Eligibility |
- INCLUSION CRITERIA for eligible subjects in the SINGLETON study:
- Singleton, viable pregnancy
- 8^(+0) - 13^(+6) weeks of gestation
- Maternal age 18 - 40 years
- BMI 19.0 - 29.9 kg/m(2) for low risk group; BMI 30.0 -45.0 kg/m(2) for obese group
- Firm LMP
- LMP-date and ultrasound date match within 5 days for gestation estimates between 8
weeks + 0 days and 10 weeks + 6 days, 6 days for those between 11 weeks + 0 days and
12 weeks + 6 days, and 7 days for estimates between 13 weeks + 0 days and 13 weeks + 6
days
- No confirmed or suspected fetal congenital structural or chromosomal anomalies
- Expect to deliver at one of the participating hospitals
- No previous participation in the NICHD Fetal Growth Study
EXCLUSION CRITERIA for eligible subjects in the SINGLETON study:
The following criteria apply only to non-obese women:
- Smoked cigarettes in the past six months
- Used illicit drugs in the past year
- Having at least 1 alcoholic drink per day
- Conception by ovulation stimulation drugs or assisted reproductive technology
- Chronic hypertension or renal disease under medical supervision
- Asthma requiring weekly medication
- Diabetes mellitus
- Thyroid disease under medical supervision
- Autoimmune disorder (rheumatoid arthritis, lupus, antiphospholipid antibody syndrome,
scleroderma)
- Hematologic disorders (chronic anemia, sickle cell disease, thrombocytopenia,
coagulation defects, thrombophilia)
- Cancer
- HIV or AIDS
- Epilepsy or seizure on medication or occurrence within 2 years
- Psychiatric disorder (bipolar disorder, depression, anxiety disorder currently
requiring medication)
- Current anorexia nervosa or bulimia
- Previous severe preeclampsia, eclampsia, HELLP syndrome
- Previous gestational diabetes
- Previous stillbirth or neonatal death
- Previous very preterm birth (<34 weeks)
- Previous low birthweight (<2,500g)
- Previous macrosomia (greater than or equal to 4,500 g)
The following criteria apply only to obese women:
- Chronic hypertension or high blood pressure requiring two or more medications
- Diabetes while not pregnant
- Chronic renal disease under medical supervision
- Autoimmune disease (rheumatoid arthritis, lupus, antiphospholipid antibody syndrome,
scleroderma)
- Psychiatric disorder (bipolar disorder, depression, anxiety disorder currently
requiring medication)
- Cancer (currently receiving treatment)
- HIV or AIDS
INCLUSION CRITERIA for the TWIN study:
- Twin, viable pregnancy
- 8^(+0) -13^(+6) weeks of gestation (for larger twin)
- Maternal age 18 - 45 years
- Spontaneous pregnancy or pregnancy from ovulation induction or in vitro fertilization
with known date of transfer
- Pregnancy from egg donor or embryo donor (record if anonymous or known source)
- LMP-date and crown-rump length measurement match within certain number of days
according to a standard scheme (for larger twin)
- Expect to deliver at one of the participating hospitals
EXCLUSION CRITERIA for the TWIN study:
- Fetal reduction (medically induced only)
- Congenital anomalies (structural or chromosomal)
- Either twin with an increased nuchal translucency (>99th percentile for crown-rump
length; i.e. 3.5 mm or more)
- Monochorionic twins
- Crown-rump length discordance >10%
|