• Perinatal mortality, i.e., the number of stillbirths (fetal deaths of 28 weeks or more of gestation) and the number of deaths within the first 0-6 days of life per 1000 births (live births and stillbirths) [ Time Frame: 3.5 years from beginning of enrollment ]
  
• Gastrointestinal side effects at monthly visits [ Time Frame: delivery of last infant in the study, 3.5 years ]
  

• Maternal anemia between 24 and 28 weeks gestation
  
• Maternal anemia at 4-8 weeks postpartum
  
• Infant gestational age at birth, preterm delivery
  
• Infant birth weight, low birth weight
  
• Infant low weight-for-height at ages 6 and 12 months
  
• Infant low weight-for-age at ages 6 and 12 months
  
• Infant low height-for-age at ages 6 and 12 months
  
• Infant anemia at ages 6 and 12 months
  

In the project area in China, the rate of perinatal mortality (stillbirths and infant deaths within 6 days of birth) is two times that of the United States. Causes of perinatal mortality include, but are not limited to, low birth weight and preterm delivery. Anemia (low hemoglobin) among pregnant women is associated with low birth weight and preterm delivery and also is elevated in the project area. Supplements of iron, folic acid, and other vitamins and minerals can prevent anemia among pregnant women, but the effects of these supplements on other maternal and infant health outcomes are unclear.

Since 1993, the People's Republic of China has recommended that newly married women, and those who plan pregnancy, take 400μg of folic acid daily through the first trimester of pregnancy. Although WHO recommends that pregnant women take iron and folic acid supplements, there is currently no national recommendation that pregnant women in China take iron or other vitamin or mineral supplements (other than folic acid). UNICEF is now testing a prenatal vitamin and mineral supplement in programs to prevent low birth weight. Our study will provide additional information about the health impact of the UNICEF prenatal supplement versus an iron and folic acid supplement versus folic acid alone.

Comparisons:

• Infants of women who receive daily prenatal supplements that contain 400μg folic acid alone, will be compared with infants of women who receive daily supplements that contain 30 mg iron and 400 μg folic acid.
• Infants of women who receive daily supplements that contain 30 mg iron and 400 μg folic acid will be compared with infants of women who receive a daily supplement containing 30 mg iron, 400μg folic acid and other vitamins and minerals (UNICEF formulation).