Table 2.

Number of children and clusters and their estimated annual ambient in utero and post-delivery lifetime ${\mathrm{PM}}_{2.5}$ exposure by child birth year for children in the Demographic and Health Survey [DHS, also known as the National Family Health Survey 2015–2016 (NFHS-4)] in India.

	2010	2011	2012	2013	2014	2015	2016	All years
Children/cluster ($n$)
Children	15,206	40,727	51,960	50,769	51,668	33,951	8,507	252,788
Clustera	8,445	19,766	22,548	22,353	22,419	17,217	5,590	27,835
In utero ${\mathrm{PM}}_{2.5}$ exposure (${\mathrm{\mu }\mathrm{g}/\mathrm{m}}^3$)b
Mean (SD)	72.5 (31.7)	68.3 (27.0)	72.3 (28.4)	72.1 (29.1)	71.2 (28.0)	70.8 (26.3)	72.0 (27.8)	71.1 (28.2)
Min	21.2	20.9	22.6	22.4	23.1	24.7	23.7	20.9
Q1	45.7	47.9	51.1	49.9	49.7	50.6	50.2	49.7
Median	61.3	60.1	63.6	63.2	62.4	62.5	62.0	62.4
Q3	96.2	86.9	91.8	91.1	90.4	88.2	95.6	90.3
Max	145.1	142.1	153.5	153.0	144.1	144.2	141.4	153.5
Post-delivery lifetime ${\mathrm{PM}}_{2.5}$ exposure (${\mathrm{\mu }\mathrm{g}/\mathrm{m}}^3$)c
Mean (SD)	73.7 (30.7)	73.0 (28.9)	72.7 (28.3)	73.1 (28.8)	76.0 (31.7)	75.2 (31.3)	67.9 (28.5)	73.7 (29.8)
Min	15.7	14.4	14.0	14.7	15.6	15.1	17.4	14.0
Q1	48.2	50.5	50.5	50.5	51.0	52.6	48.6	50.6
Median	61.5	63.0	62.8	63.3	65.1	67.2	61.6	64.0
Q3	106.4	101.5	98.8	98.5	101.3	90.9	81.6	98.3
Max	211.2	238.3	247.3	234.6	241.8	232.2	228.6	247.3

Note: Max, maximum; min, minimum; ${\mathrm{PM}}_{2.5}$, particulate matter $\le 2.5\mathrm{\mu }\mathrm{m}$ in aerodynamic diameter (fine particulate matter); Q, quartile; SD, standard deviation.

^a Cluster is a primary sampling unit (PSU) or a segment of PSU, of around 100–150 households, in the two-stage clustering sampling design of the DHS/NFHS-4.

^b 9-month average of ambient ${\mathrm{PM}}_{2.5}$ exposure prior to child birth month.

^c Average of post-delivery lifetime ambient ${\mathrm{PM}}_{2.5}$ exposure from month of child birth until the month of death, or month of DHS/NFHS-4 interview of the child’s mother (censoring).