Subjects ranged in age from < 2 years old (4 % of sample) to over 60 years (1 % of sample). Overall, 53 % were male, 84 % were Saudis (16 % were expatriates), and 41 % were between 20 and 40 years (the primary reproductive age) (Total N = 1000). However, the 10–20 year olds are either in the reproductive phase, or soon will be. 62 % were in the 10–40 year old age group, of which 47 % were female. Thus, 284 were women of child-bearing age. 4.3 % of the females were pregnant at the time of the survey (3.9 % for Saudis; 6.4 % for Expatriates). Of expatriates, about 79% were from nearby countries (Middle East/North Africa), 13% from Asia, 6% from Africa, and 2% from Europe/North America. While the median residency of Saudi Arabians was 21–25 years, for expatriates it was < 5 years (which relates to total exposure time). The mean Saudi household had 5.4 ± 2.7 members, while the mean expatriate household had 5.2 ± 2.5 members, which as rather similar.