(800) Variation in genetic workup of polyhydramnios: An international and inter-specialty survey

To evaluate the opinions of health professionals regarding the definition of polyhydramnios in which invasive testing is considered, as well as the optimal genetic testing in such cases.

Study Design:

This anonymous electronic survey was conducted using the Fetal Sequencing Consortium and COGEN mailing list. The survey included questions about the country of origin, the main specialty of the respondent (i.e., clinical geneticist, MFM geneticist, MFM non-genetics professional, genetic counselor, and others), sonographic criteria for recommendation of invasive testing in cases of polyhydramnios (i.e., mild polyhydramnios, moderate/severe polyhydramnios or only in the presence of additional sonographic aberrations such as fetal akinesia or malformations), as well as the recommended genetic testing in such cases.

Results:

Of the 154 healthcare practitioners participatung in the survey, 17.8% would recommend invasive testing in any case of mild polyhydramnios (defined as amniotic fluid index (AFI) of ≥24 cm or maximal vertical pocket (MVP) of ≥8 cm), 19.9% - only in moderate and severe polyhydramnios (AFI of ≥30cm or MVP ≥12 cm), while 41.8% - only in the presence of additional sonographic anomalies. 30.5% recommend fetal karyotyping for genetic testing, 25.3% - FISH/QF-PCR, 85.1% - chromosomal microarray analysis, 50.0% - exome sequencing, 13.0% - genome, and 36.3% - genetic testing for specific genetic disorders (Myotonic Dystrophy, Spinal Muscular Atrophy and Prader-Willi syndrome). The answers differed by country of origin, as well as the medical specialty of the respondents (Figure 1, statistically significant differences noted by star).   

Conclusion:

Pronounced differences in the genetic management of polyhydramnios were noted, partly depending on geographic and professional factors. Large-scale studies should be performed to facilitate the establishment of uniform guidelines on this matter.