The Role of Estrogen in the Neurobiology of Eating Disorders

Inclusion criteria:

• Female

• 14-35 years

• Bone age ≥13.5 years (applicable only for participants <16 years)

• Clinically significant eating disorder characterized by restriction and/or excessiveexercise and high drive for thinness

• Hypoestrogenemia: Oligo-amenorrhea defined as lack of menses for ≥3 months within a 6-month period of oligomenorrhea (cycle length ≥5 weeks) or absence of menses at >15years if premenarchal or low estradiol levels evaluated by the study physician

• Low or normal weight defined by a body mass index that is <85th percentile for 14-18year olds and a body mass index <25 kg/m2 for adults

Exclusion criteria:

• Suicidal ideation where outpatient treatment is determined unsafe by study clinician

• Other causes of oligo-amenorrhea, unless a study clinician determines that missedmenstrual periods are more likely a consequence of restrictive eating

• Medications that contain estrogen ± progesterone within the past 3 months

• Levonorgestrel-releasing intrauterine device if subject is unable to provide two tothree weekly blood samples for estradiol of if estradiol levels are determined to betoo high by study doctor

• Neurological or psychiatric disorders that may impact neural circuitry of interest

• Lifetime history of seizure disorder or electroconvulsive therapy

• Pregnancy/breastfeeding

• Gastrointestinal tract surgery

• Contraindications to estrogen use

• Any other significant illness or condition that the investigator determines couldinterfere with study participation or safety or put the subject at any unnecessaryrisk