Risks of pregnancy and birth, birth presentation, and mode of delivery in relation to the age of primiparous women.

OBJECTIVES

The aim of this study was to analyse the age distribution of primiparous women and its influence on pregnancy and birth risks, presentation at birth and mode of delivery.

STUDY DESIGN

We analysed the perinatal statistics of eight German federal states for the years 1998-2000. For our analysis we defined maternal age groups as follows: < 22, 22-32, > 32 years.

RESULTS

We identified a total of 508,926 singleton pregnancies. 247,593 of these were delivered by primiparous women without preceding live or stillbirths. The mean age of the primiparas was 26.9 years. For older primiparas > 32 years the proportion with previous miscarriages and terminations of pregnancy was > 20 %. The risk of premature rupture of membranes, abnormal CTG and prolonged labour increased clearly with age. 91.0 % of women < 22 years and 84.5 % of women > 32 years had a normal cephalic presentation. Regarding the mode of delivery, 77.1 % (< 22 years) and 53.1 % (> 32 years) experienced spontaneous delivery, 14.5 % (< 22 years) and 32.3 % (> 32 years) had a Caesarean section.

CONCLUSIONS

Older primiparas have a higher proportion of previous miscarriages and terminations of pregnancy. They more commonly experience pathological presentations and also more frequently require Caesarean section. This means that a delayed first pregnancy - an increasingly common phenomenon in Germany - goes along with an increased likelihood of birth risks, Caesarean sections and peripartal interventions. Older primiparous women constitute a special risk group which may require a more intense level of care.