to the Institute for Maternal and Child Burlo Garofolo, Trieste. Data related to clinical presentation, β-hCG, and ultrasound scan at the moment of the diagnosis were recorded. In one of the cases, the β-hCG level was >10.000 mIU/mL, and a vital embryo was testified at an ultrasound scan. The patient was asymptomatic and she was treated using multidose systemic Methotrexate (MTX) combined with Mifepristone. In the second case, in the presence of a clinically stable patient with β − hCG > 10.000 mIU/mL, it was chosen that the administration of Mifepristone combined with a double dose of MTX. β-hCG levels and ultrasound examinations were performed weekly until a complete resolution of the IP.

Results

In the first case, β-hCG dropped down in 5 days and became undetachable in 30 days. In the second case, β-hCG became undetectable in 47 days. The first-line therapy in asymptomatic women could be addressed to a combined protocol, consisting of a systemic multidose MTX regimen with a single oral dose of Mifepristone.

Conclusions

Clinical management of IP remains a debated topic. In selected cases, a systemic multidose MTX regimen combined with a single oral dose of Mifepristone could be considered also in the presence of high serum β-hCG.

Interventions for tubal ectopic pregnancy

BACKGROUND

Treatment options for tubal ectopic pregnancy are; (1) surgery, e.g. salpingectomy or salpingo(s)tomy, either performed laparoscopically or by open surgery; (2) medical treatment, with a variety of drugs, that can be administered systemically and/or locally by various routes and (3) expectant management.

OBJECTIVES

To evaluate the effectiveness and safety of surgery, medical treatment and expectant management of tubal ectopic pregnancy in view of primary treatment success, tubal preservation and future fertility.

SEARCH STRATEGY

The Cochrane Menstrual Disorders and Subfertility Group's Specialised Register, Cochrane Controlled Trials Register (up to February 2006), Current Controlled Trials Register (up to October 2006), and MEDLINE (up to October 2006) were searched.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing treatments in women with tubal ectopic pregnancy.

DATA COLLECTION AND ANALYSIS

Data extraction and quality assessment was done independently by two reviewers. Differences were resolved by discussion with all reviewers.

MAIN RESULTS

Thirty five studies have been analysed on the treatment of tubal ectopic pregnancy, describing 25 different comparisons.

SURGERY

Laparoscopic salpingostomy is significantly less successful than the open surgical approach in the elimination of tubal ectopic pregnancy (2 RCTs, n=165, OR 0.28, 95% CI 0.09, 0.86) due to a significant higher persistent trophoblast rate in laparoscopic surgery (OR 3.5, 95% CI 1.1, 11). However, the laparoscopic approach is significantly less costly than open surgery (p=0.03). Long term follow-up (n=127) shows no evidence of a difference in intra uterine pregnancy rate (OR 1.2, 95% CI 0.59, 2.5) but there is a non significant tendency to a lower repeat ectopic pregnancy rate (OR 0.47, 95% 0.15, 1.5). Salpingostomy alone is significantly less successful than when combined with a prophylactic single shot methotrexate (2 RCTs, n=163, OR 0.25, 95% CI 0.08-0.76) to prevent persistent trophoblast.

MEDICAL TREATMENT

Systemic methotrexate in a fixed multiple dose intramuscular regimen has a non significant tendency to a higher treatment success than laparoscopic salpingostomy (1 RCT, n=100, OR 1.8, 95% CI 0.73, 4.6). No significant differences are found in long term follow-up (n=74): intra uterine pregnancy (OR 0.82, 95% CI 0.32, 2.1) and repeat ectopic pregnancy (OR 0.87, 95% CI 0.19, 4.1). One single dose intramuscular methotrexate is significantly less successful than laparoscopic salpingostomy (4 RCTs, n=265, OR 0.38, 95% CI 0.20, 0.71). With a variable dose regimen treatment success rises, but shows no evidence of a difference compared to laparoscopic salpingostomy (OR 1.1, 95% CI 0.52, 2.3). Long term follow-up (n=98) do not differ significantly (intra uterine pregnancy OR 1.0, 95% CI 0.43, 2.4, ectopic pregnancy OR 0.54, 95% CI 0.12, 2.4). The efficacy of systemic single dose methotrexate alone is significantly less successful than when combined with mifepristone (2 RCTs, n=262, OR 0.59, 95% CI 0.35, 1.0). The same goes for the addition of traditional Chinese medicine (1 RCT, n=78, OR 0.08, 95% CI 0.02, 0.39). Local medical treatment administered transvaginally under ultrasound guidance is significantly better than a 'blind' intra-tubal injection under laparoscopic guidance in the elimination of tubal ectopic pregnancy (1 RCT, n=36, methotrexate OR 5.8, 95% CI 1.3, 26; 1 RCT, n=80, hyperosmolar glucose OR 0.38, 95% CI 0.15, 0.93). However, compared to laparoscopic salpingostomy, local injection of methotrexate administered transvaginally under ultrasound guidance is significantly less successful (1 RCT, n=78, OR 0.17, 95% CI 0.04, 0.76) but with positive long term follow up (n=51): a significantly higher intra uterine pregnancy rate (OR 4.1, 95% CI 1.3, 14) and a non significant tendency to a lower repeat ectopic pregnancy rate (OR 0.30, 95% CI 0.05, 1.7). EXPECTANT MANAGEMENT: Expectant management is significantly less successful than prostaglandin therapy (1 RCT, n=23, OR 0.08, 95% CI 0.02-0.39).

AUTHORS' CONCLUSIONS

In the surgical treatment of tubal ectopic pregnancy laparoscopic surgery is a cost effective treatment. An alternative nonsurgical treatment option in selected patients is medical treatment with systemic methotrexate. Expectant management can not be adequately evaluated yet.