Can diet and activity classes help Moms-to-Be avoid excess weight gain?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

* INCLUSION CRITERIA: Adult pregnant women of any race or ethnicity may participate if they meet each of the following inclusion criteria: 1. At least 18 years of age. 2. Receive prenatal care at the nurse midwifery/obstetrics service of PIMC and plan to continue receiving such care throughout the pregnancy. 3. Able to have an OGTT prior to 16 weeks gestation. Hyperemesis can preclude some pregnant women from successfully completing the OGTT; these women will not be excluded if the fasting blood samples can be obtained. 4. Able to have an ultrasound examination to estimate fetal age. 5. Complete initial run-in screening visits to determine whether the woman can manage the tasks required of participation in an intensive intervention if randomized to the intervention group. 6. Able to commit the time required for the interventions and follow-up. 7. Singleton viable pregnancy. A twin pregnancy reduced to singleton before 14(0) weeks by project gestational age is acceptable. An ultrasound must be conducted before randomization that shows a fetal heartbeat; there should be no evidence of more than one fetus on the most recent pre-randomization ultrasound. 8. Gestational age at randomization no earlier than 9 weeks 0 days and no later than 15(6) weeks based on an algorithm that compares the LMP date and data from the earliest ultrasound. 9. Body mass index greater than or equal to 25 kilogram / square meter based on first trimester measured weight and on measured height. The earliest weight measurement before randomization, measured specifically for the study, will be used. Reported pre-pregnancy weight will not be used to determine eligibility because of the potential for inaccuracy. If the earliest weight measurement is conducted at 14(0) to 14(6) weeks or 15(0) to 15(6) weeks, 1 pound or 2 pounds will be subtracted from the measured weight, respectively, to adjust to a first trimester weight. This weight and the resultant BMI are defined as the baseline weight and BMI, respectively. EXCLUSION CRITERIA: * Diagnosis of diabetes prior to pregnancy or any of the following results of the oral glucose tolerance test at visit #1 that suggest diabetes prior to pregnancy: HbA1c greater than or equal 6.5 %, FPG greater than or equal 126 milligrams per deciliter, or 2-hour post-load plasma glucose greater than or equal 200 milligrams per deciliter (75 grams oral glucose tolerance test). All potential participants will have HbA1c and a 75 grams oral glucose tolerance test performed prior to randomization. * Women who meet the above criteria for diagnosed or presumed diabetes prior to pregnancy will be excluded. Others who meet criteria for GDM will be eligible. Criteria for GDM diagnosis will be based on ADA 2012 criteria (at least one of FPG greater than or equal to 92 milligrams per deciliter, 1 hour PG greater than or equal 180 milligrams per deciliter, or 2 hour PG greater than or equal to 153 milligrams per deciliter.) * Known fetal anomaly * Planned termination of pregnancy * History of three or more consecutive first trimester miscarriages * Past history of anorexia or bulimia by medical history or patient report. Binge eating disorder (BED) is not an exclusion. * Current eating disorder diagnosed by EDE-Q questions 2-4 and confirmed after discussion with the participant by study staff * Actively suicidal defined as a value greater than or equal 2 on the BDI-II question 9 * Prior or planned (within 1 year of expected delivery) bariatric surgery * Current use of one or more of the following medications: * Metformin * Systemic steroids * Antipsychotic agents (e.g., Abilify (apriprazole), Haldol (haloperidol), Risperdal (resperidone), Seroquel (quetipapine), Zyprexa (olanzapine)) * Anti-seizure medications or mood stabilizers that would be expected to have a significant impact on body weight (e.g., Depakote (valproic acid), Lamictal (lamotrigine), Lithium, Neurontin (gabapentin), Tegretol (carbamazepine), Topamax (topiramate), Keppra (levetiracetam) * Medications for ADHD including amphetamines and methylphenidate * Any teratogenic agent Class D or X (site specific) * Continued use of weight loss medication including OTC and dietary supplements for weight loss (e.g., Adipex (phentermine), Suprenza(phentermine) Tenuate (dietheylpropion), Xenical (orlistat), Alli (orlistat), conjugated linoleic acid, Hoodia, Green tea extract, Guar gum, HydroxyCut, Sensa, Corti-slim, Chromium, chitosan, Bitter orange) * Contraindications to aerobic exercise in pregnancy specified in the ACOG Committee Opinion #267, 2002 * Hemodynamically significant heart disease defined as an AHA class II (short of breath with exercise) or greater * Restrictive lung disease (e.g. pulmonary fibrosis) * Poorly controlled hyperthyroidism * Poorly controlled seizure disorder * Poorly controlled hypertension defined as a blood pressure greater than or equal 160/110 millimeters of mercury * History of extreme sedentary lifestyle (e.g. bed bound) * Orthopedic limitations to aerobic exercise * Severe anemia defined as a hemoglobin less than 8 grams per deciliter * Any condition that requires follow-up at specialty care clinics outside of PIMC (e.g., pregnancies at high risk for maternal or fetal demise) * Participation in another interventional study that influences weight control * Enrollment in this trial in a previous pregnancy * Intention of the participant or of the care provider for the delivery to be outside the greater Phoenix metropolitan area. * Participant s unwillingness or inability to commit to a 1 year follow-up of herself or her child, including planning to move away. * Inability or unwillingness to provide informed consent, in the English language, including consent for study staff to abstract data from all prenatal and delivery records (for the current pregnancy) whether the care or delivery occur at PIMC or elsewhere. English is the common language of the participants who receive care at PIMC. Some also speak tribal languages or Spanish. English is the language used in the intervention materials, the screening forms, and online documents. English is also the primary language of study staff. * Any condition that in the opinion of the investigators would interfere with consent, treatment or follow-up.