Clinical factors associated with uterine rupture in type II angular pregnancy: a 10-year single-institution retrospective study.

Objective: To introduce the classification and focus on retrospectively investigating clinical factors associated with uterine rupture. Materials and methods: We retrospectively analyzed 222 cases of angular pregnancies from January 2010 and December 2021. The selected cases were classified into two types, type I (n = 19) and type II (n = 199). Additionally, type II cases were further subdivided into the ruptured group (n = 25) and the unruptured group (n = 174). Clinical data were collected, and univariate and multivariate analyses were performed to identify significant indicators. Results: The mean maternal age was 31.5 ± 5.8 years, with a mean BMI (body mass index) of 22.0 ± 3.2 kg/m2 in 199 type II patients. Spontaneous uterine rupture occurred in 25 (12.6%) patients, while 174 (87.4%) remained unruptured. Univariate analysis revealed that abdominal pain (P < 0.001), a history of previous ipsilateral salpingectomy (P = 0.002), vaginal bleeding (P = 0.005), and gestational age (GA) ≥ 7 weeks (P = 0.044) were significant factors of rupture in type II angular pregnancy. Multivariate analysis identified abdominal pain (OR = 10.410, 95% CI: 3.286-32.977, P < 0.000) and ipsilateral salpingectomy (OR = 3.270, 95% CI: 1.209-8.847, P = 0.020) as statistically significant independent risk factors. The ruptured group had clinically and statistically significant lower hemoglobin and higher transfusion rates. Conclusion: The classification system of angular pregnancy (AP) is a valuable tool that facilitates appropriate management and good prognostic outcomes. Type I angular pregnancy can be followed up till term. Type II angular pregnancy is a high-risk form, and clinicians must carefully assess and investigate other factors such as the history of ipsilateral salpingectomy and abdominal pain and high alert for uterine rupture.