Surgical treatment of fallopian tubal pregnancy and interstitial pregnancy has no differential effect on intrauterine pregnancy after in vitro fertilization-embryo transfer.

Background: Due to the specific nature of interstitial pregnancy (IP), there are significant risks to both the mother and the foetus in women with a heterotopic interstitial pregnancy (HIP). IP alone has been analysed as a site-specific ectopic pregnancy (EP) in previous studies; however, according to the latest European Society of Human Reproduction and Embryology criteria, IP is classified as a tubal pregnancy. If IP can be classified as a tubal pregnancy, then there is no difference in the effects of these two methods on intrauterine pregnancies (IUPs). Under the premise of timely surgery, disposing of IPs and tubal pregnancy (excluding IPs) should also have no differential effect on IUPs.

Methods: Patients with heterotopic fallopian tubal pregnancy (HP-tube) and HIP seen at our hospital from January 2005 to December 2020 were included. All included patients were diagnosed by transvaginal sonography (TVS), and EPs were confirmed by surgery and pathological analysis. The IUP outcomes after surgical treatment of the EPs were compared between the HP-tube group (n = 464) and the HIP group (n = 206). The outcomes of IUPs were evaluated in patients with HIP who underwent either laparoscopy (169 cases) or laparotomy (36 cases).

Results: There was no significant difference in postoperative miscarriage (6.90% vs. 6.80%, odds ratio (OR) = 1.859, 95% confidence interval (CI) (0.807-4.279), p = 0.145); early spontaneous miscarriage (19.61% vs. 18.93%, OR = 0.788, 95% CI (0.495-1.255), p = 0.316); or late miscarriage (0.43% vs. 0.49%, OR = 0.823, 95% CI (0.070-9.661), p = 0.877) between the HP-tube group and the HIP group. There was no significant difference between the two groups in terms of preterm birth (7.33% vs. 6.80%, OR = 1.044, 95% CI (0.509-2.139), p = 0.907), live birth rate (71.60% vs. 73.30%, OR = 1.010, 95% CI (0.670-1.530), p = 0.980), or perinatal mortality rate (2.00% vs. 0.65%, OR = 0.580, 95% CI (0.030-3.590), p = 0.620). Compared to laparotomy for HIPs, laparoscopic treatment was associated with similar rates of postoperative miscarriage (5.33% vs. 13.90%, p = 0.076), live birth rate (72.80% vs. 75.00%, p = 0.948), caesarean Sect. (83.90% vs. 77.80%, p = 0.414).

Conclusions: After early diagnosis and treatment of EPs, patients in the HP-tube and HIP groups achieved comparable outcomes. Laparotomy and laparoscopy for treating HIPs yielded similar pregnancy outcomes.