The condition once called “true hermaphroditism” is now known in medicine as ovotesticular disorder of sex development (OT-DSD), a rare condition in which a person has both ovarian and testicular tissue in their body. It occurs in roughly 1 in 100,000 live births, making it the rarest form of all disorders of sex development in humans.1Journal of Clinical Imaging Science. Ovotesticular Disorder of Sex Development: An Unusual Presentation The old terminology has fallen out of clinical use, replaced by language that better reflects the biology involved and avoids the mythological baggage of the word “hermaphrodite.” But the condition itself remains a genuine and well-documented part of human biology, with a growing body of research shaping how clinicians approach diagnosis, treatment, and long-term care.
Why Clinicians Stopped Using the Word “Hermaphrodite”
For most of medical history, a person with both ovarian and testicular tissue was labeled a “true hermaphrodite.” That term came directly from Greek mythology and carried connotations that many patients and families found dehumanizing. In 2006, an international consensus conference formally revised the classification system for all conditions involving atypical sex development. The older labels were replaced with the broader framework of “disorders of sex development” (DSD), and “true hermaphroditism” was renamed ovotesticular DSD.2PubMed. Sex determination and disorders of sex development according to the revised nomenclature and classification in 46,XX individuals Some patient advocacy groups prefer the word “differences” over “disorders,” leading to the alternate phrasing “differences of sex development.” Both versions appear in medical literature today.
The shift was not just cosmetic. The old system grouped conditions by superficial appearance, while the new one classifies them by underlying genetics and gonadal makeup. Under the current framework, ovotesticular DSD falls within the category of disorders of gonadal development in people with a 46,XX chromosome pattern, alongside conditions like testicular DSD (formerly called “XX males”) and gonadal dysgenesis. This reorganization gives clinicians a more precise map for diagnosis and management.
What Ovotesticular DSD Actually Looks Like Inside the Body
The defining feature of OT-DSD is the confirmed presence of both ovarian tissue (containing follicles) and testicular tissue (containing seminiferous tubules) in the same person. These tissues can exist in separate gonads, so one side has an ovary and the other has a testis, or they can be combined in a single gonad called an ovotestis.3Urology. Ovotesticular Disorder of Sex Development With Mosaic 45,X/46,X,idic(Y) (q11.23) Karyotype and Streak Gonad The ovotestis is the more common arrangement.
A large study of 111 patients from South Africa examined the gonads of people with OT-DSD in detail. Of 217 total gonads biopsied, about 54% were ovotestes, with the rest split between ovaries and testes. Among the ovotestes, most were a “mixed” type where ovarian tissue formed an outer mantle wrapped around a core containing testicular tissue. A smaller fraction were “bipolar,” with ovarian and testicular zones arranged at opposite poles of the same gonad.4Journal of Pediatric Surgery. The gonads of 111 South African patients with ovotesticular disorder of sex differentiation This internal architecture matters for surgeons, because it determines whether the two tissue types can be separated without destroying functional tissue.
More recently, researchers have identified microscopic structures unique to ovotestes. In one study, about four in five ovotestis specimens contained “ovotesticular cords,” hybrid structures that blend features of the tubules found in testes with the follicular structures of ovaries.5PubMed. Ovotesticular cords and ovotesticular follicles: New histologic markers for human ovotesticular syndrome These structures may serve as reliable tissue markers for pathologists trying to confirm a diagnosis.
The Genetics Are Surprisingly Varied
You might expect that having both ovarian and testicular tissue would require an unusual mix of sex chromosomes. In practice, the majority of people with OT-DSD have a standard 46,XX karyotype, the same chromosomal makeup found in most females. Others show chimerism, with both 46,XX and 46,XY cell lines present, while a smaller number have a 46,XY karyotype or various mosaic combinations.3Urology. Ovotesticular Disorder of Sex Development With Mosaic 45,X/46,X,idic(Y) (q11.23) Karyotype and Streak Gonad A large cytogenetic study confirmed the estimated incidence of about 1 in 100,000 live births and documented the full spectrum of these chromosomal patterns.6Sexual Development. Cytogenetic Spectrum of Ovotesticular Difference of Sex Development (OT DSD) among a Large Cohort of DSD Patients and Literature Review
The question of how testicular tissue develops without a Y chromosome has driven a good deal of research. One answer involves the gene SOX9, which normally sits downstream of SRY (the gene on the Y chromosome that triggers male development). In some people with 46,XX OT-DSD, a duplication of the region around SOX9 appears to crank up its expression enough to push some gonadal tissue down the testicular pathway even without SRY being present.7PubMed Central. A Duplication Upstream of SOX9 Associated with SRY Negative 46,XX Ovotesticular Disorder of Sex Development
Another gene implicated is NR5A1, sometimes called SF1, which encodes a protein involved in gonadal development. Researchers identified a specific missense variant in NR5A1 that appeared in multiple affected family members, suggesting it can be inherited and that it alters sex development in people who carry it.8Genetics in Medicine. NR5A1 is a novel disease gene for 46,XX testicular and ovotesticular disorders of sex development These findings underscore that OT-DSD is not a single genetic event but a condition with multiple possible molecular causes, which helps explain why it presents so differently from person to person.
How It Presents and Gets Diagnosed
OT-DSD has no single look. Some individuals are identified at birth because of ambiguous genitalia. Others appear typically male or typically female at birth and are not diagnosed until puberty brings unexpected changes. A person raised male might develop breast tissue; a person raised female might experience deepening of the voice or unusual patterns of body hair. In some cases, diagnosis comes even later. One patient described in the literature did not seek medical attention until age 10, when bilateral breast development prompted a thorough exam that also revealed undescended testes and an atypical urethral opening.9Clinical Oncology and Research. Clinical Heterogenicity in Children with Ovotesticular Disorder of Sex Development
Later presentations can be particularly puzzling. Cyclic blood in the urine can occur when estrogen from ovarian tissue triggers periodic changes in the tissue around the urinary tract. Intermittent scrotal pain is another red flag, sometimes caused by the cyclic hormonal activity of ovarian tissue within an ovotestis. Testicular torsion, a surgical emergency where the gonad twists on its blood supply, has also been reported as the event that first led to diagnosis.10Pediatrics. Ovotesticular Disorder of Sex Development Presenting as a Scrotal Emergency
Confirming OT-DSD requires tissue-level proof. Hormonal blood tests and imaging studies like ultrasound can suggest the diagnosis, but they cannot definitively show that both ovarian and testicular tissue exist. Laparoscopy, a minimally invasive procedure to directly visualize and biopsy the gonads, remains the gold standard. One case report highlighted a baby with clitoral enlargement whose imaging was ambiguous; only laparoscopy and gonadal biopsy confirmed the presence of both an ovary-like streak gonad on one side and an ovotestis on the other.11PubMed Central. Endocrine Management of Ovotesticular DSD, an Index Case and Review of the Literature
Can People With Ovotesticular DSD Have Children?
This is one of the questions people find most surprising. In individuals who have functional ovarian tissue and a uterus, the answer is sometimes yes. Cyclic menstruation appears to be relatively common in girls and women with OT-DSD whose ovarian tissue remains intact.12Hormone Research in Paediatrics. Ovotesticular Difference of Sex Development: Genetic Background, Histological Features, and Clinical Management And a small number of pregnancies carried to term have been documented in the medical literature.
One particularly detailed case involved a 29-year-old woman with a 46,XX karyotype who had undergone removal of one gonad in childhood and reconstructive surgery on her vagina. Her remaining gonad functioned as an ovary, with confirmed spontaneous ovulation. Because structural narrowing of her vagina made intercourse impossible, she pursued assisted reproduction. After five unsuccessful attempts at artificial insemination, she became pregnant through in vitro fertilization and delivered a healthy boy at 37 weeks.13Journal of Nippon Medical School. Successful in Vitro Fertilization Pregnancy and Delivery by an Infertile Woman with Ovotesticular Disorder of Sex Development The authors noted this was only the eighth documented case of a live birth from a person with OT-DSD who had previously undergone gonadectomy, and the first achieved through IVF.
Fertility on the testicular side of the equation is much less well documented. Sperm production requires sustained, high-volume testosterone and specific conditions within the testicular tissue, and these are difficult to maintain in an ovotestis where ovarian tissue exerts its own hormonal influence. No confirmed cases of paternity from testicular tissue in a person with OT-DSD appear in the literature. The reproductive picture is therefore asymmetric: ovarian function can persist well enough to support pregnancy in some individuals, while testicular function rarely reaches the threshold needed for sperm production.
Tumor Risk and Why Long-Term Monitoring Matters
Whenever gonadal tissue develops atypically, there is a question about tumor risk. The good news for people with OT-DSD is that their risk appears substantially lower than that of some other DSD conditions. An updated German guideline on tumor risk across DSD groups placed ovotesticular DSD in a lower-risk category compared to conditions like complete or partial gonadal dysgenesis, where the combination of Y chromosomal material and poorly formed gonads drives higher rates of gonadal tumors.14Journal of Pediatric Urology. Tumor risk in patients with differences in sex development (DSD) statements and recommendations from the first update of the German guideline for DSD
That said, the risk is not zero. Cases of gonadoblastoma and dysgerminoma have been reported in people with OT-DSD, particularly when certain risk factors line up. These include having a 46,XY karyotype, SRY-positive cells, gonads that remain inside the abdomen rather than descending into the scrotum, and older age at diagnosis.15PubMed Central. Gonadoblastoma and Papillary Tubal Hyperplasia in Ovotesticular Disorder of Sexual Development For this reason, even though mass prophylactic gonad removal is not currently recommended for all people with OT-DSD, ongoing surveillance through imaging and hormone monitoring is considered essential, especially when any Y chromosome material is detected.
Modern Surgical Approaches
Surgery in OT-DSD has undergone a significant philosophical shift. Historically, the approach was often to remove ambiguous gonadal tissue early in life and bring the anatomy into alignment with an assigned gender. Today, the emphasis is increasingly on gonad-sparing procedures that preserve as much functional tissue as possible. In practice this means identifying and removing only the discordant tissue type while leaving the concordant tissue intact.
One technique described in the literature uses laparoscopy to perform a partial gonadectomy. The surgeon first takes a wedge biopsy for pathological confirmation, identifies the testicular component of an ovotestis based on its visual appearance, and removes it with careful dissection while preserving the surrounding ovarian tissue.16Journal of Pediatric Urology. Laparoscopic gonad-sparing procedure in Ovotesticular disorder of sex development – Case video technique The goal is twofold: to reduce the risk of unwanted hormonal effects from discordant tissue and to preserve the person’s potential for future fertility and natural hormone production.
In cases where the person is being raised male, the opposite approach applies. One report documented a scrotal emergency that turned out to be torsion of an ovotestis. Once the diagnosis was confirmed, surgeons removed the ovarian tissue and fallopian tubes from both sides while retaining the testicular tissue, epididymis, and vas deferens.10Pediatrics. Ovotesticular Disorder of Sex Development Presenting as a Scrotal Emergency Frozen pathology sections were used during the operation to map the tissue boundaries in real time, since the line between ovarian and testicular zones within an ovotestis is not always obvious to the naked eye.
The Ethics Debate Around Early Intervention
Perhaps the most contentious issue in OT-DSD care is when and whether to perform surgery on children too young to consent. A European working group identified three guiding ethical principles: fostering the well-being of the child and future adult, upholding children’s rights to participate in decisions that affect them, and respecting family relationships.17PubMed Central. Ethical principles and recommendations for the medical management of differences of sex development (DSD)/intersex in children and adolescents In practice, these principles can pull in different directions. Parents may want early clarity about their child’s body. Advocates may argue that irreversible surgery should wait until the person can weigh in themselves.
The debate has grown louder in recent years. Some activists have framed early elective genital or gonadal surgery as a violation of bodily autonomy, working with international human rights bodies to call for restrictions on procedures performed without the patient’s informed consent. Legislative efforts have appeared in several jurisdictions, including a California Senate resolution that sought to limit genital surgery on children until they could participate in decision-making.18Frontiers in Pediatrics. Navigating Surgical Decision Making in Disorders of Sex Development (DSD) On the other side, some surgical teams argue that certain procedures are medically necessary to reduce tumor risk or urological complications, and that delaying all intervention can impose its own burdens on the child, including stigma and distress during puberty.
There is no consensus yet. What has changed is the conversation itself. Multidisciplinary teams that include endocrinologists, surgeons, psychologists, ethicists, and increasingly the patients themselves are now standard at major medical centers handling DSD care. The era of a single surgeon making a unilateral decision in the delivery room is, for the most part, over.
Gender Identity and Psychosocial Experience
One widespread misunderstanding is that a person with both ovarian and testicular tissue must feel caught between male and female identities. Research tells a more nuanced story. Most people with OT-DSD develop a stable gender identity, though it does not always match the sex they were assigned at birth. In one study of pubertal outcomes, a patient who had been raised male changed to a female gender identity at age 20.19PubMed Central. Pubertal outcomes and sex of rearing of patients with ovotesticular disorder of sex development and mixed gonadal dysgenesis
A separate case report followed a patient who was initially treated with estrogen therapy, then chose to stop, was evaluated for gender dysphoria, and started testosterone. After six months, the patient stopped testosterone as well, identifying as male but opting against ongoing hormone therapy.20JCEM Case Reports. Gender Dysphoria in a Patient With Ovotesticular Disorder of Sex Development Cases like these illustrate that gender identity exploration in OT-DSD can be a winding process, and that medical teams need to be prepared for changes in direction. Rigid early commitments to a single hormonal or surgical pathway can leave a person with fewer options later.
Psychosocial support has become a recognized pillar of care. The stress of growing up with a body that does not fit neatly into social categories of male or female can affect mental health, relationships, and self-image. Access to psychological counseling, peer support networks, and age-appropriate information about one’s own condition are all considered part of comprehensive OT-DSD management today. The evidence base on long-term psychological outcomes remains thin, largely because the condition is rare enough that assembling large cohorts for study is difficult. What exists suggests that outcomes improve when patients are involved in their own care decisions from an early age and when they have access to others who share their experience.
Geographic Variation in Diagnosis Rates
The reported frequency of OT-DSD is not uniform around the world. South Africa has produced some of the largest case series, including the 111-patient study already cited, while published cases from East Asia and parts of Europe are comparatively fewer.4Journal of Pediatric Surgery. The gonads of 111 South African patients with ovotesticular disorder of sex differentiation Whether this reflects true differences in incidence, differences in how thoroughly newborns are examined, or differences in access to the kind of specialist care that leads to a confirmed diagnosis remains an open question. In many parts of the world, people with ambiguous genitalia may never receive a tissue-level diagnosis and instead live their entire lives without a clinical label. The 1 in 100,000 figure is likely an underestimate for this reason. Cases that present with a clearly male or clearly female external appearance can easily be missed unless puberty or a fertility workup reveals something unexpected.