A 31-Year-Old Primigravida Woman Presenting at 18 Weeks of Gestation With Right Ovarian Torsion Successfully Managed With Laparoscopic Adnexectomy

Introduction

Ovarian torsion refers to the rotation of an ovary around the axis formed by the infundibulopelvic ligament and the utero-ovarian ligament. This rotation results in disruption of adnexal circulation, initially compromising venous return and subsequent arterial inflow, ultimately leading to tissue ischemia. Without timely intervention, ovarian tissue becomes necrotic, and cytokines released from necrotic tissue can trigger peritonitis [1].

During pregnancy, ovarian torsion occurs in approximately 1 to 10 per 10 000 spontaneous pregnancies [2,3], in 6% of cases following ovarian stimulation, and in up to 16% following ovarian hyperstimulation [4]. It is usually observed within the first 11 weeks of gestation [5], coinciding with the high prevalence of functional cysts (eg, corpus luteum cysts and benign teratomas) during early pregnancy. The right adnexa are more frequently involved [1], a finding attributed to 2 anatomical factors: the relatively greater length of the right utero-ovarian ligament, which facilitates torsion, and the presence of the sigmoid colon on the left, which limits available space for torsion to occur [6].

Diagnosis is primarily clinical, based on the presentation of acute pelvic pain – often sharp and radiating to the flank or groin – in approximately 90% of cases, more commonly on the right side. Nausea and vomiting frequently accompany the pain, and low-grade fever is present in roughly 20% of patients. Laboratory tests are not diagnostic but can reveal leukocytosis secondary to the necrosis-related inflammatory response [3,6].

Transvaginal ultrasonography is useful for identifying adnexal masses or cysts and can reveal free fluid in the pouch of Douglas [7]. Doppler flow typically demonstrates absent vascular flow; however, arterial flow occasionally persists. Certain sonographic features, such as the whirlpool sign, are characteristic of adnexal torsion, but are not always present [8]. Computed tomography (CT) can aid diagnosis but is contraindicated during pregnancy [9]. Magnetic resonance imaging (MRI) can be used as a diagnostic adjunct, although its routine use is limited by higher costs and longer acquisition times.

Definitive diagnosis is surgical, with laparoscopy being the preferred approach [10], although the open approach is still used [1,3]. The primary goal is adnexal preservation, achieved through detorsion when there is no evidence of necrosis and when reperfusion is observed. If necrosis is present, unilateral adnexectomy is indicated. Whenever possible, a conservative surgical strategy is recommended, although the risk of subsequent cyst formation remains [11].

Case Report

A 31-year-old German primigravida woman at 18 weeks of physiological gestation presented to our Emergency Department with acute abdominopelvic pain localized to the right iliac fossa. Initial laboratory investigations revealed normal inflammatory parameters (white blood cell [WBC] count 11 000/μL, C-reactive protein [CRP]-negative). Gynecological examination showed a non-contracted uterus, closed cervix, and cervical length of 3 cm. Obstetric ultrasound confirmed normal fetal health.

A surgical consultation was obtained, and an abdominal ultrasound was performed, yielding negative findings. In the absence of peritoneal signs, the clinical decision was to monitor inflammatory indices and re-evaluate subsequently. No vaginal bleeding was reported.

Several hours later, the patient experienced worsening pain. Laboratory re-assessment revealed leukocytosis (WBC 12 900/μL) with persistently negative CRP. Despite antibiotic and analgesic therapy, her symptoms further deteriorated. Repeat transabdominal ultrasound demonstrated periuterine free fluid and a right iliac fossa mass of probable adnexal origin measuring approximately 7×5 cm, with markedly reduced vascularization on Doppler imaging (Figure 1).

Given the onset of early peritoneal signs, diagnostic and operative laparoscopy was indicated for suspected right adnexal torsion, following informed consent. Entry into the peritoneal cavity was performed via open laparoscopy with a 10-mm umbilical port, positioned slightly cephalad to accommodate the gravid uterus. Two lateral 5-mm accessory trocars were placed. Due to the enlarged uterine volume obstructing visualization of the ultrasonographically identified mass, a third trocar was positioned on the right side, 5 cm caudal to the ipsilateral port, rather than at the standard midline suprapubic site.

The left-sided trocar was used exclusively for gentle uterine retraction to permit visualization of the pouch of Douglas, while the 2 right-sided ports served as operative channels for bipolar forceps and scissors. Laparoscopic inspection revealed an enlarged right adnexa prolapsed into the pouch of Douglas, associated with hemoperitoneum. The gravid uterus extended to the infraumbilical region, and the left adnexa appeared normal. Torsion of the right adnexa was confirmed intraoperatively (Figure 2).

Detorsion was attempted; however, after several minutes of observation, no reperfusion was evident. The adnexa remained gray-bluish with necrotic-hemorrhagic areas consistent with irreversible ischemic damage (Figure 3). Given the absence of vascular recovery, a right adnexectomy was performed, followed by aspiration of hemoperitoneum from the pouch of Douglas.

The postoperative course was uneventful, and follow-up obstetric evaluations were normal. Histopathological examination confirmed extensive necrosis and irreversible tissue damage. The patient was discharged 2 days postoperatively in good maternal and fetal condition and subsequently returned to Germany.

Discussion

Ovarian torsion during an otherwise physiological pregnancy is an uncommon event, and its occurrence at 18 weeks of gestation is particularly rare, as supported by the literature [1,3]. Early identification of the condition, even in atypical periods of onset, and early laparoscopic intervention may be a valid approach.

Typically, this complication develops within the first 11 weeks of gestation, coinciding with a higher incidence of functional ovarian cysts during this period [6]. No risk factors were identified in the patient’s medical history, and the diagnosis was primarily clinical, as neither laboratory tests nor imaging provided definitive evidence.

Laparoscopy was employed as the surgical technique [2]. Intraoperatively, torsion of the ovary was confirmed, resulting in ischemia and necrosis of the adnexa. This complication is rare in pregnancy, especially at 18 weeks, as corroborated by scientific reports. The gravid uterus and the state of pregnancy complicate the differential diagnosis of acute abdominal pain [4].

There is still debate in the literature about which approach to use in treating this condition: laparoscopic or open surgery. Some authors prefer to use laparotomy, an approach that is more invasive and has more complications but allows for management of more complicated cases [1,3].

Conclusions

The onset of ovarian torsion in mid-pregnancy is a rare complication that is difficult to identify until it reaches a complicated stage, as the symptoms can mimic other gastrointestinal or pelvic disorders. Transvaginal and abdominal ultrasound (especially when performed by experienced personnel) can help identify this condition, but surgery, especially laparoscopy, is the most optimal treatment and identification method for managing these cases.