Contraceptive compliance with a levonorgestrel triphasic and a norethindrone monophasic oral contraceptive in adolescent patients Elizabeth R. Woods, MD, MPH: Estherann Grace, MD: Kathryn Klein Havens, MD: James L. Merola, PhD,b and S. Jean Emans, MD"

Boston, Massachusetts OBJECTIVE: This study was undertaken to assess the impact of two low·dose oral contraceptive pills on compliance and side effects in adolescent patients. STUDY DESIGN: The use of a levonorgestrel-containing triphasic pill (N = 114) was compared with that of a monophasic (1 + 35) norethindrone-containing pill (N = 110) at two different sociodemographic sites. RESULTS: No significant difference in compliance or pill satisfaction was observed between the pills. Socioeconomic factors were the overriding predictors of compliance. At 3 and 12 months of follow-up, there were significantly fewer compliants of overall side effects (p < 0.001 and p = 0.004, respectively), breakthrough bleeding (p = 0.017 and p = 0.018), and pill amenorrhea (p = 0.002 and p < 0.001) among users of the triphasic pill. Mean weight change at 12 months was + 1.1 kg for the monophasic pill and - 0.1 kg for the triphasic pill. All known pregnancies occurred among noncompliant city clinic patients. CONCLUSIONS: Adolescents experienced fewer side effects with the triphasic pill than with the monophasic one, but compliance was the same. (AM J OBSTET GVNECOl 1992;166:901-7.)

Key words: Contraceptive compliance, adolescents, birth control, oral contraceptive

Adolescent pregnancy continues to be a major problem in the United States, with rates considerably higher than those of other developed countries . '.2 Initiation of contraception continues to be delayed and inconsistenl.'·ll In a previous study in our clinics,' many of the predictors of compliance in adolescents with followup at three different sites (an inner-city adolescent clinic, a birth control clinic in a mid sized industrial city, and a suburban private practice) were sociodemographic factors that are difficult for health care professionals to change. However, the lack of real or perceived side effects was associated with improved compliance. The new triphasic oral contraceptive pills have lower progestin and estrogen content than many commonly prescribed monophasic pills. However, it is unclear if adolescents can follow the more complex packaging of the triphasic pills. This study was undertaken to assess

From the Division of Adolescent/Young Adult Medicine' and Management Information Systems,' Children's Hospital. Supported in part by Syntex Laboratories and Wyeth-Ayerst Laboratories. Presented in part to the Society for Adolescent Medicine, March 1989. Received for publication April 5, 1991; revised August 4,1991; accepted August 27, 1991. Reprint requests: Elizabeth R. Woods, MD, MPH, Division of AdolescentlYoung Adult Medicine, Children's Hospital, Boston, MA

02115. 611 133390

the impact on reported side effects and adolescent compliance with a levonorgestrel-containing triphasic pill compared with our previous study of a norethindronecontaining (1 + 35) monophasic pilP Material and methods Two hundred twenty-four patients who were starting oral contraceptives for birth control for the first time were entered into the study. Patients were recruited from two different sites: a hospital-based city clinic (N = 124) and a suburban adolescent private practice (N = 100) with 114 receiving a levonorgestrel-containing triphasic pill (Triphasil 28d, Wyeth-Ayerst Laboratories, Philadelphia) and 110 receiving a monophasic norethindrone-containing pill (Norinyl 1 + 35, Syntex Laboratories, Palo Alto, Calif.). In compliance with our Human Investigation Committee's guidelines for quality improvement, standard medical care was given and informed consent for initiating oral contraceptive pills was obtained. As in our previous study, which included only patients using a monophasic pill,' data about demographics, sexual history, previous birth con trol use, career goals, concerns about potential side effects, and parental and partner knowledge of the contraceptive pill were collected. A physical examination including height, weight, blood pressure, and pelvic examination was performed. Each patient was provided with a 3month supply of contraceptive pills. Patients were given 901

902

Woods et al.

March 1992 Am J Obstet Gyneco1

%

90

84 68

60

54 30

o

cc

Overall

[1 Levo



pp Nor

Fig. 1. Compliance with levonorgestrel triphasic (Levo) and norethindrone monophasic (Nor) oral contraceptive at 3 months of follow-up. ee, City clinic patients ; PP, private practice patients.

Table I. Demographics of patients receiving levonorgestrel-containing pill compared with norethindrone-containing pill

Site of health care Adolescent clinic Private practice Residence Metropolitan Suburban School Race Black White Insurance Medicaid Other Age (yr, mean ± SD)

L evonorgestrel-containing pill (n = 114)

Norethindrone-containing pill (n = 110)

63 51

61 49

0.98

47 47 20

56 35 19

0.29

36 61

43 72

0.23

21 93 17.4 ± 2.3

26 84 17.0 ± 2.0

0.34

the monophasic pill in the first block of time (December 1983 through June 1984) and the triphasic pill in the subsequent block of time (May 1985 through June 1987). Follow-up information was obtained at the 3-month visit and at the visit closest to 12 months for long-term follow-up. Data at follow-up visits included blood pressure, weight, menstrual pattern, side effects, pregnancy, and compliance with taking the oral contraceptives. Compliance was defined as both returning for the follow-up visit and taking the pill as prescribed or stopping the pill because of no longer needing contraception. Data analysis was performed with the SAS statistical package. l 2 Fisher's exact test (two-tailed) or X2 test was used for all categoric variables. For continuous variables

P Value

0.15

the appropriate t test was performed when comparison groups had equal variances (as assessed by the F-test result), and an approximation of the t test was performed when comparison groups had unequal variances. 13 All results are reported as mean ± SD. SAS's general linear model, stepwise regression, and CATMOD logistic regression subroutines were used to assess the predictor's relative contribution to R2 and the overall significance of the models. Results

The mean age of the 224 patients was 17.2 ± 2.1 years; 21 % received Medicaid; 37% were black and 63% white; 46% resided in the city, 37% in the suburbs, and 17% at school. There were no significant demographic differences between patients started on a regimen of

Compliance with two different contraceptive pills

Volume 166 Number 3

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12 month

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Contraceptive compliance with a levonorgestrel triphasic and a norethindrone monophasic oral contraceptive in adolescent patients.

This study was undertaken to assess the impact of two low-dose oral contraceptive pills on compliance and side effects in adolescent patients...
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