Contraceptive practice and unplanned pregnancy among single university students.

The sexual behaviour and contraceptive practices of a random sample of unmarried university students were compared with those of a group attending the student health service with an unplanned pregnancy. The immediate cause of most pregnancies in this series was incorrect use of a rhythm method. Irregularity of the menstrual cycle may have been a contributing factor in many cases. Psychological factors influencing the desire for pregnancy, while present, were not major contributing causes in many pregnancies.