A survey of under-18 year old and 20-29 year old primigravidae delivered at the Port Moresby General Hospital: a comparative study of their sociodemographic and sexuality characteristics and contraceptive knowledge and experience.

From July 1992 to August 1993, 330 under-18 year old primigravidae (cases) and 330 randomly selected 20-29 year old primigravidae (controls) who were delivered at the Port Moresby General Hospital were sequentially studied, using a standardized, pretested, precoded questionnaire. In stepwise logistic regression analysis, significantly more of the cases had menarche at less than 15 years of age, learned before menarche that sex causes pregnancy, were of highland origin, were unemployed, or had partners who were unemployed; significantly fewer of the cases thought that one sexual act could cause pregnancy, had knowledge of or had ever used a family planning method, or had planned this pregnancy.