Prenatal Guidelines

PreventionGenetics should be notified in advance of arrival of a prenatal specimen. For all prenatal testing in ongoing pregnancies, we require a signature from the health care provider on our PRENATAL HEALTH CARE PROVIDER'S STATEMENT FORM. We expect that the ordering provider will take responsibility for the appropriateness of the requested testing.

We accept fetal DNA, fetal tissue, cultured fetal cells, or direct CVS/amniotic fluid. However, acceptable specimen type is dependent on the fetal testing requested (see Specimen Requirements for more information). Retention of a back-up cell culture is required for NextGen Sequencing (NGS) requests and strongly recommended for other prenatal testing requests. PreventionGenetics offers cell culturing (see below for details). Cell culturing should be ordered separately if needed. Where possible, please ship prenatal specimens so that they will arrive at PreventionGenetics no later than Thursday in the work week. When ordering shipping labels for prenatal specimens or kits for prenatal parental specimens, please note "prenatal" in the comments field on the kit order page.

We currently offer chromosomal microarray (CMA), known familial variant, full gene, panel, and Prenatal PGxome testing for ongoing pregnancies. Prenatal testing via full gene, panel, or whole exome sequencing (WES) will only be performed when there is a fetal indication, such as ultrasound anomalies or other abnormal test results. Full gene or panel testing can be done based on an abnormal CMA result which predisposes the fetus to a recessive condition. However, Absence or Loss of Heterozygosity (AOH/LOH) alone does not qualify for prenatal testing. CMA testing can be performed when there is an indication of a fetal anomaly and/or for advanced maternal age (≥ 35 years). Prenatal testing for family history will be performed only when there is a known familial variant(s) with familial positive control(s) available. In a situation where one parent is a known carrier for a recessive disorder, we require the other parent to be tested prior to fetal testing; prenatal testing for the known familial variants can then be pursued. Prenatal testing will not be performed solely because of parental anxiety.

All prenatal testing for ongoing pregnancies is expedited. See below for turnaround times.

We require at least one parental specimen be sent as part of prenatal testing for QA purposes.

Maternal cell contamination (MCC) of fetal specimen will be tested using the PreventionGenetics DNA Genotyping Panel. Even in cases of autosomal dominant disorders in which the father has the causative variant, blood or DNA from the mother is strongly encouraged to be sent for the MCC test. We do not charge extra for MCC studies for any fetal testing, but the CPT Code 81265 will be included on invoices and insurance claims as appropriate.

At this time, PreventionGenetics is not validated to offer prenatal testing for most MLPA or repeat expansion testing.

PreventionGenetics does not perform prenatal testing for sex. We will also not report fetal sex unless this is critical for interpretation of test results. PreventionGenetics does not perform pre-implantation DNA testing.

In the case of fetal demise or pregnancy termination, no "PRENATAL HEALTH CARE PROVIDER'S STATEMENT" is required, and our standard prices, specimen requirements, and turnaround times apply.

Familial Variant Testing (Test Code 990)

See our Targeted Testing page for additional test details and ordering.

Familial Sequence Variant

Familial variants must be known in advance from testing of parents, affected siblings, or other relatives. These variants must be confirmed at PreventionGenetics in the parents and/or proband. Parental specimens may be sent in advance of the prenatal specimen. Additional CPT codes for parental and MCC testing may be included at time of invoicing. We require at least one parental specimen be sent for all targeted prenatal testing requests.

Familial Copy Number Variation (CNV)

If a familial copy number variation (CNV) was identified via gene-centric aCGH and was confirmed by PCR in the proband, the PCR-based test is an option for a subsequent pregnancy only when the father is a carrier of the CNV. When the mother is a carrier, prenatal testing must be performed by aCGH due to the possibility that even a low level of maternal cell contamination may affect the interpretation of a PCR-based test. Please contact our Genetic Counseling Team to discuss any familial CNV situations.

Positive control(s) is required.

Turnaround Time: Default STAT TAT - 2 weeks on average.

CNV Analysis via Chromosomal Microarray (CMA) (see Del/Dup Array Tests)

We will perform CMA - Rapid Prenatal for ongoing pregnancies. See our full Test Descriptions for additional test details and limitations.

Turnaround Time: CMA - Rapid Prenatal has a turnaround time of 1 weeks on average. Rarely, the need for confirmation and/or technical difficulties may increase this time.

Prenatal PGxome (see Prenatal PGxome test description)

We will perform WES for ongoing pregnancies when there is an indication (usually ultrasound or other) of a fetal anomaly. See our full Test Description for additional test details and limitations.

Retention of a back-up cell culture is required for NextGen Sequencing (NGS) requests. Cell culturing should be ordered separately if needed.

Turnaround Time: 2 weeks on average.

NextGen Sequencing (see prenatal prices listed on our website)

We will perform NextGen sequencing (NGS) tests for ongoing pregnancies when there is an indication (usually ultrasound or other) of a fetal anomaly. See our test-specific descriptions for additional test details and limitations. NGS tests for ongoing pregnancies require cultured cells.

Retention of a back-up cell culture is required for NextGen Sequencing (NGS) requests. Cell culturing should be ordered separately if needed.

Turnaround Time: 2 weeks on average.

Full Gene Sanger Sequencing (see prenatal prices listed on our website)

We will perform full gene Sanger sequencing tests for ongoing pregnancies when there is an indication (usually ultrasound or other) of a fetal anomaly. See our test-specific descriptions for additional test details and limitations.

Turnaround Time: 2 weeks on average.

CNV Analysis via Gene-Centric aCGH Test (see prenatal prices listed on our website)

We will perform gene-centric aCGH for prenatal specimens when there is an indication (usually ultrasound or other) of a fetal anomaly. At this time MLPA is not validated for prenatal specimen types. Please contact our Genetic Counseling Team to discuss any familial CNV situations. See our full Test Description for additional test details and limitations.

Turnaround Time: 2 weeks on average.

Fetal Cell Culturing

Fetal cell cultures are available from direct amniotic fluid, chorionic villi, or products of conception (POC). Retention of a back-up cell culture is required for NextGen Sequencing (NGS) requests. See our Cell Cultures page for more details.