Symptoms and Clinical Signs Across the Lifespan

Aromatase deficiency does not look the same for everyone. Because the condition affects how the body manages sex hormones from before birth through adulthood, the symptoms change depending on a person’s age and their chromosomal pattern (46,XX or 46,XY). This range of physical signs is known as the phenotypic spectrum ^[1]. Keep in mind that the condition is exceptionally rare; much of the evidence consists of case reports and small case series, so percentages and typical ages are possibilities, not fixed individual predictions.

Signs Before and At Birth

For many families, the first signs of aromatase deficiency appear before the baby is even born. Because the placenta cannot properly convert the baby’s androgens into estrogens, these androgens can cross back into the mother’s bloodstream ^[2].

• Maternal Virilization: During pregnancy, a mother may suddenly develop symptoms typically associated with high androgens, such as severe acne, a deepening voice, or hirsutism (unusual hair growth on the face or body) ^[1]. While symptoms like acne or hair may improve shortly after the baby is born, voice deepening or other androgen effects can persist, and maternal androgen excess warrants careful medical evaluation ^[2].
• Genital Appearance in 46,XX Infants: Most 46,XX infants with this condition are born with atypical genital development. This means the external genitals may not look clearly male or female. Doctors often use the Prader scale to describe this, with many aromatase-deficient infants falling into stages III or IV, where the features are more significantly virilized ^[1][3].

Presentation in 46,XX Individuals

As a child grows, the lack of estrogen and the buildup of other hormones create a specific pattern of symptoms:

• Delayed Puberty: Puberty often does not start on its own. While some individuals may experience some breast development (thelarche), most face primary amenorrhea (the absence of a first menstrual period) ^[3][4].
• Ovarian Cysts: In a review of reported cases, about 43% of 46,XX individuals developed large cysts on their ovaries ^[1]. These cysts can cause the ovaries to become very large and, in some cases, can lead to ovarian torsion—a medical emergency where the ovary twists on its blood supply, causing sudden, severe pain ^[5]. Ultrasound frequency is individualized.
• Hormone Markers: Lab tests typically show very high levels of FSH (Follicle-Stimulating Hormone), as the brain tries unsuccessfully to signal the body to produce estrogen ^[3].

Presentation in 46,XY Individuals

In 46,XY individuals, the diagnosis is often missed in childhood because there are rarely any unusual signs at birth. Diagnosis often happens much later, sometimes not until a person is in their 20s or 30s ^[6].

• Prolonged Growth: Without estrogen to “close” the epiphyses (the growth plates at the ends of bones), the growth plates may remain open longer than expected. This can lead to tall stature and relatively long arms and legs ^[7][8].
• Bone Health: Estrogen is vital for bone strength in all bodies. Individuals with this condition often experience early-onset osteoporosis or osteopenia (thinning bones), which can lead to easy fractures ^[9][10]. Some case reports note bone pain or leg cramps, but this is a variable finding.
• Delayed Bone Age: X-rays often show that the bones appear much “younger” than the person’s actual age because the growth plates remain open ^[7].

Metabolic and Lifestyle Factors

While not every patient experiences them, some metabolic differences have been linked to aromatase deficiency in small case series. Estrogen plays a role in how the body processes fats and sugars ^[9].

• Insulin Resistance: Some patients may have higher-than-normal blood sugar or insulin levels, which can increase the risk of Type 2 diabetes over time ^[11].
• Lipid Changes: Changes in cholesterol or triglyceride levels (dyslipidemia) can occur, though some studies have shown patients with normal profiles ^[1][9].
• Weight Management: While some reports mention weight gain or a higher body mass index, this is not a universal symptom; some individuals with the condition maintain a typical weight ^[9].

Because this condition is so rare, your specific “mix” of symptoms might be unique. Regular individualized monitoring of bone health and hormone levels by a specialist is the standard way to manage this broad spectrum of physical signs.