Fig. 2

Infant and child mortality rates by groups of educational assortative mating: 2008–2018 Nigeria DHS. (1) Homogamy low –both parents have at most primary school education, (2) Homogamy high –both parents have at least secondary education, (3) Hypergamy –father has at least secondary and the mother has at most primary, (4) Hypogamy – the father has at most primary and the mother has at least secondary