Contraceptive efficacy, safety, fit, and acceptability of a single-size diaphragm developed with end-user input.
OBJECTIVE
To estimate contraceptive efficacy, safety, acceptability, and fit of a single-size diaphragm used with contraceptive gel.


METHODS
We conducted a multicenter trial in which 450 couples used the single-size diaphragm, 300 randomized to acid-buffering gel and 150 to nonoxynol-9, for at least 190 days and six menstrual cycles. Visits were at enrollment and after menstrual cycles 1, 3, and 6. Study outcomes included pregnancy probability, safety, acceptability, and fit. Pregnancy and safety were compared with an historical control group who used a standard diaphragm with these gels.


RESULTS
Most (439/450 [98%]) women could be fitted with the single-size diaphragm. A total of 421 of 450 (94%) provided follow-up. The 35 study pregnancies yielded 6-month Kaplan-Meier cumulative typical use pregnancy probabilities per 100 women with 95% confidence intervals (CIs) of 10.4 (6.9-14.0) for all users and 9.6 (5.5-13.6) and 12.5 (5.4-19.5) with acid-buffering gel and nonoxynol-9, respectively. Historical control analysis yielded a propensity score-adjusted estimate of this pregnancy probability for the single-size diaphragm of 11.3 compared with 10.7 per 100 women for the standard diaphragm ([rounded] difference 0.7, 95% CI -3.6 to 4.9). Approximately half (51%) reported at least one urogenital event but compared favorably to the standard diaphragm in historical control analysis. Most (282/342 [82%]) liked the diaphragm. Results suggest that if provided by a clinician, 94% (95% CI 92-96%) could insert, correctly position, and remove the diaphragm.


CONCLUSIONS
The single-size diaphragm was safe, as effective as a standard diaphragm, and acceptable when used with contraceptive gel.


BACKGROUND
ClinicalTrials.gov, www.clinicaltrials.gov, NCT00578877.
CONRAD, Eastern Virginia Medical School, Arlington, Virginia; FHI 360, Durham, North Carolina; the California Family Health Council, Los Angeles, California; the University of Pittsburgh, Pittsburgh, Pennsylvania; Johns Hopkins Community Physicians, Baltimore, Maryland; the University of Pennsylvania, Philadelphia, Pennsylvania; Baylor College of Medicine, Houston, Texas; and PATH, Seattle, Washington. Dr. Creinin is currently affiliated with the University of California, Davis, Sacramento, California.
Jill L
JL
Schwartz
Debra H
DH
Weiner
Jaim Jou
JJ
Lai
Ron G
RG
Frezieres
Mitchell D
MD
Creinin
David F
DF
Archer
Lynn
L
Bradley
Kurt T
KT
Barnhart
Alfred
A
Poindexter
Maggie
M
Kilbourne-Brook
Marianne M
MM
Callahan
Christine K
CK
Mauck
D000180:Acrylic Resins / Q000009:adverse effects; D000328:Adult; D003274:Contraceptive Devices, Female / Q000009:adverse effects; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D017137:Nonoxynol / Q000009:adverse effects; D017060:Patient Satisfaction; D011247:Pregnancy / Q000706:statistics & numerical data*; D057216:Propensity Score; D013089:Spermatocidal Agents / Q000009:adverse effects; D014622:Vaginal Creams, Foams, and Jellies / Q000009:adverse effects; D055815:Young Adult
D000180:Acrylic Resins; C420918:BufferGel; D013089:Spermatocidal Agents; D014622:Vaginal Creams, Foams, and Jellies; D017137:Nonoxynol