1. Projecting twinning rates through the year 2100;Oleszczuk;J Reprod Med,1999
2. Births;Ventura;Natl Vital Stat Rep,2001
3. Trends in twin and triplet births;Martin;Natl Vital Stat Rep,1999
4. Contribution of assisted reproductive technology and ovulation-inducing drugs to triplet and higher-order multiple births—United States, 1980–1997;Morb Mortal Wkly Rep CDC Surveill Summ,2000
5. Delayed childbearing and the outcome of pregnancy;Berkowitz;N Engl J Med,1990