From the Guidelines
Laboratory tests for evaluating low libido in women should include hormone panels such as estrogen, testosterone, progesterone, thyroid hormones (TSH, T3, T4), prolactin, and DHEA-S, as well as complete blood count and comprehensive metabolic panel to rule out underlying medical conditions. When evaluating low libido in women, it is essential to consider the potential physiological causes, including hormonal imbalances. According to the most recent guideline update 1, evaluation of hormonal deficiencies, including FSH and estrogen in premenopausal females with fatigue, loss of libido, and mood changes, or oligomenorrhea, is crucial.
Some key laboratory tests to consider include:
- Thyroid-stimulating hormone level (thyroid disease)
- Prolactin level (hyperprolactinemia)
- Total testosterone or bioavailable or free testosterone levels (ovarian hyperandrogenism) 1
- Fasting lipid and lipoprotein levels (dyslipidemia)
- Complete blood count and comprehensive metabolic panel to rule out anemia, liver or kidney dysfunction, and other medical conditions that might contribute to low desire.
It is also important to note that normal lab values do not rule out sexual dysfunction, as psychological, relationship, and other factors often play significant roles in female sexual desire. Therefore, a comprehensive evaluation, including laboratory tests and assessment of psychological and relationship factors, is necessary to determine the underlying causes of low libido in women.
From the Research
Labs for Low Libido in Women
To diagnose low libido in women, several laboratory tests can be conducted to rule out underlying hormonal imbalances. Some of the key hormones that are typically tested include:
- Follicle-stimulating hormone (FSH)
- Luteinizing hormone (LH)
- Estradiol
- Prolactin
- Testosterone
Hormonal Reference Ranges
The reference ranges for these hormones can vary significantly across different laboratories 2. For example, the upper limit of normal reference ranges for FSH, LH, estradiol, and prolactin can range from 7.9-20.0,4.9-86.5,37.7-77.0, and 7.4-25.0, respectively. It is essential to note that these reference ranges are often based on small population studies and may not account for factors such as age, race, and medical history.
Hormonal Fluctuations During the Menstrual Cycle
Hormonal levels can fluctuate throughout the menstrual cycle, and understanding these changes is crucial for accurate diagnosis and treatment 3. For instance, plasma endothelin-1 and endothelin-3 levels have been shown to fluctuate during the menstrual cycle, with a peak at the luteal phase. Additionally, these hormones have been found to have a negative relationship with prolactin and a positive correlation with atrial natriuretic peptide (ANP) during the entire menstrual cycle.
Laboratory Testing
Laboratory testing for low libido in women typically involves measuring the levels of various hormones in the blood and urine. The tests may include:
- FSH and LH levels to evaluate ovarian function
- Estradiol levels to assess estrogen production
- Prolactin levels to rule out hyperprolactinemia
- Testosterone levels to evaluate androgen production
- Thyroid function tests to rule out hypothyroidism or hyperthyroidism
It is essential to consult with a healthcare provider to determine the appropriate laboratory tests and interpretation of results, as the diagnosis and treatment of low libido in women can be complex and multifaceted 2, 3.