Subjective: Patient presents with amenorrhea, defined as the absence of menses.  Chief complaint is a missed period.  Patient reports her last menstrual period (LMP) was [Date or duration, e.g., 8 weeks ago, October 26, 2023].  Patient's usual menstrual cycle is [Frequency and duration, e.g., regular, every 28 days, lasting 5 days] with [Flow description, e.g., normal flow].  Patient denies any abnormal vaginal bleeding or spotting.  Review of systems includes inquiry regarding pregnancy symptoms such as nausea, vomiting, breast tenderness, fatigue, and urinary frequency.  Patient reports [Presence or absence of these symptoms].  Further history includes questions regarding stress levels, recent weight changes, dietary habits, exercise routines, and use of medications, including hormonal contraceptives, which could contribute to secondary amenorrhea.  Patient denies history of eating disorders, thyroid problems, or polycystic ovary syndrome (PCOS).

Objective:  Vital signs stable.  Physical examination, including pelvic exam if age-appropriate and clinically indicated, reveals [Findings, e.g., normal external genitalia, uterus non-tender, no adnexal masses].  Pregnancy test [Positive, negative, or pending].

Assessment:  Missed period, differential diagnosis includes pregnancy, secondary amenorrhea due to [Potential causes based on history and physical, e.g., stress, weight changes, medication use], or primary amenorrhea if the patient has never menstruated and is of appropriate age for menarche.  Further investigation may be required to exclude other potential causes such as hypothalamic dysfunction, pituitary adenoma, premature ovarian insufficiency, or other endocrine disorders.  ICD-10 code [N91.0, N91.1, or other appropriate code based on clinical findings].

Plan:  Based on initial evaluation, the plan includes [Ordered tests, e.g., serum human chorionic gonadotropin (hCG) level, complete blood count (CBC), thyroid stimulating hormone (TSH), prolactin level, follicle-stimulating hormone (FSH), luteinizing hormone (LH)].  If pregnancy is confirmed, appropriate obstetric referral will be made.  If pregnancy is ruled out, further evaluation will be based on the results of the laboratory tests and may include imaging studies such as pelvic ultrasound or referral to a gynecologist or endocrinologist for further management of secondary amenorrhea. Patient education provided regarding menstrual cycle irregularities, potential causes of amenorrhea, and the importance of follow-up. Return for follow-up in [Duration] to discuss results and next steps.