Delaying the first childbirth to an advanced age has increased significantly during the last decades, but little is known about older first time mothers' experience of childbirth. This study investigates the associations between advanced maternal age in primiparous women and the postnatal assessment of childbirth.The study was based on the National Norwegian Mother and Child Cohort Study (MoBa) conducted by the Norwegian Institute of Public Health. Data on 30 065 nulliparous women recruited in the second trimester 1999-2008 were used. Three questionnaires were completed: around gestational week 17 and 30, and at 6 months postpartum. Medical data were retrieved from the national Medical Birth Register. Advanced age was defined as ≥32 years and the reference group as 25-31 years. Descriptive and multiple logistic regression analyses were conducted.Primiparous women aged 32 years and above expressed more worry about the upcoming birth than the younger women (adjusted OR 1.13; 95% CI 1.06-1.21), and 6 months after the birth they had a slightly higher risk of having experienced childbirth as 'worse than expected' (adjusted OR 1.09; 95% CI 1.02-1.16). The difference in birth experience was explained by mode of delivery. Comparisons within subgroups defined by the same mode of delivery showed that the risk of a more negative birth experience in the older women only applied to those with a spontaneous vaginal birth (adjusted OR 1.12; 95% CI 1.02-1.22). In women delivered by cesarean section, the older more often than younger women rated childbirth as 'better than expected' (elective cesarean delivery: adjusted OR 1.36; 95% CI 1.01-1.85, emergency cesarean delivery: adjusted OR 1.38; 95% CI 1.03-1.84).Postponing childbirth to ≥32 years of age only marginally affected the experience of childbirth. Older women seemed to manage better than younger with having an operative delivery.