Notes
Use of contraception prior to the calendar indicates whether the respondent: 1) was using a method in the first month of the calendar; 2) was not using in the first month of the calendar, but used in the interval prior to the calendar, 3) was not using in the first month of the calendar and had not used in the interval prior to the calendar, but had used in an earlier interval, 4) had only used since the start of the calendar, 5) had never used.
Variables V385 to V392 refer to the use/nonuse of contraception in the interval between the last birth prior to the start of the calendar and the start of the calendar.