No association between term birth gestational age and academic achievement in children: JAMA

Based on the study of more than 500 000 children, the researchers revealed no difference in school achievement between children born at 39 versus 40 weeks and no evidence of better test scores between children born at 41 weeks versus 40 weeks. Scores were generally lower for children born at 37 to 38 weeks versus 40 weeks.

"These new insights about differences in school achievement when weighing short-term and long-term benefits and risks can be relevant for those making decisions about delivery timing at term," George L. Wehby, University of Iowa, Iowa City, wrote in his study.

Children born preterm are known to have a higher risk of perinatal complications and poorer developmental outcomes, including lower academic achievement during childhood. However, the association between gestational age and subsequent developmental outcomes (such as academic achievement and cognition) is complex for children born at term.

During the period 37 to 41 gestation weeks, 37 to 38 weeks is considered early term, 30 to 40 weeks is considered full term, and 41 weeks are considered late term. Within this range, neonatal outcomes are generally worse at 37 to 38 weeks, and 39 to 40 weeks is considered optimal for minimizing perinatal complications.

The study was conducted to examine differences in academic achievement among children born between 37 and 41 weeks gestational age.

The study linked birth certificates of children born in Iowa from 1989 to 2009 with their school test scores for grades 2 to 11 from 2017 to 2018. Statistical analysis was performed from January to March 2023.

The academic performance of children born at gestational age at 37, 38, 39, and 41 weeks was compared with children born at 40 weeks from clinical or obstetric and calendar measures.

The study outcome was scores achieved in national percentile rankings (NPRs) on standardized school tests in reading and math.

The study led to the following findings:

• The sample included 536 996 children (50.7% male children and 49.3% female children) with math scores (3 576 045 child-grade observations; 6.6%, 15.7%, 28.6%, 35.5%, and 13.7% born at 37, 38, 39, 40, and 41 weeks, respectively) and 537 078 children with reading scores (3 590 408 child-grade observations).
• Score differences for those born at 39 vs 40 weeks were −0.028 NPRs for math and 0.085 NPRs for reading using the clinical or obstetric measure and 0.03 NPRs for math and 0.13 NPRs for reading using the calendar measure. With the clinical or obstetric measure, score differences between those born at 41 and 40 weeks were 0.19 NPRs for math and 0.098 NPRs for reading.
• With the calendar measure, score differences for those born at 41 weeks were −0.22 NPRs for math and −0.28 NPRs for reading.
• With the clinical or obstetric measure, score differences between those born at 37 and 38 weeks versus 40 weeks were −0.59 NPRs and −0.44 NPRs, for math, and −0.066 NPRs and −0.19 NPRs, respectively, for reading.

The study indicates no evidence of a difference in reading and math scores over grades 2 to 11 among children born between 39 and 40 weeks gestation, and no overall evidence of better scores among those born at 41 weeks’ gestation versus 40 weeks’ gestation.

The study stated, "The results can further inform decisions on delivery timing at term birth by offering insights into long-term associations of delivery timing with school achievement and cognitive development."

Reference:

Wehby GL. Association Between Gestational Age and Academic Achievement of Children Born at Term. JAMA Netw Open. 2023;6(7):e2326451. doi:10.1001/jamanetworkopen.2023.26451