PIP: The aim of this study was to describe the variation in marital fertility in Warri-Effurun in Nigeria and to describe an approach to population education and family planning suitable to the fertility patterns. The sample included 662 households of monogamously married women aged 15-49 years in 21 neighborhoods in Warri Effurun conurbation in Bendel State, a very fast growing urban center. Couples had to be in their first marriages and to have resided in the area for at least six months. Between 1963 and 1989, population increased from 55,254 to 117,442, a rate of 2.9%. Marital fertility was taken as the number of surviving children from approved legal sexual unions. The highest mean number of surviving children was 3.519 among those who first married between the ages of 15 and 19 years. 9.3% of women with seven or more children were married between the ages of 15 and 19 years. Women aged 40-49 years had the highest mean number of surviving children (5.3) and the largest number of pregnancies and live births. There were 10 neighborhoods that had higher average marriage ages and 10 neighborhoods with lower marriage ages. Neighborhoods with higher marriage ages had more migrants and were more elitist. Lower marriage age neighborhoods had more indigenous people with early marriages and early childbearing. The highest fertility was found in Midwest College, Nigerian Port Authority, Okumagba Layout, and Senior Staff Quarters, with later marriage and childbearing and a better educated population. The highest mean age of marriage was 28.45 years in the Nelson Obahor neighborhood, which also recorded 2.68 births and 2.65 surviving children, which was the lowest in the city. The lowest mean age of marriage was 20.04 in Pessu, which had 3.04 as the mean number of births, followed by 20.18 in Ogunnu, which had 4.64 births. The highest mean number of surviving children was 4.47 in Ajamogha and 4.0 in Senior staff quarters. The correlation between mean age of marriage and mean number of surviving children was very high. The recommendation was to plan population education and family planning services in neighborhoods with high fertility.