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Test ID: 17PRN Pregnenolone and 17-Hydroxypregnenolone, Serum

Reporting Name

Pregnenolone and 17-OH Pregnenolone

Useful For

An ancillary test for congenital adrenal hyperplasia (CAH), particularly in situations in which a diagnosis of 21-hydroxylase and 11-hydroxylase deficiency have been ruled out


Confirming a diagnosis of 3-beta-hydroxysteroid dehydrogenase deficiency and 17-alpha-hydroxylase deficiency


As part of a battery of tests to evaluate women with hirsutism or infertility; both can result from adult-onset CAH

Clinical Information

Congenital adrenal hyperplasia (CAH) is caused by inherited defects in steroid biosynthesis. Deficiencies in several enzymes cause CAH including 21-hydroxylase (CYP21A2 variants; 90% of cases), 11-hydroxylase (CYP11A1 variants; 5%-8%), 3-beta-hydroxysteroid dehydrogenase (3-beta-HSD) (HSD3B2 variants; <5%), and 17-alpha-hydroxylase (CYP17A1 variants; 125 cases reported to date). The resulting hormone imbalances (reduced glucocorticoids and mineralocorticoids; and elevated steroid intermediates and androgens) can lead to life-threatening, salt-wasting crises in the newborn period and incorrect gender assignment of virilized females.


The adrenal glands, ovaries, testes, and placenta produce steroid intermediates, which are hydroxylated at position 21 (by 21-hydroxylase) and position 11 (by 11-hydroxylase) to produce cortisol. Deficiency of either 21-hydroxylase or 11-hydroxylase results in decreased cortisol synthesis and loss of feedback inhibition of adrenocorticotropic hormone (ACTH) secretion. The consequent increased pituitary release of ACTH drives increased production of steroid intermediates.


The steroid intermediates are oxidized at position 3 (by 3-3-beta-HSD). The 3-beta-HSD enzyme allows formation of 17-hydroxyprogesterone (17-OHPG) from 17-hydroxypregnenolone and progesterone from pregnenolone. When 3-beta-HSD is deficient, cortisol is decreased, 17-hydroxypregnenolone and pregnenolone levels may increase, and 17-OHPG and progesterone levels, respectively, are low. Dehydroepiandrosterone is also converted to androstenedione by 3-beta-HSD and may be elevated in patients affected with 3-beta-HSD deficiency.


The best screening test for CAH, most often caused by either 21- or 11-hydroxylase deficiency, is the analysis of 17-hydroxyprogesterone (along with cortisol and androstenedione). CAH21 / Congenital Adrenal Hyperplasia (CAH) Profile for 21-Hydoxylase Deficiency, Serum allows the simultaneous determination of these 3 analytes. Alternately, these tests may be ordered individually: OHPG / 17-Hydroxyprogesterone, Serum; CINP / Cortisol, Mass Spectrometry, Serum; and ANST / Androstenedione, Serum.


If both 21- and 11-hydroxylase deficiency have been ruled out, analysis of 17-hydroxypregnenolone and pregnenolone may be used to confirm the diagnosis of 3-beta-HSD or 17-alpha-hydroxylase deficiency.


For more information see Steroid Pathways.


The diagnosis and differential diagnosis of congenital adrenal hyperplasia (CAH) always require the measurement of several steroids. Patients with CAH due to steroid 21-hydroxylase gene (CYP21A2) variants usually have very high levels of androstenedione, often 5-fold to 10-fold elevations. 17-Hydroxyprogesterone (17-OHPG) levels are usually even higher, while cortisol levels are low or undetectable. All 3 analytes should be tested.


For the HSD3B2 variant, cortisol, 17-OHPG, and progesterone levels will be decreased; 17-hydroxypregnenolone, pregnenolone, and DHEA levels will be increased.


In the much less common CYP11A1 variant, androstenedione levels are elevated to a similar extent as seen in CYP21A2 variant, and cortisol also is low, but 17-OHPG is only mildly, if at all, elevated.


In the very rare 17-hydroxylase deficiency, androstenedione, all other androgen-precursors (17-alpha-hydroxypregnenolone, 17-OHPG, dehydroepiandrosterone sulfate), androgens (testosterone, estrone, estradiol), and cortisol are low, while production of mineral corticoid and its precursors (in particular pregnenolone, 11-dexycorticosterone, corticosterone, and 18-hydroxycorticosterone) are increased.


For more information see Steroid Pathways.

Testing Algorithm

For information see Steroid Pathways.

Profile Information

Test ID Reporting Name Available Separately Always Performed
PREGN Pregnenolone, S Yes Yes
17OHP 17-Hydroxypregnenolone, S Yes Yes

Special Instructions

Report Available

3 to 6 days

Day(s) Performed

Monday, Wednesday, Friday

Clinical Reference

1. Wudy SA, Hartmann M, Svoboda M: Determination of 17-hydroxyprogesterone in plasma by stable isotope dilution/benchtop liquid chromatography-tandem mass spectrometry. Horm Res. 2000;53(2):68-71

2. Therrell BL: Newborn screening for congenital adrenal hyperplasia. Endocrinol Metab Clin North Am. 2001 Mar;30(1):15-30

3. Bachega TA, Billerbeck AE, Marcondes JA, et al: Influence of different genotypes on 17-hydroxyprogesterone levels in patients with nonclassical congenital adrenal hyperplasia due to 21-hydroxylase deficiency. Clin Endocrinol. 2000 May;52(5):601-607

4. Kao PC, Machacek DA, Magera MJ, at al: Diagnosis of adrenal cortical dysfunction by liquid chromatography-tandem mass spectrometry. Ann Clin Lab Sci. 2001 Apr;31(2):199-204

5. Sciarra F, Tosti-Croce C, Toscano V: Androgen-secreting adrenal tumors. Minerva Endocrinol. 1995 Mar;20(1):63-68

6. Collett-Solberg PF: Congenital adrenal hyperplasia: from genetics and biochemistry to clinical practice, part I. Clin Pediatr (Phila). 2001 Jan:40(1):1-16

7. Chormanski D, Muzio MR: C 17 hydroxylase deficiency. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing LLC; 2021. Updated July 19, 2021. Accessed October 21, 2022. Available at

Method Name

Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

Portions of this test are covered by patents held by Quest Diagnostics

Specimen Type


Specimen Required

Collection Container/Tube:

Preferred: Red top

Acceptable: Serum gel

Submission Container/Tube: Plastic vial

Specimen Volume: 1 mL

Collection Instructions: Centrifuge and aliquot serum into plastic vial.

Specimen Minimum Volume

0.5 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Serum Frozen 28 days

Reference Values




0-6 years: Not established

7-9 years: <206 ng/dL

10-12 years: <152 ng/dL

13-15 years: 18-197 ng/dL

16-17 years: 17-228 ng/dL

Tanner Stages

Stage I: <157 ng/dL

Stage II: <144 ng/dL

Stage III: <215 ng/dL

Stage IV-V: 19-201 ng/dL



0-6 years: Not established

7-9 years: <151 ng/dL

10-12 years: 19-220 ng/dL

13-15 years: 22-210 ng/dL

16-17 years: 22-229 ng/dL

Tanner Stages

Stage I: <172 ng/dL

Stage II: 22-229 ng/dL

Stage III: 34-215 ng/dL

Stage IV-V: 26-235 ng/dL



≥18 years: 33-248 ng/dL





Premature (26-28 weeks): 1,219-9,799 ng/dL

Premature (29-36 weeks): 346-8,911 ng/dL

Full term (1-5 months): 229-3,104 ng/dL

6 months-364 days: 221-1,981 ng/dL

1-2 years: 35-712 ng/dL

3-6 years: <277 ng/dL

7-9 years: <188 ng/dL

10-12 years: <393 ng/dL

13-15 years: 35-465 ng/dL

16-17 years: 32-478 ng/dL

Tanner Stages

Stage I: <209 ng/dL

Stage II: <356 ng/dL

Stage III: <451 ng/dL

Stage IV-V: 35-478 ng/dL



Premature (26-28 weeks): 1,219-9,799 ng/dL

Premature (29-36 weeks): 346-8,911 ng/dL

Full term (1-5 months): 229-3,104 ng/dL

6 months-364 days: 221-1,981 ng/dL

1-2 years: 35-712 ng/dL

3-6 years: <277 ng/dL

7-9 years: <213 ng/dL

10-12 years: <399 ng/dL

13-15 years: <408 ng/dL

16-17 years: <424 ng/dL

Tanner Stages

Stage I: <236 ng/dL

Stage II: <368 ng/dL

Stage III: <431 ng/dL

Stage IV-V: <413 ng/dL




≥18 years: 55-455 ng/dL


≥18 years: 31-455 ng/dL


*Kushnir MM, Rockwood AL, Roberts WL, et al: Development and performance evaluation of a tandem mass spectrometry assay for 4 adrenal steroids. Clin Chem. 2006 Aug;52(8):1559-1567


To convert to nmol/L, multiply the value in ng/dL by 0.03159757.

Test Classification

This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information



LOINC Code Information

Test ID Test Order Name Order LOINC Value
17PRN Pregnenolone and 17-OH Pregnenolone In Process


Result ID Test Result Name Result LOINC Value
81151 17-Hydroxypregnenolone, S 6765-2
88645 Pregnenolone, S 2837-3
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