University of Texas at Austin Population Research Center
Population Research Center, UT-Austin • UT-El Paso • Ibis Reproductive Health


Prospective Study

In El Paso, Texas, we recruited 514 oral contraceptive pills (OCP) users who obtained pills over the counter from a Mexican pharmacy and 532 who obtained OCPs from a family planning clinic in El Paso.  A baseline interview was followed by three consecutive surveys over nine months. Data were collected from December 2006 through February 2008. The face-to-face baseline interview covered information on the participant’s background, social networks, and bi-national relations; motivation for choosing their pill source; medical, birth, and contraceptive histories; pill-use knowledge and practice; and childbearing intentions.  The second and third follow-up interviews took place approximately three and six months after the initial interview, and were administered via telephone.  During the 20 minute telephone interviews, women were asked about changes in their health and pill-use practice during the prior three months, as well as follow-up questions on contraceptive knowledge.  The final (time 4) interview was completed nine months after the baseline interview, also in person and lasted about one hour.  We asked participants about previous hypertension diagnoses and current risks, postpartum contraception and barriers to contraceptive use, and included open-ended questions soliciting women’s beliefs about how the pill works and its side effects.  In addition, we measured participants’ height, weight and blood pressure to create objective measures of potential contraindications to OC use.

Of the 1,046 Baseline interviews, 965 completed the Time 2 interview, 936 the Time 3 interview and 941 the Time 4 interview.  Our final retention rate was 90%.  The majority of 105 participants who could not be contacted had moved away from the El Paso area (n=68).  The rest (n=37) declined further participation.   

Five datasets from the BCAS Prospective Study, along with the corresponding codebooks and questionnaires, are available through DSDR: Data Sharing for Demographic Research.