The association between women's overall experience of labor and birth and a range
of possible explanatory variables were studied in a group of 1111 women who participated
in a birth center trial. Data were collected by a questionnaire in early pregnancy
(demographic background, parity, personality traits, and expectations), hospital records
(pharmacological pain relief, induction, augmentation of labor, duration of labor,
operative delivery, and infant outcome), and a follow-up questionnaire 2 months after
the birth (the principal outcome "overall experience of labor and birth," pain, anxiety,
freedom in expression, involvement, midwife, and partner support). Logistic regression
was conducted by including all variables that were associated with the birth experience
when analyzed one by one. In a second regression analysis, only explanatory variables
measured independently of the principal outcome were included; that is, only data
collected from the pregnancy questionnaire and the hospital records. The first regression
analysis identified five explanatory variables: involvement in the birth process (perceived
control) and midwife support were associated with a positive experience; anxiety,
pain, and having a first baby with a negative experience. Parity remained a significant
predictor in the second regression analysis, but the others were replaced by augmentation
of labor, cesarean section, instrumental vaginal delivery, and nitrous oxide (Entonox),
which were all associated with a negative birth experience.