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Method Discontinuation & Pregnancy Among Young Women Who Initiate
Hormonal Contraceptives
Tina Raine-Bennett MD, MPHProfessor
Obstetrics Gynecology and Reproductive SciencesSan Francisco General Hospital
Bixby Center for Global Reproductive Health University of California, San Francisco
October 2010
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
Disclosures
• Speaker Bureau - Merck (Schering Plough) Implanon trainer
• Consultant and Research Grant support on Emergency contraception - Teva (Duramed – Barr)
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
Acknowledgements• Beth Brown MA, MPA• Phil Darney MD, MSc• Anne Foster-Rosales MD, MPH• Cynthia Harper PhD• Abby Sokoloff MPH• Ushma Upadhyay PhD, MPH• RAs: Laura Mendoza, Claudia Paredes, Gloria Roman,
This study was supported by National Institute of Child Health and Human Development Grant R01 HD045480
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
Background• The rate of unintended pregnancy
remains unacceptably high.• Unintended pregnancies have
significant consequences.• They are becoming increasingly
concentrated among minority and socioeconomically disadvantaged women.
Finer et al. Disparities in rates of unintended pregnancy in the U.S., 1994 and 2001 Perspectives , 2006 38:90-96
Unintended Pregnancy Occurs More Frequently in Young, Poor, and Minority Women
0 20 40 60 80 100 120
Race/ethnicity
% of Poverty
Education
Unintended Pegnancies per 1,000 women aged 15-44
< HS DiplomaHS Diploma/GED
Some CollegeCollege Graduate
<100%
100-199%>200%
BlackHispanic
White
Finer et al. Disparities in rates of unintended pregnancy in the U.S., 1994 and 2001 Perspectives , 2006 38:90-96
Women at risk of pregnancy
11%
89%
Not using contraceptivesUsing contraceptives
Contraceptive Use Month of Conception
52%48%
Not using contraceptivesUsing contraceptives
Contraceptive Use PredictsUnintended Pregnancy
Finer et al. Disparities in rates of unintended pregnancy in the U.S., 1994 and 2001 Perspectives , 2006 38:90-96
Method Choice is Key
Improved Delivery systems:• Convenience• Compliance• Efficacy
Vaginal Ring & Contraceptive Patch
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
• By Race– African American less likely to use the pill – African American and Hispanic women more likely to use
injectable– African American women more likely to use condoms
• By Income– Women with Medicaid less likely to use the pill than
women with private insurance
• By education– Less educated women less likely to use the pill and more
likely to use injectable
Contraceptive Method Choice Differences
Frost et al. Factors associated with contraceptive choice and Inconsistent Method Use, United States 2004 Perspectives 2008 40:94-104
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
Significance
• Little is known about use of relatively newer methods
• Our understanding of disparities in contraceptive use by race and socioeconomic status is limited
• Information is needed to help providers understand more about diverse women who present to clinics for birth control
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
Longitudinal Cohort Study
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
Study Objectives• Assess long-term (12 month) use of hormonal
contraception among a diverse cohort of young women
• Assess unintended pregnancy rates and correlation with use patterns
• Compare discontinuation rates of relatively newer methods - the Patch and the Ring to the Pill
• Compare discontinuation rates of Depo-Provera to the Pill
• Assess factors associated with discontinuation
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
Study Setting• Four Planned Parenthood Clinics in Northern CA
•Oakland Eastmont Mall•Hayward•Richmond – Hilltop Mall•Vallejo
• Sub-urban communities• Primarily uninsured; eligible for CA state family
planning assistance program (FamilyPACT)
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
Eligibility Criteria• Age 15-24
• English or Spanish speaking
• Non-married
• Not pregnant or desiring pregnancy in the next year
• Selected to initiate the pill, patch, ring, or DMPA*
• Previous hormonal method use okay but not the method they were currently selecting (also eligible if switching to a new method)
* Enrollment started September 2005; DMPA added to the protocol in October 2005
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
Study Methods• Longitudinal Cohort Study – September 2005 to July 2008• Patient seen by clinic staff using standard clinic protocols
BC method selected• Enrolled in study by research staff - baseline questionnaire
completed• Follow-up questionnaires:
– 3 months– 6 months– 12 months
• Pregnancy tests done at 6- and 12- month follow-ups; chart review at the end of study
• Participants received $30 at baseline, $20 at 3 months and 6 months, and $30 at 12 months
(in-person or by phone)
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
Study Methods
• Outcomes of interest:– Discontinuation of method selected– Subsequent use of hormonal
methods•Switching•Breaks
– Pregnancy
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
Data Analysis
• Kaplan-Meier survival analysis estimates of the probability of continuation
– (women censored if lost to F/U or became pregnant)
• Predictors of discontinuation of selected method – Cox proportional hazards regression model
• Choice of model variables guided by the theory of reasoned action
Understanding and Modifying Contraceptive Behavior
Belief of Consequences &
Value of Consequences
General Attitude Toward
Behavior
Perception of Wishes of
Partners Parents & Peers
Social Expectations
Intent to Engage
in Behavior
Performance of Behavior
Theory of Reasoned Action
Ajzen I, Fishbein M. Understanding attitudes and predicting social behavior. 1980.
Moore PJ, Adler NE, Kegeles SM. Adolescents and the contraceptive pill: the impact of beliefs on intentions and use. Obstet Gynecol. 1996;88:48S-56S.
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
RESULTS
Study Enrollment and Follow-up
Screened 1,501
Women Enrolled: -Pill -Patch -Ring -DMPA
1,387 432 401 259 295
Completed F/U#1 1,238 (89%)
Completed F/U#2 1,257 (91%)
Completed F/U#3 1,208 (87%)
Completed at least one F/U 1,316 (95%)
Baseline Demographics(Comparisons to Pill Initiators)
Pill Patch Ring DMPA Total
Column Percents (N=1,387)
Mean Age 18.6 19.2* 20.4* 18.9 19.2
Race White Latina Black Asian/PI Multi/Other
1224301420
7*28
41*10
14*
1226351214
1428
38*6*
14*
1126361116
Low Neighborhood Income 41 51* 47 40 45
Working or In School 85 82 82 80 82
Defined as living in a zip code where the percentage of families living below the federal poverty level is greater than the national average*P< 0.05 compared to Pill
BaselineContraceptive & Reproductive Characteristics
(Comparisons to Pill Initiators)Pill Patch Ring DMPA Total
Column Percents (N=1,387)
Ever Pregnant 33 52* 60* 59* 49
Ever had a Birth 13 21* 24* 24* 20
Ever had an Abortion 27 44* 50* 50* 41
Ever Used Hormonal BC 29 43* 79* 53* 48
Has Current Main Partner 86 81 85 82 83
*P< 0.05 compared to Pill
BaselineContraceptive Beliefs & Attitudes
(Comparisons to Pill Initiators)
Pill Patch Ring DMPA Total
Column Percents (N=1,387)
Endorsed Negative Attributes of CHC
44 55* 51 65* 53
Peers Very Much Against Use of BC 12 14 18* 10 13
Main Partner Very Much Against Use of BC 15 13 16 10 14
Strongly Agree- Parents Upset if Knew Used BC 25 22 14* 16* 20
*P< 0.05 compared to Pill
Negative Attributes Scale – Level of Agreement with 13 Statements like “It is dirty to put the ring in the vagina” and “it is hard to take a pill every day” and “the patch is messy on the skin”
CHC – Combined Hormonal Contraceptive BC - Hormonal Birth Control
BaselinePregnancy and Contraceptive Use Intentions
(Comparisons to Pill Initiators)
Pill Patch Ring DMPA Total
Column Percents (N=1,316)
Would be very upset if pregnant in next 3 months
45 40 45 45 44
Does not want child in next 2 years or ever
72 72 70 68 71
Very sure will continue BC method selected for 1 year
48 37* 34* 48 42
*P< 0.05 compared to Pill
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
Main Outcomes
Kaplan- Meier Survival Analysis of Continuation of the Method Selected
N= 1,316 (women with at least one F/U visit)
0.00
0.25
0.50
1.00
0 1 2 3 4 5 6 7 8 9 10 11 12
Pill
Duration of use (months)Patch
0.75
Ring DMPA
Prob
abili
ty o
f Co
ntinu
ation
Baseline Factors Associated with DiscontinuationCharacteristic N=1,267 Adjusted Hazard Ratio 95% CI
Method selected Pill Patch Ring DMPA
ref 1.90***
1.18 1.24*
--(1.59 - 2.27)(0.94 - 1.46) (1.03 - 1.51)
Older Age, years 0.96*** (0.93 - 0.99)
Race White Latina Black Asian/PI Multi-racial/Other
ref 1.10 1.22 1.10 1.22
--(0.86 - 1.41)(0.95 - 1.55)(0.82 - 1.47)(0.93 - 1.58)
In school or working 0.82* (0.83 - 0.98)
Ever Pregnant 1.10* (0.95 - 1.28)
Does not want pregnancy in next 2 years or ever 0.94 (0.82 - 1.09)
Very sure will use BC for 1 year 0.73*** (0.64 - 0.83)
Endorsed negative BC attributes 1.18 (1.00 - 1.39)
Main Partner very much against use of any hormonal BC 1.20 (0.99 - 1.47)
Peers very much against use of any hormonal BC 0.90 (0.73 - 1.10)
*P< 0.05 **p<0.01 ***p<0.001 Excludes 49 women who had missing information on independent variables
Main Reason for Discontinuation N=991
Pill (%)
Patch (%)
Ring (%)
DMPA (%)
Total (%)
Side effects 33 35 26 46 36Access/supply/cost barriers 9 8 10 17 11Not sexually active/No need 15 8 11 11 11Difficulties with use 20 9 14 1 11Pregnancy related 5 9 8 3 6Medical/health concerns 4 6 6 3 4Wanted to become pregnant
2 1 2 2 2
Other reasons* 14 25 25 20 21
Excludes 278 women who did not discontinue the baseline method.Pearson Chi-square (18) = 97.9 P ≤ 0.001
Pregnancies (per 100 person years)By Method Selected and Contraceptive Use Pattern
Contraceptive Use Pattern
Continuation of Method Selected**
n=325 (25%)
Discontinuation of Method Selected
With Switch toAnother Effective Method
n=738 (56%)
Discontinuation ofMethod Selected
Without Subsequent Use of Another Effective Method
n=253 (19%)
Pill 4.4 19.2 34.5 16.5
Patch 19.6 28.8 39.1 30.1
Ring 12.4 34.3 52.7 30.5
DMPA 5.7 17.1 20.4 16.1
Total 9.1 23.9 37.2 22.9
**46% of women in this category (n=144) reported taking breaks
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
Summary• Contraceptive Method independently
associated with discontinuation• Contraceptive Continuation at 12 months low
for all method initiators; lowest for Patch and DMPA initiators however.
Pill 32.7
Patch 12.1
Ring 29.4
DMPA 10.9
Women per 100 Person Years
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
Summary• Other factors independently associated with
continuation:– Being very sure/intent on using the
method selected– Older age– Being in school or employed
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
Summary• Pregnancy rate associated with:
– Method Selected– Switching– Breaks– Discontinuation
• DMPA initiators had higher discontinuation rate but pregnancy rate comparable to pill initiators
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
Limitations
• Generalizability– Study conducted in Northern California
(suburban, uninsured women) - may not be generalizable to other populations
• Study Design– Observational study – women selected BC
methods; difficult to measure “selection bias” (i.e. bad or good contraceptors selected or given certain methods)
• Social Desirability Bias– Self-report data and biological markers used
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
Conclusions - Implications
• Access isn’t enough
– 12-month contraceptive continuation was low for this cohort of women with minimal access barriers
• New delivery systems not fulfilling the promise
– While they provide women with more options, the patch and the ring may not be better options than the pill or DMPA for high-risk women
Department of Obstetrics, Gynecology & Reproductive
Sciences
School of Medicine
Conclusions - Implications
• Intent matters – Providers may be able ask patients very simple
questions to identify women at risk for contraceptive discontinuation
• Improved understanding of contraceptive intent is needed
• Context matters– Age, employment, school important
• Unclear if these factors can be addressed with clinic interventions
• Improved understanding of what providers do is needed
Many Thanks to the staff of the Golden Gate and Shasta Diablo Planned Parenthood Affiliates
for their assistance in conducting this study
Questions – Contact Dr. Tina [email protected]