From the Guidelines
A workup for irregular menses should begin with a comprehensive panel including thyroid-stimulating hormone (TSH), prolactin, follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol, and testosterone levels, as recommended by the most recent guidelines 1. Additionally, include a pregnancy test, complete blood count, and metabolic panel to rule out common causes. For suspected polycystic ovary syndrome (PCOS), add tests for free testosterone, sex hormone-binding globulin, dehydroepiandrosterone sulfate (DHEAS), and 17-hydroxyprogesterone, along with a transvaginal ultrasound to evaluate ovarian morphology, as suggested by recent studies 1. Hemoglobin A1c and lipid panel are important to assess metabolic status, especially in patients with suspected PCOS or type 2 diabetes 1. Timing matters - ideally collect hormone samples during the early follicular phase (days 2-5 of the cycle) if menstruation occurs. These tests help identify underlying causes such as thyroid dysfunction, hyperprolactinemia, PCOS, premature ovarian insufficiency, or structural abnormalities. The laboratory evaluation guides appropriate treatment, which may include hormonal contraceptives, metformin for PCOS, thyroid medication, or other targeted therapies based on the specific etiology identified, as recommended by recent guidelines 1. Key considerations in the workup and management of irregular menses include:
- Ruling out pregnancy and common causes of irregular menses
- Evaluating for PCOS and other endocrine disorders
- Assessing metabolic status and risk factors for cardiovascular disease
- Selecting appropriate treatment based on the underlying cause of irregular menses. Recent studies have highlighted the importance of a comprehensive workup and individualized treatment approach for patients with irregular menses, taking into account the latest evidence and guidelines 1.
From the Research
Evaluation of Irregular Menses
To evaluate irregular menses, a thorough medical history and physical examination are necessary 2. The following lab work may be considered:
- Thyroid function tests to rule out hyper- or hypothyroidism, which can cause menstrual disturbances 3
- Complete blood count (CBC) to check for anemia, which can be associated with menstrual irregularities 4
- Hormone level tests, such as follicle-stimulating hormone (FSH) and luteinizing hormone (LH), to evaluate the hypothalamic-pituitary-ovarian axis 5
- Pregnancy test to rule out pregnancy-related complications 4
Differential Diagnosis
The differential diagnosis of irregular menstrual cycles includes:
- Anovulation due to an immature hypothalamic-pituitary-ovarian axis 5
- Thyroid disorders, such as hyper- or hypothyroidism 3
- Polycystic ovary syndrome (PCOS) 4
- Other endocrine and anatomic abnormalities 5
Approach to Evaluation and Management
A stepwise approach to evaluation and management of irregular menstrual cycles is recommended, including: