nutritional deficits It should be noted that diagnosis of stress as the cause of oligomenorrhea is one of exclusion Pseudocyesis is a rare cause of amenorrhea in women who believe they are pregnant and who exhibit many presumptive symptoms and signs of pregnancy, including nausea, vomiting, hyperpigmented areolae, galactorrhea, and abdominal distension The diagnosis is made when a patient who insists that she is pregnant nevertheless has no true uterine enlargement, no demonstrable fetal parts or heart sounds, and a negative pregnancy test result Psychiatric consultation should be obtained for such patients APPROACH TO DIAGNOSIS Patients with oligomenorrhea but few other symptoms or signs of disease may require laboratory evaluation to differentiate among the many potential causes of oligomenorrhea after pregnancy has been excluded This workup is usually done in an outpatient setting Figure 51.1 outlines a strategy for initial emergency diagnostic evaluation Helpful labs to be obtained in the ED include TSH and prolactin An elevated TSH level points to hypothyroidism either as the cause of oligomenorrhea or as a concomitant condition while a low TSH could point to hyperthyroidism An elevated prolactin level suggests a pituitary adenoma in nonbreastfeeding patients who are not taking any of the drugs known to cause hyperprolactinemia and galactorrhea ( Table 51.3 ) For the purposes of the emergency clinician, once pregnancy and life-threatening causes are ruled out, patients can be referred to their primary care physician, adolescent physician, or gynecologist for further evaluation If an Emergency Provider were to send additional labs to assist in the outpatient workup, the following would be helpful: LH, FSH, free and total testosterone levels The finding of a mildly elevated total or free testosterone level constitutes strong evidence for a diagnosis of PCOS A total testosterone level of more than 200 ng per dL suggests an ovarian or adrenal tumor FSH values of more than 40 mIU per mL confirm ovarian failure If the laboratory evaluation discloses no abnormalities or only a low FSH level, the patient likely has one of the many conditions that cause hypothalamic–pituitary suppression