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PubMed This is a summary of 46 peer-reviewed journal articles Updated
Endocrinology · Swyer Syndrome

Orientation to Swyer Syndrome (46,XY Complete Gonadal Dysgenesis)

At a Glance

Swyer syndrome (46,XY complete gonadal dysgenesis) is a rare genetic condition where an individual with XY chromosomes develops typical female reproductive anatomy but non-functioning streak gonads. Treatment involves hormone replacement therapy for puberty and preventive surgery to remove streak gonads.

Receiving a diagnosis of 46,XY Complete Gonadal Dysgenesis, also known as Swyer syndrome, can be a deeply shocking and overwhelming experience [1][2]. It is often discovered during adolescence when a young woman does not start her period or shows few signs of puberty [3][2]. While the diagnosis involves genetic information that may feel confusing or contradictory to how you see yourself, it is important to know that you are female and your body has been developing as female since before you were born [4][3].

Understanding the Biology

In most people, chromosomes provide the blueprint for whether the body develops ovaries or testes. In Swyer syndrome, a change in a specific gene—such as SRY or MAP3K1—interferes with this process early in fetal development [5][6].

Because the body does not receive the signal to create testes, it does not produce the male hormones (androgens) or the “anti-female” hormone (anti-Müllerian hormone) that would typically stop female structures from growing [4][7]. As a result:

  • External appearance: You were born with a typical female body and have grown up as a girl [3][2].
  • Internal organs: You have a fully formed uterus (womb), vagina, and fallopian tubes [4][6].
  • Streak gonads: Instead of ovaries, the tissue that would have become gonads did not fully develop. These are called streak gonads—non-functional, fibrous tissue that does not produce the sex hormones needed for puberty [8][9].

Why This Diagnosis Happens

Swyer syndrome is rare, occurring in approximately 6.4 per 100,000 people [1]. The genetic changes responsible for this can sometimes be brand new (spontaneous) mutations that occur early in development, while others can be inherited from healthy, asymptomatic parents [5][10]. Either way, it is never caused by anything you or your parents did. Most young women are diagnosed because of primary amenorrhea (the medical term for never having a period) or a lack of secondary sex characteristics, such as breast development, by age 13 or 14 [3][11].

Navigating the Terminology: As you research this condition, you will likely encounter the terms Differences of Sex Development (DSD) or intersex. These are medical and community umbrella terms used to describe bodies that do not fit strictly into typical male or female physical development. Knowing these terms can help you find research and supportive communities without feeling caught off guard or alienated by the language used online [12][13].

The Path Forward

While this news is a lot to process, there is a clear and effective path for medical care that allows for a healthy, fulfilling life.

  1. Hormone Replacement Therapy (HRT): Because streak gonads do not produce estrogen, you will begin HRT. This provides the hormones your body needs to undergo puberty, develop female characteristics, and maintain strong bones [14][15][16].
  2. Preventive Surgery: Doctors recommend a prophylactic gonadectomy—the surgical removal of the streak gonads. This is necessary because these tissues have a high risk of developing tumors [17][18][19].
  3. Future Options: Although you do not produce eggs, the presence of a uterus means that pregnancy is possible in the future through assisted reproductive technology, such as using a donor egg and IVF [20][21][22].

This diagnosis does not define who you are. With the right medical management and support, young women with Swyer syndrome live healthy lives, have successful careers, and can build families of their own [14][23].

In this guide

3 chapters

01

Biology, Genetics & Diagnosis: Understanding Your Karyotype and Genes

Learn about the biology and diagnosis of Swyer syndrome (46,XY complete gonadal dysgenesis). Understand your karyotype, SRY gene testing, and hormone levels.

02

Standard of Care: Surgery and Hormone Therapy

Learn about the standard of care for Swyer syndrome (46,XY gonadal dysgenesis), including prophylactic gonadectomy and hormone replacement therapy (HRT).

03

Long-Term Outlook: Fertility, Bone Health, and Survivorship

Learn about the long-term outlook for Swyer syndrome, including sexual health, protecting bone density with HRT, and future fertility options like IVF.

Common questions in this guide

What causes Swyer syndrome?
Swyer syndrome occurs when a genetic change, such as a mutation in the SRY or MAP3K1 gene, interrupts sex development before birth. This prevents testes from forming, leading the body to develop female external characteristics and internal organs, but without functioning ovaries.
Will I ever get a period with Swyer syndrome?
Because your body has underdeveloped streak gonads instead of functioning ovaries, you will not get a period naturally. However, once you begin hormone replacement therapy, your doctor can help you establish a regular menstrual cycle.
Why do I need surgery for my streak gonads?
Doctors strongly recommend prophylactic gonadectomy, which is the surgical removal of the streak gonads. This preventive surgery is necessary because these non-functioning tissues have a high risk of developing tumors over time.
Can women with Swyer syndrome get pregnant?
Yes, pregnancy is possible. Because individuals with Swyer syndrome have a fully formed uterus, you can carry a pregnancy with the help of assisted reproductive technologies, such as using a donor egg and in vitro fertilization (IVF).
What does a DSD diagnosis mean?
DSD stands for Differences of Sex Development, a medical term used to describe physical development that doesn't fit strictly into typical male or female patterns. Swyer syndrome is considered a DSD because it involves the presence of XY chromosomes in a female body.

Questions to Ask Your Doctor

Curated prompts to bring to your next appointment.

  1. 1.Which specific gene was involved in my diagnosis, and does it indicate this was spontaneous or inherited?
  2. 2.What is the timeline for my prophylactic gonadectomy?
  3. 3.Are there support groups or other patients with a DSD diagnosis that you can connect me with?
  4. 4.Who will be the primary coordinator of my multidisciplinary care team?
  5. 5.Can you explain how this diagnosis was confirmed and walk me through the lab results?

Questions For You

Tap a prompt to share your answer — we'll use it plus this page's context to start a tailored conversation.

References

References (23)
  1. 1

    Incidence, Prevalence, Diagnostic Delay, and Clinical Presentation of Female 46,XY Disorders of Sex Development.

    Berglund A, Johannsen TH, Stochholm K, et al.

    The Journal of clinical endocrinology and metabolism 2016; (101(12)):4532-4540 doi:10.1210/jc.2016-2248.

    PMID: 27603905
  2. 2

    Late presentation of Swyer syndrome: A case report.

    Pathak S, Raj G, Pratap R, Singh S

    Radiology case reports 2023; (18(9)):3295-3298 doi:10.1016/j.radcr.2023.06.061.

    PMID: 37497464
  3. 3

    A Case of Primary Amenorrhea with Swyer Syndrome.

    Priya PK, Mishra VV, Choudhary S, Rizvi JS

    Journal of human reproductive sciences 2017; (10(4)):310-312 doi:10.4103/jhrs.JHRS_128_17.

    PMID: 29430160
  4. 4

    Swyer Syndrome: A diagnostic challenge.

    Bannour I, Bannour B, Ferjani S, Boughizane S

    JBRA assisted reproduction 2025; (29(1)):195-198 doi:10.5935/1518-0557.20240096.

    PMID: 40073224
  5. 5

    Identification of a novel mutation (Ala66Thr) of SRY gene causes XY pure gonadal dysgenesis by affecting DNA binding activity and nuclear import.

    Wang X, Xue M, Zhao M, et al.

    Gene 2018; (651()):143-151 doi:10.1016/j.gene.2018.01.076.

    PMID: 29378242
  6. 6

    A novel missense heterozygous mutation in MAP3K1 gene causes 46, XY disorder of sex development: case report and literature review.

    Al Shamsi A, Al Hassani N, Hamchou M, et al.

    Molecular genetics & genomic medicine 2020; (8(11)):e1514 doi:10.1002/mgg3.1514.

    PMID: 32986312
  7. 7

    A novel SRY gene mutation c.266 A>T (p.E89V) in a 46,XY complete gonadal dysgenesis patient.

    Raveendran SK, Ramachandran L, Joseph L, et al.

    Andrologia 2019; (51(9)):e13377 doi:10.1111/and.13377.

    PMID: 31361042
  8. 8

    Swyer Syndrome with Heterotopic Adrenal Cortical Tissue in Streak Gonads: A Rare Case and Review of Literature.

    Goyal M, Batra S, Singh P, et al.

    Journal of human reproductive sciences 2019; (12(4)):345-347 doi:10.4103/jhrs.JHRS_44_19.

    PMID: 32038087
  9. 9

    Clinical Presentation and Management of Swyer Syndrome: A Case Report.

    Errahali Y, Malad M, Lakssir I, et al.

    Cureus 2026; (18(1)):e100735 doi:10.7759/cureus.100735.

    PMID: 41646581
  10. 10

    Identification of NR5A1 Mutations and Possible Digenic Inheritance in 46,XY Gonadal Dysgenesis.

    Mazen I, Abdel-Hamid M, Mekkawy M, et al.

    Sexual development : genetics, molecular biology, evolution, endocrinology, embryology, and pathology of sex determination and differentiation 2016; (10(3)):147-51 doi:10.1159/000445983.

    PMID: 27169744
  11. 11

    Gonadoblastoma in a patient with 46, XY complete gonadal dysgenesis.

    Keskin M, Savaş-Erdeve Ş, Kurnaz E, et al.

    The Turkish journal of pediatrics 2016; (58(5)):538-540.

    PMID: 28621097
  12. 12

    Molecular mechanisms underlying the defects of two novel mutations in the HSD17B3 gene found in the Tunisian population.

    Ben Rhouma B, Kley M, Kallabi F, et al.

    The Journal of steroid biochemistry and molecular biology 2023; (227()):106235 doi:10.1016/j.jsbmb.2022.106235.

    PMID: 36563763
  13. 13

    Disorders/Differences of Sex Development Presenting in the Newborn With 46,XY Karyotype.

    Bertelloni S, Tyutyusheva N, Valiani M, et al.

    Frontiers in pediatrics 2021; (9()):627281 doi:10.3389/fped.2021.627281.

    PMID: 33968844
  14. 14

    Pure 46, XY gonadal dysgenesis and 46, XY complete androgen insensitivity syndrome: A case report.

    Yu T, Liu L

    Medicine 2024; (103(25)):e38297 doi:10.1097/MD.0000000000038297.

    PMID: 38905377
  15. 15

    The Mysteries of Primary Amenorrhea: Swyer Syndrome.

    Cherukuri S, Jajoo SS, Dewani D, Andela M

    Cureus 2022; (14(8)):e28170 doi:10.7759/cureus.28170.

    PMID: 36158407
  16. 16

    Two successful pregnancies after in vitro fertilisation with oocyte donation in a patient with Swyer syndrome - a case report.

    Urban A, Knap-Wielgus W, Grymowicz M, Smolarczyk R

    Przeglad menopauzalny = Menopause review 2021; (20(3)):158-161 doi:10.5114/pm.2021.109361.

    PMID: 34703418
  17. 17

    Gonadal tumor risk in pediatric and adolescent phenotypic females with disorders of sex development and Y chromosomal constitution with different genetic etiologies.

    Lu L, Luo F, Wang X

    Frontiers in pediatrics 2022; (10()):856128 doi:10.3389/fped.2022.856128.

    PMID: 35935368
  18. 18

    Germ Cell Tumors in 46, XY Gonadal Dysgenesis.

    Misgar RA, Islam Mir SU, Mir MH, et al.

    Indian journal of endocrinology and metabolism 2024; (28(4)):424-428 doi:10.4103/ijem.ijem_373_22.

    PMID: 39371651
  19. 19

    Advanced-Stage Gonadal Dysgerminoma in a Patient With a Previous Diagnosis of Familial Swyer Syndrome: A Very Rare Genetic Entity.

    Oğlak SC, Söğütçü N, Akgöl S, et al.

    Case reports in medicine 2026; (2026()):3312911 doi:10.1155/carm/3312911.

    PMID: 41551439
  20. 20

    Infertility management in a patient with Swyer syndrome: a case report.

    Krygere L, Bartasiene R, Kozlovskaja-Gumbriene A, Drejeriene E

    Journal of assisted reproduction and genetics 2025; (42(5)):1689-1695 doi:10.1007/s10815-025-03442-4.

    PMID: 40097859
  21. 21

    Rare successful pregnancy in a patient with Swyer Syndrome.

    Taneja J, Ogutu D, Ah-Moye M

    Case reports in women's health 2016; (12()):1-2 doi:10.1016/j.crwh.2016.10.001.

    PMID: 29629300
  22. 22

    A Successful New Case of Twin Pregnancy in a Patient with Swyer Syndrome-An Up-to-Date Review on the Incidence and Outcome of Twin/Multiple Gestations in the Pure 46,XY Gonadal Dysgenesis.

    Winkler I, Jaszczuk I, Gogacz M, et al.

    International journal of environmental research and public health 2022; (19(9)) doi:10.3390/ijerph19095027.

    PMID: 35564421
  23. 23

    Perspective on postoperative hormone replacement therapy and fertility preservation in Swyer syndrome with dysgerminoma: a case series and literature review.

    Liang J, Wu T, Feng X, et al.

    European journal of obstetrics, gynecology, and reproductive biology 2026; (317()):114857 doi:10.1016/j.ejogrb.2025.114857.

    PMID: 41317609

This page provides educational information about Swyer syndrome and its biological mechanisms. It does not replace professional medical advice, diagnosis, or treatment planning from your endocrinologist or multidisciplinary care team.

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