This retrospective study reports on the course of pregnancy and delivery in 12- to 14-year old girls during a period of 8 years. At the time of delivery 44 mothers (0.3%) out of 13,178 had not finished their 15th year; this adolescent primiparae were compared to a group of equal size including primiparae between 20 and 30 years of age. Whereas other studies report a higher risk of several pregnancy-related complications, our investigation mainly found a higher percentage of premature deliveries (13.6%). A significantly shorter duration of pregnancy resulted in lower birth weights in the adolescent group. Furthermore we noted a higher frequency of pyelitis gravidarum in this group. Operative delivery had to be performed in 9.1% of the cases (3 X cesarean sections, 1 X forceps), compared to 13.6% in the control group (3 X cesarean sections, 3 X forceps). In the adolescent group no other obstetric complications occurred; whereas a higher incidence of puerperal infections (endometritis) was noted. 26 adolescent mothers were foreigners of southern European descendence; in only 8 cases the putative father was notified; a third of the young mothers decided to enter their child in the state adoption program.