Inclusion Criteria:  > 18 years of age Singleton pregnancies Recruit during the first trimester and up to 22 weeks of pregnancy. Healthy subjects willing and able to provide blood, stool, vaginal swab, and breast milk samples. Must be able to provide signed and dated informed consent.  Exclusion Criteria:  Pre-pregnancy BMI greater than 40 Blood pressure SBP: > 160 mmHg -OR- DBP: > 90 mmHg Kidney disease Liver disease Anemia Symptomatic gallstones History of bariatric surgery Acute disease at time of enrollment (i.e. flu or gastroenteritis). May delay sampling until subject recovers. Chronic, clinically significant, unstable (unresolved, requiring on-going changes to medical management or medication) pulmonary, cardiovascular, gastrointestinal, hepatic or renal functional abnormality, as determined by medical history History of active uncontrolled gastrointestinal disorders or diseases including: Inflammatory bowel disease (IBD) including ulcerative colitis (mild-moderate-severe), Crohn's disease (mild-moderate-severe), or indeterminate colitis; Irritable bowel syndrome (IBS) (moderate-severe); Persistent, infectious gastroenteritis, colitis or gastritis, persistent or chronic diarrhea of unknown etiology, Clostridium difficile infection (recurrent) or Helicobacter pylori infection (untreated) Any confirmed or suspected condition/state of immunosuppression or immunodeficiency (primary or acquired) including HIV infection. Surgery of the GI tract, with the exception of cholecystectomy and appendectomy, in the past five years. Any major bowel resection at any time. Confirmed or suspected autoimmune disease  Medications:  Weight loss medications Regular high dose aspirin Regular use of prescription opiate pain medication  If taken in the past 2 months:  Systemic antibiotics, antifungals, antivirals or antiparasitics (intravenous, intramuscular or oral) Corticosteroids (intravenous, intramuscular, oral, nasal or inhaled) Cytokines Methotrexate or immunosuppressive cytotoxic agents  Diet & Lifestyle:  Recent history of chronic excessive alcohol consumption defined as more than five 1.5-ounce servings of 80 proof distilled spirits, five 12-ounce servings of beer or five 5-ounce servings of wine per day; or > 14 drinks/week. Regular/frequent use of smoking or chewing tobacco, e-cigarettes, cigars or other nicotine-containing products  Maternal chronic medical conditions:  Pre-gestational diabetes (T1 or T2) History of gestational diabetes On medication that is an immune modulators or chronic steroid use Hyperemesis gravidarum  Pregnancy history:  Preterm birth Recurrent pregnancy loss