Management and outcome of fetal abdominal cyst in first trimester: systematic review of the literature

Abstract

Objective: The detection of a fetal abdominal cyst at the first-trimester ultrasound scan is a rare event, for which the natural history and prognosis are often unknown and unpredictable, owing to various underlying etiologies. The aim of this study was to evaluate the outcome of fetal abdominal cysts detected in the first trimester to better understand their possible clinical significance and improve their clinical management.

Methods: We present a case report of a fetal abdominal cyst detected in the first trimester, with subsequent diagnosis of congenital multiple arthrogryposis. We also performed a systematic review of the literature to determine the incidence and outcome of similar cases, which was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and registered with PROSPERO (CRD42023491729). PubMed, Web of Science and EMBASE were searched from inception to December 2023 to identify case reports and case series documenting an ultrasound diagnosis of a single fetal abdominal cyst in the first trimester.

Results: Our case presented at 12 + 6 weeks' gestation with an isolated fetal abdominal cyst, which underwent spontaneous resolution in the second trimester, when multiple congenital arthrogryposis was observed. Data on a total of 60 cases of fetal abdominal cyst detected in the first trimester were extracted from the literature. Of these, 35% were associated with concurrent or late-onset structural anomalies, as in our case, and 65% were isolated. In pregnancies with an isolated fetal abdominal cyst, 54% had a live birth with a normal outcome.

Conclusions: A fetal abdominal cyst in the first trimester is usually an isolated finding with a moderate-to-good prognosis, but it could also be an early sign of other associated abnormalities, including arthrogryposis. Increased ultrasound surveillance and additional genetic testing to rule out possible associated anomalies are necessary to assess the risk of adverse pregnancy outcome and provide appropriate parental counseling. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Keywords: fetal abdominal cyst; fetal malformation; first‐trimester anomaly; first‐trimester screening; prenatal diagnosis; ultrasound.

Figure 1

Transabdominal ultrasound images at 12 + 6 weeks' gestation, showing fetal upper‐abdomen cyst (calipers) behind stomach in transverse (a) and longitudinal (b) views, and normal bladder in longitudinal view (c).

Figure 2

Transabdominal ultrasound images at follow‐up scan at 17 + 6 weeks' gestation. (a) Transverse view of normal fetal abdomen, with no sign of cyst. (b) Longitudinal view showing fetal arthrogryposis, with leg and wrist hyperextended and fixed, and with clenched hand. (c) Clubfoot.

Figure 3

PRISMA flowchart summarizing inclusion of studies in systematic review.

Figure 4

Flowchart summarizing findings and outcome in 60 fetuses diagnosed with abdominal cyst in first trimester (11–14 weeks' gestation) reported in literature. IUD, intrauterine death; LB, live birth; TOP, termination of pregnancy.

Figure 5

Proposed algorithm for prognostic evaluation of fetuses with diagnosis of abdominal cyst in first trimester (11–14 weeks' gestation). CGH, comparative genomic hybridization; CVS, chorionic villus sampling; GI, gastrointestinal; US, ultrasound.

Figure 6

Proposed algorithm for prognostic evaluation of fetuses with diagnosis of abdominal cyst in first trimester (11–14 weeks' gestation). GI, gastrointestinal.