Material and Method: A retrospective cohort study was conducted to investigate 957 singleton pregnant women attending labor rooms in Naresuan University Hospital between October 2006 and September 2013 by comparing the pregnancy outcomes of 268 teenage pregnancy (woman age less than 20 years at the first time of antenatal care visit) with 689 non-teenage pregnancy (woman age 20 to 34 years). The obstetrics and neonatal complication was the main outcome of interest.

Results: The incidence of teenage pregnancy was 15.24% during seven years of study. As opposed to non-teenage mothers, complete attending antenatal care visit was less likely to be found among teenage mothers, 66.5% vs. 90.5% respectively (p<0.001). Higher proportion of normal vaginal delivery was found in teenage mothers (59.7% vs. 36.4%). The occurrence of cephalo-pelvic disproportion (CPD) seemed to be lower in teenage group as compared to non-teenage group, 14.5% vs. 26.4% (p<0.001). In addition, postpartum hemorrhage was unlikely to occur in teenage group, 3.8% vs. 8.4% (p = 0.016). The proportion of preterm birth was found to be higher in teenage pregnancy compared to non-teenage pregnancy (16.2% vs. 5.5%, p<0.001). At birth, the higher proportion of infants who had low Apgar scores (<7) at 1-minute was found in teenage pregnancy, 7.1% vs. 3.1% (p = 0.01).

Conclusion: Even though obstetric complications were less likely to occur among teenage pregnancies, most of the neonatal untoward consequences were observed in mothers with younger ages. The finding suggests the need of appropriate health care services for teenage mothers as to monitor harmful complications to both mother and her child.

Keywords: Teenage pregnancy, Obstetric outcome, Neonatal outcome