Non‐immune fetal hydrops: etiology and outcome according to gestational age at diagnosis

Abstract

Objective Fetal hydrops is associated with increased perinatal morbidity and mortality. The etiology and outcome of fetal hydrops may differ according to the gestational age at diagnosis. The aim of this study was to evaluate the cause, evolution and outcome of non‐immune fetal hydrops (NIFH), according to the gestational age at diagnosis. Methods This was a retrospective cohort study of all singleton pregnancies complicated by NIFH, at the Fetal Medicine Unit at St George's University Hospital, London, UK, between 2000 and 2018. All fetuses had detailed anomaly and cardiac ultrasound scans, karyotyping and infection screening. Prenatal diagnostic and therapeutic intervention, gestational age at diagnosis and delivery, as well as pregnancy outcome, were recorded. Regression analysis was used to test for potential association between possible risk factors and perinatal mortality. Results We included 273 fetuses with NIFH. The etiology of the condition varied significantly in the three trimesters. Excluding 30 women who declined invasive testing, the cause of NIFH was defined as unknown in 62 of the remaining 243 cases (25.5%). Chromosomal aneuploidy was the most common cause of NIFH in the first trimester. It continued to be a significant etiologic factor in the second trimester, along with congenital infection. In the third trimester, the most common etiology was cardiovascular abnormality. Among the 152 (55.7%) women continuing the pregnancy, 48 (31.6%) underwent fetal intervention, including the insertion of pleuroamniotic shunts, fetal blood transfusion and thoracentesis. Fetal intervention was associated significantly with lower perinatal mortality (odds ratio (OR), 0.30 (95% CI, 0.14–0.61); P < 0.001); this association remained significant after excluding cases with a diagnosis of anemia or infection (OR, 0.29 (95% CI, 0.13–0.66); P = 0.003). In 104 fetuses not undergoing active fetal intervention, the gestational age at diagnosis was the only parameter that was significantly associated with the risk of perinatal mortality (OR, 0.92 (95% CI, 0.85–0.99); P = 0.035), while the affected body cavity and polyhydramnios were not (P > 0.05). Conclusions An earlier gestational age at diagnosis of NIFH was associated with an increased risk of aneuploidy and worse pregnancy outcome, including a higher risk of perinatal loss. Fetal therapy was associated significantly with lower perinatal mortality. © 2020 Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Clinical Course and Outcome of Non-Immune Fetal Hydrops in Singleton Pregnancies

“…The rate of ToP in our cohort with 50.8% (183 cases) is consistent with previously published literature (44.3%) [12]. The decision on ToP was associated with etiology, elevated NT thickness, and GA at diagnosis.…”

“…While literature concerning ToP in fetal hydrops is sparse, many investigations have already confirmed high rates of ToP in the case of prenatally detected chromosomal aberration, especially if trisomy 21 was diagnosed [13][14][15]. The association of early diagnosis and ToP is consistent with the results from Sileo et al [12] and relatable due to the expected worse outcome and emotional factors later in pregnancy such as the sense of fetal movement.…”

Fetal hydrops and the Incremental yield of Next‐generation sequencing over standard prenatal Diagnostic testing (FIND) study: prospective cohort study and meta‐analysis

“…This supports the use of ES or whole-genome sequencing (WGS), rather than a targeted or stepwise approach, in the investigation of NIHF 37 . The role of QF-PCR or conventional karyotyping in NIHF should always be respected, given the high incidence of aneuploidy 38 . However, given the limited additional yield of CMA over karyotyping, and considering the ability of WGS to detect both structural variants and aneuploidy, it may be reasonable in the future to consider WGS as the second-line test after QF-PCR 5 .…”

Nonimmune Hydrops Fetalis—Prenatal Diagnosis, Genetic Investigation, Outcomes and Literature Review

“…In this study, the median gestational age at the time of diagnosis was 24 weeks (range: 15–36 weeks). In the recent study by Sileo et al, who analysed a group of 279 foetuses with hydrops, the aetiology of NIFH was suggested to vary significantly depending on the gestational age at the time of diagnosis [ 25 ]. This was also observed in our group, as the most common causes of NIHF in the earliest gestational group were aneuploidy and heart defects.…”