Conservative management of interstitial pregnancies: experience of a single centre.

The aim of this study was to compare the effect of local intracavitary methotrexate (MTX) injection and laparoscopic (L/S) cornuostomy in the treatment of interstitial pregnancy (IP) in terms of clinical and reproductive outcome. The data of patients with IP (n:10) who were treated between September 2011 and December 2016 with either an intra-amniotic MTX injection (n:7) or L/S cornuostomy (n:3) were retrospectively evaluated. All cases (7/7) in the local injection group and two (2/3) in the L/S group were successfully treated with the initial treatment. One case (1/3, 33%) in L/S group needed systemic MTX due to an elevated β-hCG. No serious complication or secondary surgical intervention was observed in the study group. Five (71.4%) women in MTX group and two (66%) women in the L/S group had pregnancy after index case (p > .05). Post-treatment (hysterosalpingography) HSG results revealed that tubal patency was significantly higher in the MTX group (7/7 (100%) vs. 0/3 (0%) p < .05). Conservative treatment of IP with both methods was generally successful with regard to maternal morbidity and reproductive function. However, local MTX was superior for tubal patency compared to L/S cornuostomy. Since this is a retrospective study including a small study population, our results should be confirmed with larger prospective studies. Impact Statement What is already known on this subject? Earlier diagnosis of an interstitial pregnancy (IP) enables clinicians to pursue more conservative treatment modalities that can prevent morbidity (severe bleeding, rupture and massive transfusion, etc.) and loss of fertility. MTX treatment and conservative laparoscopic surgical procedures are gaining importance. High serum β-hCG levels and positive foetal cardiac activity are known as unfavourable pre-treatment prognostic predictors for systemic MTX treatment in patients with an ectopic pregnancy. Local MTX treatment is widely used for caeserean scar pregnancies or cervical pregnancies. L/S cornuostomy is an attractive alternative to L/S cornual resection, because it preserves the normal uterine myometrium. What the results of this study add? In the present study, we showed that the local MTX and laparoscopic cornuostomy were successful methods in IP patients and did not impair the fertility potential of the patients. We also demonstrated that local MTX application is superior to L/S cornuostomy in terms of the post-treatment tubal patency and this fact should be kept in mind when tailoring the treatment in patients desiring pregnancy. What the implications are of these findings for clinical practice and/or further research? The value of local MTX injection in cases with IP and high β-hCG levels should be further clarified.