1. Mercer, Inc. Women’s health issues: infertility as a covered benefit;William,1997
2. Use of infertility services in the United States;Wilcox;Obstet Gynecol,1993
3. Reproductive potential in the older woman;Gindoff;Fertil Steril,1986
4. Time required for conception in 1727 planned pregnancies;Tietze;Fertil Steril,1950
5. Fundamental considerations;Keller,1984