Effects of short birth spacing on birth-order differences in child stunting: Evidence from India
Sunaina Dhingra and Prabhu L. Pingali; PNAS February 23, 2021 118 (8) e2017834118
(126).png)
Figure: Child height by birth order. The bars represent the mean HAZ for Indian children.
The question of whether firstborn children have a height advantage over later-born children is important, given the persistently poor height outcomes in developing countries. Using data on young Indian children, we show that later-born children lag behind firstborns in stunting outcomes. This is only true, though, if higher birth-order children were born within 3 y of the birth of their elder siblings. No difference in height-for-age is observed for children born with spacing of 3 or more years. India’s family planning interventions have largely focused on reducing the total fertility rate with less attention given to length of birth spacing between children. A stronger focus on increasing the time interval between births could prevent adverse stunting outcomes for surviving children. Do firstborn children have a height advantage? Empirical findings have found mostly that, yes, second or higher-order children often lag behind firstborns in height outcomes, especially in developing countries. However, empirical investigations of birth-order effects on child height overlook the potential impact that birth spacing can have. We provide an explanation for the negative birth-order effect on stunting outcomes for young Indian children and show it is driven by short preceding-birth spacing. We find that firstborn children are taller than children of higher birth order: The height-for-age gap for third (or higher)-order children is twice the gap for children second in birth order. However, this pattern is observed when spacing between later-born children and their immediate elder siblings is fewer than 3 y. Interestingly, the firstborn height advantage disappears when later-born children are born at least 3 y after their elder siblings. Thus, our findings indicate that spacing length between children explains differences in height, over birth order. Although India’s family planning policy has resulted in a substantial reduction in total fertility, its achievement in spacing subsequent births has been less impressive. In showing that spacing can alleviate or aggravate birth-order effects on attained height, our study fills an evidence gap: Reducing fertility alone may not be sufficient in overcoming negative birth-order effects. To reduce the detrimental effects of birth order on child stunting, policy responses—and therefore research priorities—require a stronger focus on increasing the time period between births.
Views: 270