The most common birth problem associated with maternal cigarette smoking is O low birth weight. O poorly developed lungs and a risk for asthma later in life. O brain damage and mental retardation. O head and facial deformities.

________ Although the incidence of neural tube defects in the United States declined post-folic acid fortification, some women are still at risk. Which of the following options represents a risk group for inadequate folate status and a neural tube defect affected pregnancy? a. Non-Hispanic Black women b. Non-Hispanic White women c. Asian Americans d. Hispanic Americans

Birth Defects and Multiple Births A woman who carries multiple offspring at the same time increases the risk of some birth defects. FIGURE 42.18 shows the results of Yiwei Tang's study of birth defects reported in Florida from 1W6 to 2000. Tang compared the incidence of various defects among single and multiple births. She calculated the relative risk for each type of defect based on type of birth, and corrected for other differences that might increase risk such as maternal age, income, race, and medical care during pregnancy. A relative risk of less than 1 means that multiple births pose less risk of that defect occurring. A relative risk greater than 1 means multiples are more likely to have a defect. FIGURE 42.18 Prevalence, per 10,000 live births, of various types of birth defects among multiple aria single births. Relative risk for each defect is given after researches adjusted for the motor's age, race, previous adverse pregnancy experience, education, Medicaid participation during pregnancy, as well as the infant's sex and number of siblings. 4. Does a multiple pregnancy increase the relative risk of chromosomal defects in offspring?