What happens to a country when its young people stop having sex? Japan is finding out Abigail Haworth investigates. 7–8 Children 6–7 Children 5–6 Children 4–5 Children 3–4 Children 2–3 Children 1–2 Children 0–1 Children Mother and child, in Bhutan The total fertility rate (TFR) - the average number of children born to a woman over her lifetime — differs significantly between different regions of the world. In , the highest estimated TFR. Rear entry sexual positions described and explained, with high quality sex positions pictures.