Age at end of hormone replacement medication use is based on self-report. Female participants are first asked if they have ever taken medication for hormone replacement. Those who respond "yes" are asked to report the form of medication (e.g., pill, patch), age at first use, and current medication use. Participants who respond "no" to current usage are then asked to report their age at the time of last use:

1. Did you ever take any type of estrogen hormonal medication, for example Premarin Ogen, or Estrace, or progesterone hormonal medication, for example Provera?
2. Were these estrogen or progesterone hormones in the form of a pill, injection, vaginal cream or suppository, or skin patch?
3. How old were you when you first took this/these medications?
4. Are you currently taking this/these medication(s)?
5. How old were you when you last took this/these medication(s)?

Note: If the response for either age at end of hormone replacement usage or age of first use is not valid, both values are set as missing.