Maximizing the effectiveness of 1.5 mg levonorgestrel for emergency contraception: The case for precoital use.

Objectives: U.S. and World Health Organization Selected Practice Recommendations for Contraceptive Use state people may have an advanced supply of emergency contraception (EC) to minimize treatment delays. We sought to characterize the potential improvement in effectiveness of 1.5 mg levonorgestrel (LNG-EC) if it were taken up to a few hours before unprotected sex. Study design: We expanded on an existing mathematical model for the maximum attainable effectiveness of LNG-EC, assuming it exclusively works to disrupt ovulation, and compared results with point estimates from nine studies when it was taken up to 72 hours after sex. We then modelled how effectiveness might have improved if subjects had taken LNG-EC up to 3 hours before sex. Results: Taking LNG-EC immediately after sex could potentially reduce the risk of unintended pregnancy by 91%. However, population-average maximum attainable effectiveness levels ranged from just 49% to 67% when accounting for the distributions of postcoital treatment delays in the example studies. If half the subjects had taken it 3 hours before sex, then maximum effectiveness levels would have ranged from 70% to 81%. Conclusions: At the individual level, taking LNG-EC a few hours before sex is a logical extension of Selected Practice Recommendations regarding an advanced supply of EC and, based on our modeling, should be advocated for people who can reasonably anticipate an unprotected sex act. In the absence of more clinical data, however, people should not routinely rely on precoital use of LNG-EC to prevent pregnancy unless modern, effective contraceptives are inaccessible to them. Implications: Based on mathematical modeling, individuals who anticipate needing to take LNG-EC for an impending unprotected act of sex could further reduce their chance of an undesired pregnancy by taking it a few hours in advance.

Couple-Years of Protection Indicator: New Global Guidance for Updating Existing Methods and Adding New Methods.

BACKGROUND: Couple-years of protection (CYP) is an indicator that allows for monitoring and evaluating of family planning (FP) program performance through simple calculations. The CYP for each contraceptive method is calculated by multiplying the number of contraceptive commodity units distributed to clients over a 1-year period by a conversion factor that quantifies the duration of contraceptive protection provided per unit distributed. CYP calculations across methods were previously updated in 2000 and 2011, resulting in changes in methodology, factor inclusion, and specific methods. Since the 2011 update, changes and additions to the modern contraceptive method mix required new CYP conversion factors for 4 methods of contraception: Levoplant implant, progestin-only pills (POPs), Caya diaphragm, and the hormonal intrauterine device. METHODS: We conducted literature reviews of both published and gray literature and consulted with experts to identify updated data on continuation rates, duration of efficacy, and method effectiveness for the 4 methods. New CYP conversion factors were calculated for the 4 methods either by using the same calculation used previously for the method considering new data or, for new methods, using calculations for similar methods. RESULTS: New CYP conversion factors were assigned to the 4 methods of contraception covered in this update: Levoplant, 2.5 CYP per implant inserted; POPs, 0.0833 CYP per pack (i.e., 12 cycles per CYP); Caya diaphragm, 1 CYP per device, and hormonal intrauterine device, 4.8 CYP per device inserted. CONCLUSIONS: CYP is an important indicator for FP programs. As new methods of contraception are developed and new evidence is generated for current methods, the indicator may need to be updated. A standard process for updating and documenting future CYP updates is recommended.

Post-randomization Differences in Condomless Vaginal Sex Among Women Randomized to Intramuscular Depot Medroxyprogesterone Acetate Injections, a Copper Intrauterine Device or a Levonorgestrel Implant in the ECHO Trial.

The Evidence for Contraceptive Options and HIV Outcomes (ECHO) trial found no substantial difference in HIV acquisition risk between women randomised to injectable intramuscular depot medroxyprogesterone acetate (DMPA-IM), copper intrauterine device (Cu-IUD) or the levonorgestrel (LNG) implant. We evaluated post-randomization sexual behavior using an objective marker of condomless vaginal sex in a subset of participants. We conducted a sub-study among 458 ECHO participants at three sites (Cape Town, Johannesburg, Kisumu) to evaluate the frequency of condomless vaginal sex, measured by prostate specific antigen (PSA) detection in vaginal swabs, collected at the month 6 and final visit and the concordance of self-reported condomless vaginal sex with PSA detection, by randomized arm. We compared PSA detection frequency and concordance of PSA and self-reported condomless vaginal sex, by randomized group using Cochran-Mantel-Haenszel tests and adjusted generalized logistic growth curve models. PSA was detected less frequently in the DMPA-IM (16%), compared to the Cu-IUD (21%) and LNG implant (24%) groups, although results were not statistically significant in the unadjusted model when accounting for pre-specified multiple-testing criteria. There were significant differences in PSA detection between the DMPA-IM and LNG-implant groups (odds ratio 0.61 (95% CI 0.40, 0.94) in the adjusted model. There was moderate discordance between self-reported condomless vaginal sex and detection of PSA that was similar across randomized groups. These data suggest that women randomized to Cu-IUD and LNG implant may have had condomless sex more frequently than women randomized to DMPA-IM. The discordance between detectable PSA and self-reported sexual behaviour has important implications for design of future HIV prevention studies.

What Have We Learned? Implementation of a Shared Learning Agenda and Access Strategy for the Hormonal Intrauterine Device.

In 2015, a global learning agenda for the hormonal intrauterine device (IUD) was developed with priority research questions regarding use of the method in low- and middle-income countries. In addition, members of the Hormonal IUD Access Group aligned on a strategy to expand access in the context of volunteerism and contraceptive method choice. This article synthesizes evidence generated since then and describes steps taken to address demand- and supply-side barriers to access. Findings demonstrated high continuation rates and satisfaction among hormonal IUD users that are comparable to other long-acting reversible contraceptives (LARCs). Across studies, a sizable number of users reported they would have chosen a short-acting method or no method at all if the hormonal IUD were not an option, which suggests that women did not see the hormonal IUD as interchangeable with other LARC options and thus it may fill an important niche in the market. With several countries now poised to scale up the method, resource mobilization will be key. On the demand side, investments in implementation research will be critical to understanding how best to launch and scale the method, while ensuring the sustainability of multiple quality-assured suppliers with affordable public-sector pricing will be necessary on the supply side.

Debunking myths about contraceptive safety among women in Kingston, Jamaica: Pilot randomized controlled trial.

OBJECTIVES: (1) To create a short motion graphic video to debias women, using evidence from cognitive psychology, of 2 common myths about safety of intrauterine devices (IUDs) and implants in Jamaica; and (2) to conduct a pilot study to evaluate video effectiveness. STUDY DESIGN: We conducted a series of 3 focus group discussions among target users to inform the development process of the script, story, character, and look of the intervention video. We randomized young, female nonusers of long-acting contraception at risk of pregnancy at a public clinic in Kingston in 2018-2019 to watch either the intervention (n = 113) or control video (n = 112). We used logistical regression to evaluate perceptions of method safety, naturalness, and uptake after 3 months of follow up. RESULTS: Almost all (n = 220; 97.8%) participants completed the 3-month interview. More women in the intervention arm perceived IUDs to be safe (59.1%) compared to the control arm (43.6%; p = 0.02). Perceived implant safety increased from enrollment to follow up in the intervention and control arms (10.9 and 2.7 percentage-point increases, respectively); however, the difference between arms at follow up was not statistically significant (p = 0.57). This appeared to be due to arm imbalances at enrollment. Study arms did not differ at follow up in perceived IUD naturalness (p = 0.36) or implant naturalness (p = 0.68). CONCLUSIONS: Findings from a pilot study of a video intervention suggest that using debiasing strategies from cognitive psychology has the potential to address misconceptions about contraceptive safety. A larger trial with adequate power is warranted. IMPLICATIONS: Evidence from a pilot randomized controlled trial suggested that use of debiasing strategies from cognitive psychology could be effective in correcting women's misconceptions about contraception safety and thus show promise for the design of future contraceptive promotion videos to increase uptake.

Contraceptive knowledge among women at risk of unintended pregnancy in Kingston, Jamaica.

Low contraceptive knowledge may limit contraception initiation or continuation and, consequently, could represent an important, modifiable cause of unintended pregnancy. The objective of this analysis was to identify correlates of knowledge among women at risk of unintended pregnancy. We analyzed data from a study of 222 young women attending a public clinic in Kingston in November 2018 to March 2019. We measured contraceptive knowledge with seven questions on method reversibility, ability to use covertly, contraindications, and side effects. We used multivariable linear regression to evaluate the correlates of summary knowledge scores and report beta coefficients, which represent differences in mean summary knowledge scores. The mean knowledge score was low (2.7; range = 0-7). Only 30.2% of the participants correctly identified intrauterine devices as more effective than oral contraception, male condoms, and withdrawal. Women who reported that their provider discussed contraception scored higher (adjusted ß = 0.37, p = 0.05) than those not reporting this. Women who perceived implants as very/mostly safe scored higher (adjusted ß = 0.45, p = 0.01) than those perceiving the device as mostly/very unsafe. Finally, compared to contraception non-users, women using less-effective contraception had a lower score (adjusted ß = -0.40, p = 0.04) while those using effective contraception did not differ in scores (ß = -0.30, p = 0.18). Overall, we found poor contraceptive knowledge among young women in Kingston. Providers appeared to hold an important role in women's understanding of contraception.

What's Sex Got to Do With It? Understanding Potential Confounding and Exposure Misclassification in Mechanistic Sexually Transmitted Infection Research.

We conducted a prospective study of 13 heterosexual couples to understand the impact of recent condomless vaginal sex on vaginal immune marker measurement and potential exposure misclassification due to the presence of semen. All immune markers were detectable in semen and concentrations of vaginal immune markers varied by sex recency.

Levonorgestrel release rates measured through analysis of two-rod contraceptive explants.

OBJECTIVE: The objective was to characterize and compare in vivo rates of levonorgestrel (LNG) release from Sino-implant (II) and Jadelle® contraceptive implants. STUDY DESIGN: We sampled 48 Sino-implant (II) and 49 Jadelle® explant sets for residual LNG content from participants treated for up to 51 months in a randomized contraceptive efficacy trial in the Dominican Republic (DR). Additional Sino-implant (II) explants were obtained from 8 women who became pregnant in the DR trial and 10 who contributed 3 to 5 years of use in a cohort study in China. Baseline LNG loads were estimated from five unused implant sets per device type. Release profiles were estimated using mixture models that captured initial burst fractions and compared with efficacy and pharmacokinetics data from the DR trial. RESULTS: Estimated baseline LNG loads for Sino-implant (II) and Jadelle® were 142.8 mg and 150.5 mg, respectively (vs. the labeled 150 mg). There was an initial burst release of drug (5.6% and 7.9%, respectively) followed by an exponential decrease in LNG content evident for each device. Release rates were significantly lower for Sino-implant (II) throughout the treatment period, with estimated rates after 3 years of 24.2 mcg/day and 29.0 mcg/day for Sino-implant (II) and Jadelle®, respectively. The estimated Sino-implant (II) rate after 3 years was similar to the predicted rate after 5 years (23.6 mcg/day) for Jadelle® (rate ratio: 1.03; 95% confidence interval: 0.92-1.13). CONCLUSIONS: Sino-implant (II) LNG release rates were significantly lower than Jadelle® with Sino-implant (II) rates through year 3 comparable to Jadelle® rates through year 5. These results reinforce the 3-year duration of action for which Sino-implant (II) was prequalified by the World Health Organization. IMPLICATIONS: This analysis confirms the WHO prequalification of Sino-implant (II) for 3 years of use and supports different durations of action for Jadelle® and Sino-implant (II). It provides additional evidence that this approach can complement efficacy trials in determining duration of action of hormonal contraceptives in general.

Planning for Outcomes (P4O) Modeling Tool: Estimating the Impact of Changing the Proportion of Injectable Progestins in the Contraceptive Method Mix.

BACKGROUND: Observational studies raise concern about a potential link between injectable progestin contraceptive use and HIV acquisition risk. This possible link is particularly relevant in sub-Saharan Africa where HIV risk is high and the method mix is skewed toward injectables. We developed the Planning for Outcomes (P4O) model (https://planning4outcomes.ctiexchange.org/) to predict changes in maternal and child health (MCH) and HIV outcomes that could occur if the proportion of injectables in the method mix is changed. METHODS: P4O incorporates evidence-based assumptions to predict yearly changes in unintended pregnancies, morbidity/mortality, HIV infections (women and infants), and anticipated health care costs associated with changing the proportions of injectable users in 22 selected countries. Users of this model designate all countries or a subset and adjust inputs including percentage of injectable users who discontinue, percentage of discontinuers who begin use of an alternative method, hazard ratio for HIV infection with injectable use, method mix used by injectable discontinuers, annual probabilities of method-specific pregnancy and mother-to-child transmission of HIV, condom effectiveness against HIV, risk of HIV during pregnancy, and HIV incidence among women of reproductive age. RESULTS: Illustrative results from all sub-Saharan African countries combined and from selected countries demonstrate the potential of P4O to inform program planning and procurement decisions. In countries with high use of long-acting reversible contraception, the removal of injectables from the method mix is associated with improvement in MCH and HIV indicators if most injectable users switch to more effective methods (e.g., implants). In countries with high use of short-acting methods (e.g., condoms), the model predicts mostly negative MCH outcomes. CONCLUSIONS: Policy makers and program planners may use P4O to inform programming and policy decisions. In all scenarios, programmatic preparation to accommodate changes to the contraceptive method mix, considerations of how the individual desires of women will be addressed, and potential burden of anticipated MCH-related costs warrant advanced consideration.

Electronic interventions for changing knowledge, attitudes or practices regarding contraception: a systematic review.

OBJECTIVES: We conducted a systematic review of the effectiveness of electronic health education tools designed to improve knowledge, attitudes or practices related to contraception. METHODS: Eligible studies consisted of English-language reports published after 1990 that quantified the effects of an electronic intervention on any of the following outcomes: contraceptive knowledge, attitude toward contraceptives, contraceptive method choice, contraceptive use or pregnancy. We conducted a systematic search of multiple electronic databases including MEDLINE, Global Health, Academic Search Complete, Cochrane Library and Grey Literature Report. We followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for reporting. RESULTS: Of 143 full-text reports assessed for eligibility, 13 studies described in 16 reports were eligible for inclusion. Of six studies that evaluated video interventions, all were randomized controlled trials, and four reported any statistically significant difference between intervention groups on knowledge, method choice or pregnancy. Of seven studies of interactive computer applications, five were randomized controlled trials, and two were nonrandomized comparison studies. Four of these seven studies found statistically significant difference between study arms in contraceptive knowledge, attitudes or contraceptive use. While most differences favored the intervention, effects were generally limited with respect to clinical relevance and the number of outcomes impacted. CONCLUSIONS: Published assessments of electronic interventions for improving contraception-related outcomes are limited. Formal evaluations of interventions and publication of results are needed to determine the efficacy of electronic tools for contraceptive education and guide development of new interventions.

Knowledge of contraceptive effectiveness and method use among women in Hanoi, Vietnam.

OBJECTIVE: To evaluate the association between contraceptive knowledge and type of method used. METHODS: We analyzed data from a cross-sectional study of sexually active women in Hanoi, Vietnam, not desiring pregnancy. We used linear and logistic regression to evaluate contraceptive knowledge of users of the intrauterine device (IUD), combination oral contraception (COC) and male condoms. We measured contraceptive knowledge with seven questions on relative effectiveness of methods, reversibility, covert use, contraindications and side effects. RESULTS: Respondents used IUD (n = 128), COC (n = 126) or condoms (n = 167). Summary knowledge scores did not differ by current type of method used. Only one knowledge domain, contraceptive effectiveness, varied by method. Compared to condom users, IUD users had higher odds of correctly identifying the IUD as more effective than COC, condoms and withdrawal (adjusted odds ratio [aOR], 4.8; 95% confidence interval [CI], 2.7-8.3). Higher proportions of condom users (49.7%) mistakenly identified condoms as the most effective of listed methods compared to IUD (20.3%) and COC users (23.0%). On the other hand, IUD and COC users had lower odds (aOR, 0.5; 95% CI, 0.2-1.0 and aOR, 0.3; 95% CI, 0.1-0.6, respectively) of identifying consistent condom use as better for pregnancy prevention than other practices (e.g., withdrawal and postcoital douching). CONCLUSIONS: IUD users more often recognized that the IUD is highly effective while condom users appeared to overestimate condom effectiveness. Contraceptive counseling should ensure that women understand the relative effectiveness of methods. We found no evidence that other types of contraceptive knowledge differed by type of method used. IMPLICATIONS: Knowledge of contraceptive effectiveness was the sole difference detected in contraceptive knowledge between women in Hanoi, Vietnam, using the IUD, COC or male condoms.

Sexual Relationship Power and Semen Exposure Among Female Patients at a Sexually Transmitted Infection Clinic in Kingston, Jamaica.

Women's power in sexual relationships is thought to be an important predictor of condom use. However, research on correlates of condom use often relies on participant reporting of behavior, which has questionable validity. We evaluated the association between scores from the modified Sexual Relationship Power Scale (SRPS-M) and biological detection of semen exposure in a prospective study of adult women attending a sexually transmitted infection clinic in Kingston, Jamaica with cervicitis or abnormal vaginal discharge in 2010-2011. At enrollment, women were counseled to avoid sex while on treatment and were asked to return in 6 days for a follow-up visit. At both study visits, women were administered a questionnaire and had vaginal swabs collected to test for prostate-specific antigen (PSA), a biological marker of recent semen exposure. We found no significant association at enrollment or follow-up between SRPS-M scores and semen exposure, as measured with either self-reported data or PSA positivity. Semen biomarkers could be used to develop and validate new scales on relationship power and self-efficacy related to condom use.

Expanding Access to a New, More Affordable Levonorgestrel Intrauterine System in Kenya: Service Delivery Costs Compared With Other Contraceptive Methods and Perspectives of Key Opinion Leaders.

BACKGROUND: The levonorgestrel intrauterine system (LNG IUS) is one of the most effective forms of contraception and offers important non-contraceptive health benefits. However, it is not widely available in developing countries, largely due to the high price of existing products. Medicines360 plans to introduce its new, more affordable LNG IUS in Kenya. The public-sector transfer price will vary by volume between US$12 to US$16 per unit; for an order of 100,000 units, the public-sector transfer price will be approximately US$15 per unit. METHODS: We calculated the direct service delivery cost per couple-years of protection (CYP) of various family planning methods. The model includes the costs of contraceptive commodities, consumable supplies, instruments per client visit, and direct labor for counseling, insertion, removal, and resupply, if required. The model does not include costs of demand creation or training. We conducted interviews with key opinion leaders in Kenya to identify considerations for scale-up of a new LNG IUS, including strategies to overcome barriers that have contributed to low uptake of the copper intrauterine device. RESULTS: The direct service delivery cost of Medicines360's LNG IUS per CYP compares favorably with other contraceptive methods commonly procured for public-sector distribution in Kenya. The cost is slightly lower than that of the 3-month contraceptive injectable, which is currently the most popular method in Kenya. Almost all key opinion leaders agreed that introducing a more affordable LNG IUS could increase demand and uptake of the method. They thought that women seeking the product's non-contraceptive health benefits would be a key market segment, and most agreed that the reduced menstrual bleeding associated with the method would likely be viewed as an advantage. The key opinion leaders indicated that myths and misconceptions among providers and clients about IUDs must be addressed, and that demand creation and provider training should be prioritized. CONCLUSION: Introducing a new, more affordable LNG IUS product could help expand choice for women in Kenya and increase use of long-acting reversible contraception. Further evaluation is needed to identify the full costs required for introduction-including the cost of demand creation-as well as research among potential and actual LNG IUS users, their partners, and health care providers to help inform scale-up of the method.

Association of Progestin Contraceptive Implant and Weight Gain.

OBJECTIVE: To evaluate initiation of a two-rod, 150-mg levonorgestrel contraceptive implant on women's perceived and observed body weight. METHODS: We conducted a secondary analysis of data from an open, randomized controlled trial of adult, nonpregnant, human immunodeficiency virus-negative women attending a public clinic in Kingston, Jamaica, who were assigned to initiate implant use either immediately or after a 3-month delay. The primary objective of the parent study was to assess the effect of initiation of the implant on the frequency of condom use. We compared study arms during follow-up using one-sided χ tests for differences in perceived weight gain and loss, one-sided Wilcoxon-Mann-Whitney tests for median gain in measured weight, and logistic regression with generalized estimating equations for risk of gaining greater than 2 kg. RESULTS: From 2012 to 2014, women were assigned to the implant (n=208) or delay arm (n=206). At 3 months, more women in the implant arm (15.3%) reported perceived weight gain than in the control arm (4.3%) (P=.01). Despite differences in perception, the implant and control arms did not differ significantly in median weight gain at 1-month (0.0 kg and 0.0 kg, respectively; P=.44) and 3-month visits (0.5 kg and 0.0 kg, respectively; P=.27). Study arms did not differ in risk of gaining greater than 2 kg (odds ratio 0.9, 95% confidence interval 0.6-1.3). CONCLUSION: We found no evidence of weight gain from short-term implant use. Through the power of the nocebo effect, the practice of counseling women to expect possible weight gain from initiating implant use could lead them to perceive weight gain even in its absence and contribute to the early discontinuation of this highly effective contraceptive method.

In vivo release of levonorgestrel from Sino-implant (II) ­ an innovative comparison of explant data.

OBJECTIVES: Measuring the amount of progestin remaining in contraceptive implants used for different lengths of time provides useful information on in vivo release kinetics including change over time. We compared estimated in vivo levonorgestrel (LNG) release rates derived from Sino-implant (II) explants with similar data from removed Jadelle. STUDY DESIGN: We measured LNG remaining in 44 sets of Sino-implant (II) used for up to 7 years and removed in four Chinese clinics. Results were compared with published data for Jadelle explants used for up to 36 months. We estimated and compared monthly and daily LNG release rates for the two products using prediction models for drug release. We also estimated the dissolution profile similarity factor, f2, for LNG release. RESULTS: Both Sino-implant (II) and Jadelle release approximately 30% of total LNG load after 3 years. Results of fitting the data to a biologically plausible modified Higuchi prediction model indicate comparable release through 3 years. An estimated similarity factor of 80.6 (90% confidence interval: 70.8-85.7) indicates similarity in the dissolution profiles of the two implants. CONCLUSIONS: LNG release in vivo measured through explant analysis suggest that Sino-implant (II) and Jadelle may perform similarly through 3 years of use and could remain highly effective beyond this time point. These results align with published data for Jadelle and Sino-implant (II) showing high effectiveness for 5 years. Ongoing clinical studies comparing the products over 5 years present an opportunity to verify this supportive measure of clinical effectiveness. IMPLICATIONS: This innovative approach provides evidence that Sino-implant (II) may perform clinically similarly to Jadelle over 3 years and remain a highly effective contraceptive beyond this time point. Data from explant analyses show promise for investigating the equivalence of elusion profiles of contraceptive implants.

Effects of initiating a contraceptive implant on subsequent condom use: A randomized controlled trial.

OBJECTIVE: To evaluate whether initiation of a contraceptive implant, a method of long-acting reversible contraception, reduces condom use, as measured by a biomarker of recent semen exposure [prostate-specific antigen (PSA)]. STUDY DESIGN: We conducted a randomized controlled clinical trial in which 414 Jamaican women at high risk for sexually transmitted infections (STIs) attending family planning clinics received the contraceptive implant at baseline ("immediate" insertion arm, N=208) or at the end ("delayed" insertion arm, N=206) of a 3-month study period. Participants were tested for PSA at baseline and two follow-up study visits and were asked about their sexual activity and condom use. RESULTS: At baseline, 24.9% of women tested positive for PSA. At both follow-up visits, the prevalence of PSA detection did not significantly differ between the immediate versus delayed insertion arm [1-month: 26.1% vs. 20.2%, prevalence ratio (PR)=1.3, 95% confidence interval (CI)=0.9-1.9; 3-month: 25.6% vs. 23.1%, PR= 1.1, 95% CI=0.8-1.6]. The change in PSA positivity over the three study visits was not significantly larger in the immediate arm compared to the delayed arm (1-sided p-value of .15). CONCLUSIONS: Contraceptive implants can be successfully introduced into a population at high risk of unintended pregnancy and STIs without a biologically detectable difference in unprotected sex in the short term. This information strengthens the evidence to support promotion of implants in such populations and can help refine counseling for promoting and maintaining use of condoms among women who choose to use implants. IMPLICATIONS: Sex unprotected by a condom was not higher over 3 months in women receiving a contraceptive implant, compared with those not receiving the implant.

Differences in misreporting of sexual behavior over time: implications for HIV trials.

We used data from a prospective study of 300 women attending a sexually transmitted infection clinic in Kingston, Jamaica, to compare participant self-report of recent semen exposure to actual semen exposure measured by prostate-specific antigen in vaginal swabs. Underreporting of semen exposure was significantly more frequent at follow-up than baseline, suggesting that the accuracy of reports of sexual behavior may vary over time.

Sino-implant (II)® continuation and effect of concomitant tenofovir disoproxil fumarate-emtricitabine use on plasma levonorgestrel concentrations among women in Bondo, Kenya.

OBJECTIVE: The objective was to assess associations between tenofovir disoproxil fumarate-emtricitabine (TDF-FTC) exposure and levonorgestrel (LNG) concentrations among Kenyan HIV prevention trial participants using Sino-implant (II) LNG implants for contraception. METHODS: Women were offered implants among other contraceptive methods, were randomized to daily TDF-FTC or placebo, and followed monthly up to 56weeks. Associations between TDF-FTC exposure and mean LNG values were analyzed with linear mixed models. RESULTS: Of 739 women, 29 (3.9%) received implants with no incident pregnancies and one discontinuation. Mean LNG concentrations over 56weeks among 28 women contributing data ranged between 214.0 and 659.8pg/mL with no significant difference between TDF-FTC and placebo arms or between variable levels of TDF-FTC adherence. CONCLUSION: Concomitant TDF-FTC use was not associated with a significant change in plasma LNG concentrations among women using Sino-implant (II) in the first year of use.