Women who are given a one-year supply of oral contraceptives are less likely to become pregnant in the subsequent year than are women who receive a one- or three-month supply.1 In addition, among women who received oral contraceptives through California’s family planning program, those given a one-year supply were more likely to still be using the method 15 months later than were those given one- and three-month supplies. Results of multivariate analyses showed that the odds of receiving a one-year supply varied by age, parity, and race and ethnicity: Women younger than 20 and Latinas were less likely than others to be given a year’s supply; women with one or no children and Asian women were more likely to receive it.

For the 84,401 women who received oral contraceptives through California’s family planning program in January 2006, researchers linked data on the number of pill packs dispensed with pregnancy events (births, abortions, miscarriages or ectopic pregnancies) that occurred between January 2006 and January 2007, as reported in California’s Medicaid eligibility data system and statewide births file. Demographic data were obtained from the family planning program’s client enrollment records. Chi-square testing was used to examine differences in method continuation, method switching, and pregnancy and abortion rates by number of contraceptive packs received. Multivariable logistic regression models that controlled for factors that may affect pregnancy rate were run to examine the relationship between the number of pill packs dispensed and subsequent pregnancies and abortions.

Overall, 58% of women received three packs of oral contraceptives; 20% received one pack, 11% received 12 or 13 packs (a one-year supply) and 11% received some other number. One-year supplies were given most often to women younger than age 20 and least often to women older than 40; 18% of women younger than 20 received 12 or 13 packs, compared with 4% of those older than 40. Spanish-speaking Latinas were the least likely to receive a one-year supply of oral contraceptives (3%), and Asian and white women were the most likely to (20% and 19%, respectively). Compared with women who had children, women with no children were more likely to receive the one-year supply (17% vs. 3–6%). Reflecting that dispensing laws prohibit pharmacies from distributing more than a 100-day supply, no women who got oral contraceptives from pharmacies received 12 or 13 packs; 24% received one pack, 74% received three packs and 3% received some other number. Among those obtaining oral contraceptives from clinics, 11% received one pack, 27% received three, 34% received 12 or 13, and 28% received some other number.

Women younger than 20 disproportionally seek care at clinics that are able to dispense one-year supplies of oral contraceptives; for this reason, they were more likely than others to receive a one-year supply. However, within those clinics, women younger than 20 were less likely than women older than 40 to receive a one-year supply (odds ratio, 0.8); women in their 20s and those in their 30s were more likely than women aged 40 or older to receive a one-year supply (1.2 for each). Within California’s family planning program as a whole and within clinics that can dispense one-year supplies, both English- and Spanish-speaking Latinas had lower odds than whites of receiving 12 or 13 pill packs (0.2–0.9), while Asian women had elevated odds of receiving a year’s supply (1.1–1.2). Overall, black women were less likely than whites to receive a one-year supply (0.7), but this association did not hold in clinics able to dispense one-year supplies. Throughout the family planning program, women with one child or no children were more likely than women with two or more children to receive a one-year supply of contraceptive pills (1.4–2.4). Compared with previous clients who were new to oral contraceptives, new family planning clients were more likely to receive a one-year supply (1.5–1.8), while clients who had received the pill in 2005 were less likely to receive a one-year supply (0.4–0.7).

Recipients of one-year supplies of oral contraceptives were more likely to still be using that method at 15 months than recipients of one- and three-month supplies (40% vs. 21% and 25%). They also were less likely to switch methods—only 7% did so, compared with 11% of those who received one pack and 10% of those receiving three. Although 2.8% of all women who received oral contraceptives in January 2006 became pregnant in the subsequent year, the proportion was significantly lower among women receiving a one-year supply than among those receiving one- and three-month supplies (1.2% vs. 2.9% and 3.3%). Overall, the rate of abortion was 0.53%; as with pregnancy, the proportion was lower among those who received a year’s supply of oral contraceptives (0.18%) than among those who received one- or three-month supplies (0.52% and 0.63%, respectively).

The odds of becoming pregnant in the year following their family planning visit were lower among those who received a year’s supply of oral contraceptives than among those who received a one-month supply (odds ratio, 0.7), and were lower among new family planning program clients than among established clients who were new pill users (0.6). The odds of becoming pregnant were higher for Asians (1.6), blacks (1.9) and Latinas (2.5–4.7) than for white women. A similar pattern emerged in regard to abortion: Those who received a one-year supply of oral contraceptives and new clients had significantly reduced odds of having an abortion (0.5 and 0.6, respectively); the odds of having an abortion were elevated for Asians (2.1), blacks (2.2) and Latinas (2.6–4.4).

The researchers acknowledge that their results may be affected by the fact that providers likely dispensed greater numbers of packs to women who were more compliant users. Also, the findings apply only to pregnancies and pregnancy outcomes covered by Medicaid. Despite these limitations, the researchers believe that making oral contraceptives more accessible may reduce unintended pregnancy and abortion rates: They estimate that if the women who received one- and three-month supplies of oral contraceptives in January 2006 had the same pregnancy and abortion rates as those who received one-year supplies, 1,300 publicly funded pregnancies and 300 such abortions would have been prevented. The researchers suggest that health insurance and public health programs increase dispensing limits on oral contraceptives to a one-year supply.—L. Melhado