Transcriptomic Evaluation of Endometrial Receptivity

Eligibility Details: Phase 1: Major Inclusion: The following are major inclusion criteria: 1. Regular menstrual cycles 2. Age 18-50 3. Normal baseline ultrasound 4. No intrauterine procedures in prior 90 days Exclusions: The following are exclusion criteria: 1. Any contraindications to undergoing estrogen stimulation of the endometrium 1. Current smoking status 2. Multiple risk factors for arterial cardiovascular disease (smoking, diabetes, and hypertension) 3. Hypertension (systolic ≥140 mmHg or diastolic ≥90 mmHg) 4. Venous thromboembolism (current or history of) 5. Known thrombogenic mutations 6. Known ischemic heart disease 7. History of stroke 8. Complicated valvular heart disease (pulmonary hypertension, risk for atrial fibrillation, history of subacute bacterial endocarditis) 9. Systemic lupus erythematosus (positive or unknown antiphospholipid antibodies) 10. Migraine with aura at any age 11. Breast cancer 12. Cirrhosis 13. Hepatocellular adenoma or malignant hepatoma 2. History of infertility diagnosis 3. History of undiagnosed abnormal uterine bleeding. 4. Allergic reaction to any medication used for the preparatory cycle 5. Known pregnancy or delivery within the past 6 months 6. Breastfeeding 7. Obesity >35 kg/m2 Phase 2 Major Inclusion: The following are major inclusion criteria: 1. Age 18-50 2. Diagnosis of infertility with low endometrial risk 3. No intrauterine procedures in prior 90 days Exclusions: In addition to the exclusion criteria for phase 1, patients deemed to have an elevated endometrial risk will also be excluded. This would include the following: 1. Recurrent implantation failure 2. Failed transfer with a euploid blastocyst 3. History of Asherman's or abnormal endometrial function 4. History of endometriosis