Evidence-Based Supplement & Herb Guides

Down Syndrome Genetic Test: Trisomy 21 Screening, Diagnosis, and Results

Understand Down syndrome genetic testing, including trisomy 21 screening, CVS and amniocentesis diagnosis, chromosome results, recurrence, and next steps.

A Down syndrome genetic test can estimate the chance that a pregnancy is affected by trisomy 21 or confirm whether an extra copy of...

Edwards Syndrome Genetic Test: Trisomy 18 Screening, Diagnosis, and Results

Learn how Edwards syndrome genetic testing screens for and diagnoses trisomy 18, how results are reported, and what they mean for care and recurrence.

An Edwards syndrome genetic test looks for extra chromosome 18 material, a finding called trisomy 18. During pregnancy, some tests estimate the chance of...

Embryo Genetic Testing: IVF, Chromosomes, Mutations, and Results

Understand embryo genetic testing in IVF, including PGT-A, PGT-M, PGT-SR, biopsy, mosaic results, limitations, embryo transfer, and prenatal confirmation.

Embryo genetic testing examines a small group of cells from embryos created through in vitro fertilization. The test can look for extra or missing...

Fetal Aneuploidy Test: Trisomy, Monosomy, Chromosome Risk, and Results

Understand fetal aneuploidy testing for trisomy, monosomy, chromosome risk, screening results, diagnostic confirmation, mosaicism, and next steps.

A fetal aneuploidy test evaluates whether a pregnancy may have an extra or missing chromosome. An extra copy is called a trisomy; a missing...

First-Trimester Screening Test: Down Syndrome Risk, PAPP-A, hCG, and Results

Understand first-trimester screening for Down syndrome risk, including PAPP-A, hCG, nuchal translucency, result ratios, limitations, and follow-up options.

First-trimester screening combines an ultrasound measurement with pregnancy-related blood markers to estimate the chance of Down syndrome and, in many programs, trisomy 18 and...

Karyotype Test for Infertility: Chromosome Abnormalities and Results

Understand infertility karyotype testing, including chromosome abnormalities, male and female findings, result notation, limitations, and reproductive options.

A karyotype test for infertility examines the number and large-scale structure of chromosomes in a blood sample. It can identify findings such as Klinefelter...

Klinefelter Syndrome Genetic Test: XXY Chromosomes, Diagnosis, and Results

Understand Klinefelter syndrome genetic testing, including 47,XXY and mosaic results, prenatal confirmation, hormone follow-up, fertility options, and next steps.

Klinefelter syndrome is a chromosome condition most often caused by an extra X chromosome in a person who also has a Y chromosome. The...

Maternal Serum AFP Test: Neural Tube Defect Risk and Pregnancy Results

Learn how the maternal serum AFP test screens for open neural tube defects, how MoM results are calculated, why AFP may be high, and what follow-up involves.

The maternal serum alpha-fetoprotein test, usually shortened to MSAFP, is a second-trimester blood screening test used mainly to estimate the chance of an open...

Newborn Cystic Fibrosis Screening Test: IRT, CFTR, and Results

Understand newborn cystic fibrosis screening, including IRT, CFTR variant results, sweat chloride confirmation, carrier findings, and CRMS/CFSPID follow-up.

Newborn cystic fibrosis screening starts with a few drops of blood collected on a filter-paper card. The laboratory first measures immunoreactive trypsinogen, or IRT,...

Newborn SCID Screening Test: TREC, Immune Deficiency, and Results

Understand newborn SCID screening, including TREC results, causes of low T cells, confirmatory flow cytometry, urgent precautions, genetic testing, and treatment.

Newborn screening for severe combined immunodeficiency, or SCID, measures tiny DNA circles called TRECs in a dried blood spot. TRECs are produced when new...

Newborn Screening Genetic Test: Inherited Metabolic Disorders and Results

Understand newborn screening for inherited metabolic disorders, including blood-spot markers, abnormal results, time-critical follow-up, confirmatory tests, and genetics.

Newborn blood-spot screening looks for signs of serious conditions before a baby becomes visibly ill. Many of the target conditions are inherited metabolic disorders,...

Newborn SMA Screening Test: SMN1 Gene, Early Diagnosis, and Results

Understand newborn SMA screening, SMN1 and SMN2 results, confirmatory testing, early treatment decisions, missed variants, and family planning after an abnormal result.

Newborn screening for spinal muscular atrophy (SMA) can identify many affected babies before weakness is visible. The test uses the routine heel-prick blood spot...

Noninvasive Prenatal Testing (NIPT): Trisomy 21, Trisomy 18, Trisomy 13, and Results

Learn how NIPT screens for trisomy 21, trisomy 18, and trisomy 13, what low-risk, high-risk, and no-call results mean, and when diagnostic testing is needed.

Noninvasive prenatal testing (NIPT), also called prenatal cell-free DNA screening, estimates the chance that a pregnancy has trisomy 21, trisomy 18, or trisomy 13...

Parental Karyotype Test: Infertility, Miscarriage, Translocations, and Results

Learn how a parental karyotype test can identify balanced translocations and other chromosome changes linked to infertility, recurrent miscarriage, and pregnancy risk.

A parental karyotype test examines the number and visible structure of chromosomes in one or both partners. It may help explain recurrent miscarriage, severe...

Patau Syndrome Genetic Test: Trisomy 13 Screening, Diagnosis, and Results

Understand Patau syndrome genetic testing, including trisomy 13 screening, CVS and amniocentesis diagnosis, result interpretation, prognosis, and recurrence risk.

Patau syndrome genetic testing looks for an extra copy of chromosome 13, a finding called trisomy 13. Prenatal screening can estimate the chance that...

Preimplantation Genetic Testing (PGT): IVF Embryo Testing and Results

Learn how PGT works in IVF, including PGT-A, PGT-M, and PGT-SR, embryo biopsy, result terms, limitations, transfer decisions, costs, and prenatal follow-up.

Preimplantation genetic testing, or PGT, analyzes a small sample of cells from embryos created through in vitro fertilization before an embryo is selected for...

Preimplantation Genetic Testing for Aneuploidy (PGT-A): Embryo Chromosomes and Results

Explore how PGT-A screens IVF embryos for chromosome abnormalities, what euploid, aneuploid, mosaic, and no-result findings mean, and where evidence and limits apply.

Preimplantation genetic testing for aneuploidy, or PGT-A, screens cells from an IVF embryo for extra or missing chromosomes. The test may help identify embryos...

Preimplantation Genetic Testing for Monogenic Disease (PGT-M): Inherited Disease and Results

Learn how PGT-M tests IVF embryos for a known inherited disease, including assay development, linkage, affected and carrier results, limitations, and prenatal confirmation.

Preimplantation genetic testing for monogenic disease, or PGT-M, tests IVF embryos for a specific condition caused by a variant in one gene. It can...

Preimplantation Genetic Testing for Structural Rearrangements (PGT-SR): Translocations and Results

Understand how PGT-SR tests IVF embryos from translocation or inversion carriers, including normal, balanced, unbalanced, mosaic, and inconclusive results.

Preimplantation genetic testing for structural rearrangements, or PGT-SR, examines IVF embryos for chromosome gains and losses related to a known parental translocation, inversion, or...

Prenatal Chromosomal Microarray Test: Deletions, Duplications, and Results

Prenatal chromosomal microarray testing detects fetal chromosome deletions and duplications. Learn when CMA is used, how results and VUS are interpreted, and its limits.

A prenatal chromosomal microarray test examines fetal DNA for missing or extra chromosome material, including changes too small to be seen on a standard...