Disorders of Sexual Differentiation
At Children’s Hospital Boston, we understand that a diagnosis of a disorder of sexual differentiation (DSDs) can cause much anxiety. You probably have a lot of questions and uncertainty about your child’s sexuality and health. We’ve provided some answers to those questions here, and when you meet with our team of experts, they’ll be able to explain your child’s condition and options in more detail.
Remember that seeking out information is not only necessary but also empowering—it allows you to partner with your child’s care providers to make the best decisions for your child and your family.
What are DSDs?
- DSDs describe a wide range of conditions in which development of the sex organs does not occur as it normally would.
- These conditions involve mild to significant variations in reproductive organ development, sex development and gender identity.
- The most common DSDs are congenital adrenal hyperplasia and mixed gonadal dysgenesis
What are the different types of DSDs?
The most common DSDs detected in newborns are:
Congenital adrenal hyperplasia
- Congenital adrenal hyperplasia (CAH) genetic disorder of the adrenal glands. If your child has this condition, it means that their adrenal glands don’t produce enough of the vital hormones cortisol and aldosterone. As a result, his body produces too much androgen.
- Females born with this condition are typically born with an enlarged clitoris, but with normal internal reproductive structures.
- Males born with this condition have normal genitals at birth, but may develop a large penis, smaller testes and a deeper voice well before puberty.
- Treatment for females and may involve hormone replacement therapy, reconstructive surgery and psychological support. For males, medical treatment is indicated.
Mixed gonadal dysgensis
- Mixed gonadal dysgenesis (MGD) is a disorder of sexual differentiation in which a chromosomal abnormality causes a child to be born with two different gonads: an undescended testis and a dysgenetic (malformed) “streak” gonad.
- A child with MGD has an undescended testicle on one side and a dysgenetic (improperly developed) gonad on the opposite side. The two different gonads can’t produce normal sex hormones, resulting in malformed sex organs.
- Gender assignment is important for treatment purposes as well as the emotional well being of children as they grow older and remains a crucial part of the treatment for MGD. However, the complexity of treatment varies depending on your child’s exact anatomy.
Although less common, other types of DSDs include:
Impaired testicular development
- Impaired testicular development occurs either because of an inherited genetic defect or for an idiopathic (unknown) reason.
- Typically, a child’s body is unable to produce testosterone, which prevents the testicular structures from developing.Impaired testicular development is not the same as having an undescended testicle.
- Treatment may involve surgery. The child’s clinician will advise and work with the family on other gender and related considerations.
Androgen insensitivity syndrome (AIS):
- AIS is an inherited genetic disorder in which child is born with chromosomes and gonads (with one X chromosome and one Y chromosome), but the cells in the body do not respond to the male sex hormone androgen. As a result, the child displays female characteristics despite being genetically male.
- AIS can be either complete (in which case the child appears completely female), or incomplete (in which case, the external appearance may be ambiguous).
- Treatments can include removal of the undescended testes (to eliminate the risk of cancer) and taking estrogen replacement medication.
What causes disorders of DSDs?
Sex development starts at the time of conception and continues through late adulthood. The normal pattern of sexual development looks like this:
Chromosomes and gonads:
Gonads are the body’s primary sex organs. They form according to a specific chromosomal pattern:
- The mother’s egg and the father's sperm start out with 23 chromosomes during conception. During this time, a child inherits 23 chromosomes from each parent, ending up with a total of 46 chromosomes.
- Normally, the egg from the mother contributes one X chromosome and the sperm form the father contributes either one X chromosome or one Y chromosome.
- A child is born female if she inherits two X chromosomes (XX). A child is born male if he inherits one X chromosome and one Y chromosome (XY).
- As a result of this chromosomal pattern, boys develop gonads called testicles and females develop gonads called ovaries.
- The primary function of the gonads is producing hormones. Normally, testes produce the male hormone testosterone and ovaries produce the female hormone estrogen.
- These hormones aid in the formation of sex organs. The testosterone produced from the male testes drive the formation of a penis. The estrogen produced by female ovaries result in the formation of a vagina.
Sexual development in children with DSDs
With so many stages of sex development, there are a lot of opportunities for a fetus to take a path that not typical for a boy or a girl. When an atypical path of development is taken, the resulting condition is known as a “disorder of sexual development”.
There are several ways this can happen:
- Some disorders are genetic (chromosome variations).
- Some are present at birth (congenital) but not genetic.
- Some are variations in psychosocial development.
- DSDs can also be idiopathic, meaning they have no identifiable cause.
What are the symptoms of DSDs?
The symptoms of a DSD depend on what type of condition your child has.
- In most cases, children with DSDs have genitalia that are atypical in appearance. This may include ambiguous genitalia or dysgenetic (malformed) gonads.
- DSD can also be limited to a child’s internal structures.
What does “ambiguous genitalia” mean?
- Ambiguous genitalia refers to sexual organs that aren't well formed or aren't clearly male or female.
- At conception, a fetus's gender is already determinedbased on the23rd pairchromosome itinherited from the parents.
- Females have two X chromosomes and males have an X and a Y chromosome. Even though the gender is set, the fetal tissue that will eventually become the female ovaries or male testes (gonads) has not yet begun to take its form.
- If the hormonal process that causes that tissue to become male or female is disrupted over the following weeks, ambiguous genitalia can develop.
What causes ambiguous genitalia?
The biology behind ambiguous genitalia can be hard to understand. Breaking it down in the following steps can make it easier:
- The sexual organs of males and females develop from the same fetal tissue. The same tissue that becomes a penis in a male becomes a clitoris in a female.
- The main factor controlling the next step is male hormones. The presence of male sex hormones causes male organs to develop and the absence of male hormones causes female organs to develop.
- Without enough male hormones, a genetic male will develop ambiguous genitalia. Likewise, a genetic female will develop ambiguous genitalia if male hormone is present.
What are the symptoms of ambiguous genitalia?
Your obstetric team will most likely be the first ones who notice the ambiguous genitalia. They may see the following:
Characteristics of ambiguous genitalia in genetic females include:
- an enlarged clitoris, or what appears to be a small penis
- a concealed vagina
Characteristics of ambiguous genitalia in genetic males include:
- an abnormally small penis with the urethral opening nearer to the scrotum
- no recognizable male genitalia in the most severe cases
- the absence of both testicles in what appears to be the scrotum
What is the long-term outlook for a child with ambiguous genitalia?
With proper medical management, most children with ambiguous genitalia will lead healthy and normal lives. Sex assignment and corrective surgery are necessary in allowing your child to lead a fairly normal life as a boy or a girl. As a child grows up and enters puberty, there is a slight chance that they will identify with a sex other than the one they were assigned. In this case, a gender transition may be necessary. It’s recommended that physicians wait until the child is around 16 years old before beginning the hormone therapy process involved in a transition.
Q: What’s the difference between DSDs and “intersex disorders”?
A: DSDs used to be called “intersex disorders”. The name was changed to DSD to prevent any confusion or limiting definitions.
Q: Should my child get corrective genital surgery?
A: After your child is diagnosed with a DSD, you should have a discussion with your family and your child’s doctor about optimal management, including sex assignment. Deciding on a sex assignment depends on the anatomic findings, so it will vary from child to child.
Q: When should I consider treatment?
A: After an accurate diagnosis is made, parents discusses with your family and your child’s doctor about treatment options. Parents are encouraged to take their time when consideration treatment options and not make any immediate decisions. To avoid gender confusion, it’s best to perform corrective surgery when the child is very young. At Children’s, our doctors usually perform the reconstructive surgery when a child is about 6 months old, which reduces the risks of anesthesia.
Q: Will my child be able to have children?
A: Whether or not individuals with DSD are able to have biological children depends on what condition they have. In general, people with DSDs are not fertile or have very low fertility rates.
Q: What’s the difference between gender and sex?
A: Sex is a biological term that describes someone as being either “male” or “female”. Sex refers to sex chromosomes and sex organs.
Gender refers to attitudes, behaviors and personality characteristics that are typically associated with each sex. Gender identity is how a person identifies with masculine or feminine traits. Gender is different from sex because sometimes a person can identify with a gender that is opposite from his or her biological sex.
Q: How can I help my child?
A: Emotional support and acceptance are the best things parents can offer a child who has a DSD. Having a condition that doesn’t fit with “social norms” can be difficult, and many children with a DSD may feel ashamed or become overly focused on the appearance of their genitals. To help your child from feeling stigmatized, talk openly and honestly with him about his medical condition. Encourage him to voice any questions or concerns and avoid pushing him into a certain gender. Peer support and psychosocial counseling is key in helping children and their families come to terms with the diagnosis.
If you are having trouble coping with your child’s condition, we offer many support services that can help you to develop parenting strategies and feel less anxious.
Questions to ask your doctor
If your child has just been diagnosed with a DSD, you probably have a lot of questions on your mind before meeting with your child’s doctor. At the appointment, it can be easy to be overwhelmed with information and forget the questions you wanted to ask.
A lot of parents find it helpful to jot down questions beforehand. That way, when you talk to your child’s clinician, you can be sure that all your concerns are addressed. Remember that physicians are open to learning from families too. Attend conferences, read up on updated materials and don’t be afraid to share what you have learned.
Some questions you might ask include:
- What kind of experience do you have taking care of children with DSDs?
- What treatment plan do you recommend?
- How should I talk to my child about this condition?
- How should I explain my child’s DSD to others?
- What does my child’s long-term treatment plan involve?
- What is the follow up care plan?
- What other resources can you point me to for more information?