Estimation of couple fecundity in the general population and the association with monthly time-varying ambient particulate matter exposure in low- and middle-income countries: A population-based multi-center epidemiological study

Declining total fertility rates have been observed in low- and middle-income countries (LMICs). However, it remains unclear if this trend is related to a reduction in fecundity of general population. Research evidence on contributing factors to fecundity reduction is also limited. We aimed to first estimate couple fecundity in LMICs and then investigate its association with ambient particulate matter (PM) exposure.