Data collection
Standard operating procedures were elicited to all research
personnel in the launching meeting before the formal study. The
usage of standardized data collection instruments were explained
in detail.
After obtaining informed consent, we asked the women to
participate in a 20-minute personal interview in which trained
research personnel used a standardized structured questionnaire to
elicit information regarding maternal sociodemography, sex
activity during pregnancy and medical history. Prenatal and
delivery medical records were reviewed by trained research nurses