Last reviewed: May 12, 2026 Last updated: May 12, 2026

Written by: Jay Hastings , CEO of PlexusDx

Jay Hastings is the CEO of PlexusDx, a precision health company focused on genetic testing, blood biomarker insights, and personalized wellness recommendations. He has more than 20 years of experience across healthcare innovation, genomics, laboratory operations, healthcare investing, and strategic finance. His work has included scaling healthcare startups, leading CLIA lab integrations, and helping expand consumer access to precision health tools.

Medically reviewed by: Jayden Lee, PharmD, EMBA

Jayden Lee, PharmD, EMBA, is the PlexusDx Medical Science Liaison with a PharmD and MBA specializing in pharmacogenomics and clinical product development, with a proven ability to bridge the gap between genomic research and practical patient outcomes. Dr. Lee has more than 10 years of professional experience in clinical pharmacy, academia, and research.

This article is part of the PlexusDx Education Hub — your resource for evidence-based guidance on Hormones & Fertility. Browse all Hormones & Fertility education

Pregnenolone is the first steroid hormone your body makes from cholesterol, and every other steroid hormone — cortisol, aldosterone, DHEA, testosterone, estrogen, and progesterone — traces back to it. Because it sits at the very top of the steroid pathway, small differences in how efficiently your body produces or converts pregnenolone can ripple downstream into reproductive and sexual health. Genetics is one of several factors that shape that efficiency.

What pregnenolone actually does

Pregnenolone is synthesized inside the mitochondria of steroid-producing tissues: the adrenal glands, ovaries, testes, and brain. Researchers classify it as a neurosteroid because it acts directly on receptors in the central nervous system, influencing mood, memory, and the stress response. In the reproductive system, pregnenolone is the shared precursor that feeds both the cortisol branch and the sex-steroid branch of steroidogenesis. When production shifts, both branches can feel the effect. Levels also change naturally with age, often declining gradually from early adulthood onward, which is one reason interest in pregnenolone has grown among people focused on healthy aging.

The genes that build pregnenolone

Two genes do most of the early work. StAR (steroidogenic acute regulatory protein) shuttles cholesterol across the mitochondrial membrane — the rate-limiting first step. CYP11A1 then encodes the cholesterol side-chain cleavage enzyme that converts cholesterol into pregnenolone itself. Common variation in CYP11A1 has been studied in relation to circulating androgen levels and polycystic ovary syndrome, illustrating how a single upstream gene can influence hormones far downstream. When these genes are altered, the whole cascade that follows is affected.

Pregnenolone and reproductive health

Because pregnenolone is the raw material for progesterone, testosterone, and estrogen, its supply is closely tied to fertility, libido, and menstrual regularity. Chronic stress is one everyday example: sustained cortisol demand can draw on shared steroidogenic capacity and shift the balance of what the body prioritizes. Genetics sets the baseline efficiency of that system, while sleep, body composition, and age move it up or down over time. In women, the ovarian steroid pathway relies on the same upstream enzymes; in men, the testes depend on them for testosterone production. Because the pathway is shared, a bottleneck early on can influence hormones across the reproductive system rather than a single hormone in isolation.

When genetic variation tips the balance

The clearest example of genetics driving steroid hormones is congenital adrenal hyperplasia (CAH), most often caused by variants in the CYP21A2 gene. In CAH, an enzyme block redirects steroid precursors toward androgens, which is why pregnenolone and its metabolites are sometimes measured as part of a diagnostic workup ordered by a physician. This is a medical evaluation performed and interpreted by a qualified provider — not something a consumer test replaces. It does show, however, how a named gene variant can reshape an entire hormone profile.

What genetic insight can and cannot tell you

Understanding your genetic tendencies around steroid pathways can add useful context to conversations with your provider, but genes are only part of the story. The PlexusDx Precision Peptide Genetic Test looks at 14 pathways, 49 peptides, 150+ genetic insights, mapping how your biology may influence hormone-related and peptide-related pathways rather than diagnosing any condition. Governing principle: PlexusDx tells you about your biology; it does not tell you what to put in your body. Any decision about hormones or supplements belongs with a licensed clinician.

Frequently Asked Questions

Is pregnenolone the same as a sex hormone?

No. Pregnenolone is the precursor from which sex hormones are made. Your body converts it into progesterone, DHEA, testosterone, and estrogen through a series of enzyme steps. Because it sits upstream, changes in pregnenolone supply can indirectly influence the sex hormones produced further down the pathway.

Can genetics affect my pregnenolone levels?

Yes. Genes such as StAR and CYP11A1 govern the earliest steps of pregnenolone production, and variants in genes like CYP21A2 can redirect the pathway entirely. Genetics sets a baseline, but lifestyle, stress, age, and overall health also shape where your hormone levels actually land.

Should I take pregnenolone supplements?

That is a decision for a qualified healthcare provider. Pregnenolone supplements are not FDA-approved to treat any condition, and self-supplementing steroid precursors can shift multiple hormones at once. A clinician can evaluate whether testing or any intervention is appropriate for your specific situation.

Does the PlexusDx test diagnose a hormone disorder?

No. The Precision Peptide Genetic Test provides pathway-level educational insight into how your genes may influence hormone-related biology. It does not diagnose, treat, or manage any condition such as CAH or infertility. Diagnosis requires clinical evaluation and lab work ordered by a healthcare provider.

Curious how your genetics may shape hormone-related pathways? Explore the PlexusDx Precision Peptide Genetic Test for pathway-level insight you can bring to your provider.

This article is part of the PlexusDx Education Hub. Browse all Hormones & Fertility education

The Precision Peptide Genetic Test analyzes how your genes influence peptide-related biological pathways. It does not recommend, prescribe, or determine which peptides you should use. Consult a qualified healthcare provider before beginning any peptide protocol.

Medical and Editorial Standards

Medical review process: This article was reviewed for medical accuracy, scientific clarity, evidence alignment, and appropriate discussion of genetics, medications, supplements, biomarkers, and health-related claims.

Sources and evidence: PlexusDx educational content is developed using peer-reviewed research, clinical literature, reputable medical references, and, where applicable, public health or regulatory guidance. References are included at the end of the article when scientific, medical, or health-related claims are discussed.

Commercial transparency: PlexusDx offers genetic testing, blood biomarker testing, personalized supplement recommendations, and related precision wellness services. Product mentions are intended to help readers understand available options and should not be interpreted as medical advice.

Important disclaimer: PlexusDx educational content is for informational purposes only and should not be used as a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making decisions about medications, supplements, genetic testing, lab testing, or health-related care.