Manipulation of Birth Timing and its Impact on Health at Birth

Manipulation of Birth Timing and its Impact on Health at Birth

Jie Peng

November 29, 2015

Abstract

Scheduling births without any medical reasons by induction and caesarean section has become more and more common all over the world. This research assesses the impact of small change of birth timing on infant health at birth, by exploiting a phenomenon that some parents avoid holiday babies, especially in holiday season at the end of the year. I focus on all full term singleton birth delivered by mothers without medical problems on this pregnancy, because newborns health outcomes are believed to be similar in the traditional full term pregnant period (37 0/7 weeks to 41 6/7 weeks). Using New Jersey birth certificate data with baby’s exact date of birth and exact date of mother’s last menstrual period (LMP) during the years 1989 to 2011, it was estimated that about 210 singleton births per year are moved to an early time from Christmas break and New Year’s break in holiday season at the end of the year. This difference of birth number in breaks (Christmas break and New Year’s break) and in other days of holiday season at the end of the year is mainly driven by moving the caesarean section and induction procedures to early time. I find the group of parents whose babies were born shortly before holiday break appear to be slightly older, more educated, more likely to be white, be married, pay more prenatal visits, and have less risk behavior during this pregnancy than parents of those born in holiday break. I also find that the group of babies with small change of birth timing have a shorter gestation age, a lower birth weight, a lower Apgar score, a lower likelihood of getting normal Apgar score, and a higher probability of mechanical ventilation usage.

JEL classification: I12, I19

Keywords: elective induction, elective caesarean section, holiday season, manipulation of birth time, health outcomes