Naproxen or estradiol for bleeding and spotting with the levonorgestrel intrauterine system: a randomized controlled trial

Interventions to prevent or treat heavy menstrual bleeding or pain associated with intrauterine-device use

BACKGROUND

Heavy menstrual bleeding and pain are common reasons women discontinue intrauterine device (IUD) use. Copper IUD (Cu IUD) users tend to experience increased menstrual bleeding, whereas levonorgestrel IUD (LNG IUD) users tend to have irregular menstruation. Medical therapies used to reduce heavy menstrual bleeding or pain associated with Cu and LNG IUD use include non-steroidal anti-inflammatory drugs (NSAIDs), anti-fibrinolytics and paracetamol. We analysed treatment and prevention interventions separately because the expected outcomes for treatment and prevention interventions differ. We did not combine different drug classes in the analysis as they have different mechanisms of action. This is an update of a review originally on NSAIDs. The review scope has been widened to include all interventions for treatment or prevention of heavy menstrual bleeding or pain associated with IUD use.

OBJECTIVES

To evaluate all randomized controlled trials (RCTs) that have assessed strategies for treatment and prevention of heavy menstrual bleeding or pain associated with IUD use, for example, pharmacotherapy and alternative therapies.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase and CINAHL to January 2021.

SELECTION CRITERIA

We included RCTs in any language that tested strategies for treatment or prevention of heavy menstrual bleeding or pain associated with IUD (Cu IUD, LNG IUD or other IUD) use. The comparison could be no intervention, placebo or another active intervention.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and risk of bias, and extracted data. Primary outcomes were volume of menstrual blood loss, duration of menstruation and painful menstruation. We used a random-effects model in all meta-analyses. Review authors assessed the certainty of evidence using GRADE.

MAIN RESULTS

This review includes 21 trials involving 3689 participants from middle- and high-income countries. Women were 18 to 45 years old and either already using an IUD or had just had one placed for contraception. The included trials examined NSAIDs and other interventions. Eleven were treatment trials, of these seven were on users of the Cu IUD, one on LNG IUD and three on an unknown type. Ten were prevention trials, six focused on Cu IUD users, and four on LNG IUD users. Sixteen trials had high risk of detection bias due to subjective assessment of pain and bleeding. Treatment of heavy menstrual bleeding Cu IUD Vitamin B1 resulted in fewer pads used per day (mean difference (MD) -7.00, 95% confidence interval (CI) -8.50 to -5.50) and fewer bleeding days (MD -2.00, 95% CI -2.38 to -1.62; 1 trial; 110 women; low-certainty evidence) compared to placebo. The evidence is very uncertain about the effect of naproxen on the volume of menstruation compared to placebo (odds ratio (OR) 0.09, 95% CI 0.00 to 1.78; 1 trial, 40 women; very low-certainty evidence). Treatment with mefenamic acid resulted in less volume of blood loss compared to tranexamic acid (MD -64.26, 95% CI -105.65 to -22.87; 1 trial, 94 women; low-certainty evidence). However, there was no difference in duration of bleeding with treatment of mefenamic acid or tranexamic acid (MD 0.08 days, 95% CI -0.27 to 0.42, 2 trials, 152 women; low-certainty evidence). LNG IUD The use of ulipristal acetate in LNG IUD may not reduce the number of bleeding days in 90 days in comparison to placebo (MD -9.30 days, 95% CI -26.76 to 8.16; 1 trial, 24 women; low-certainty evidence). Unknown IUD type Mefenamic acid may not reduce volume of bleeding compared to Vitex agnus measured by pictorial blood assessment chart (MD -2.40, 95% CI -13.77 to 8.97; 1 trial; 84 women; low-certainty evidence). Treatment of pain Cu IUD Treatment with tranexamic acid and sodium diclofenac may result in little or no difference in the occurrence of pain (OR 1.00, 95% CI 0.06 to 17.25; 1 trial, 38 women; very low-certainty evidence). Unknown IUD type Naproxen may reduce pain (MD 4.10, 95% CI 0.91 to 7.29; 1 trial, 33 women; low-certainty evidence). Prevention of heavy menstrual bleeding Cu IUD We found very low-certainty evidence that tolfenamic acid may prevent heavy bleeding compared to placebo (OR 0.54, 95% CI 0.34 to 0.85; 1 trial, 310 women). There was no difference between ibuprofen and placebo in blood volume reduction (MD -14.11, 95% CI -36.04 to 7.82) and duration of bleeding (MD -0.2 days, 95% CI -1.40 to 1.0; 1 trial, 28 women, low-certainty evidence). Aspirin may not prevent heavy bleeding in comparison to paracetamol (MD -0.30, 95% CI -26.16 to 25.56; 1 trial, 20 women; very low-certainty evidence). LNG IUD Ulipristal acetate may increase the percentage of bleeding days compared to placebo (MD 9.50, 95% CI 1.48 to 17.52; 1 trial, 118 women; low-certainty evidence). There were insufficient data for analysis in a single trial comparing mifepristone and vitamin B. There were insufficient data for analysis in the single trial comparing tranexamic acid and mefenamic acid and in another trial comparing naproxen with estradiol. Prevention of pain Cu IUD There was low-certainty evidence that tolfenamic acid may not be effective to prevent painful menstruation compared to placebo (OR 0.71, 95% CI 0.44 to 1.14; 1 trial, 310 women). Ibuprofen may not reduce menstrual cramps compared to placebo (OR 1.00, 95% CI 0.11 to 8.95; 1 trial, 20 women, low-certainty evidence).

AUTHORS' CONCLUSIONS

Findings from this review should be interpreted with caution due to low- and very low-certainty evidence. Included trials were limited; the majority of the evidence was derived from single trials with few participants. Further research requires larger trials and improved trial reporting. The use of vitamin B1 and mefenamic acid to treat heavy menstruation and tolfenamic acid to prevent heavy menstruation associated with Cu IUD should be investigated. More trials are needed to generate evidence for the treatment and prevention of heavy and painful menstruation associated with LNG IUD.

Management of bothersome bleeding associated with progestin-based long-acting reversible contraception: a review

PURPOSE OF REVIEW

To describe common bleeding patterns and treatment strategies to minimize bothersome bleeding in users of progestin-based long-acting reversible contraception (LARC).

RECENT FINDINGS

Most levonorgestrel intrauterine device users will establish a favorable bleeding pattern within a year; NSAIDs are the most effective bridge to help with bothersome bleeding during that time period. Early follicular phase insertion and fundal placement are associated with more favorable early bleeding profiles. Recent studies exploring tranexamic acid, mifepristone, and tamoxifen's adjunct role show modest or no benefit. The progestin implant is associated with more persistent unpredictable bleeding disproportionately affecting women with higher etonogestrel serum levels; recent studies indicate that oral contraceptives, ulipristal acetate, and tamoxifen may all provide temporary relief.

SUMMARY

Women's healthcare providers can offer patients adjunct medical therapies to minimize bothersome bleeding associated with progestin LARC use, which may result in increased satisfaction and continuation rates of these effective forms of contraception.

What is the best drug treatment for premenopausal women with bleeding irregularities using the levonorgestrel-releasing intrauterine system? A systematic review

OBJECTIVE

Up to 60% of women discontinue using the levonorgestrel-releasing intrauterine system (LNG-IUS) within 5 years because of bleeding irregularities, pain and/or systemic progestogenic adverse effects. The aim of the study was to assess treatment options for bleeding irregularities in women using the 52 mg LNG-IUS.

METHODS

Database searches of Medline, Embase/Ovid and the Cochrane Library were carried out, and journals were searched by hand, for relevant studies published from database inception to March 2020. Inclusion criteria were randomised controlled trials (RCTs), prospective cohort studies and case-control studies of premenopausal women using the LNG-IUS and receiving medical treatment for bleeding irregularities. Screening, data extraction and quality assessment of retrieved articles were carried out independently by two pairs of reviewers. The primary outcome was the reduction of bleeding/spotting days.

RESULTS

Of the 3061 studies identified, eight met our inclusion criteria: six RCTs and two prospective cohort studies. The eight studies enrolled a total of 677 women who were treated with tamoxifen, mifepristone, ulipristal acetate, naproxen, oestradiol, mefenamic acid, tranexamic acid or the progesterone receptor modulator CDB 2914. The results of our analysis indicated that naproxen may be effective for the prophylactic treatment of bleeding immediately (<12 weeks) after LNG-IUS insertion (high level of evidence). Oestradiol may be effective in treating ongoing bleeding irregularities >6 months after insertion (low level of evidence).

CONCLUSION

Evidence for the medical treatment of (ongoing) bleeding irregularities during use of the LNG-IUS is lacking and more research is needed on the topic.

Hormonal Profiles of Menstrual Bleeding Patterns During the Luteal-Follicular Transition

CONTEXT

Menstrual cycle function is determined by a complex endocrine axis that controls the ovaries and endometrium. While the late luteal phase is characterized by declining progesterone and estrogen, how these hormonal profiles relate to menstrual bleeding patterns is not well understood.

OBJECTIVE

Characterize associations between luteal phase hormonal profiles and subsequent menstrual bleeding patterns, specifically spotting before bleeding.

DESIGN, SETTING, AND PARTICIPANTS

We examined creatinine-adjusted urinary estrone 3-glucuronide (E13G) and pregnanediol 3-glucuronide (Pd3G) levels in relation to spotting in 116 premenopausal women (ages 20-47) who kept daily menstrual diaries and collected first morning urine samples for ≥ 2 consecutive cycles or 1 luteal-follicular transition (n = 283 transitions). We used linear mixed models to estimate associations between luteal phase hormone levels and spotting before bleeding.

MAIN OUTCOME MEASURE(S) AND RESULTS

Transitions with ≥ 1 days of spotting before menstrual bleeding (n = 118) had greater luteal phase Pd3G levels vs nonspotting transitions (n = 165). Differences in Pd3G between spotting and nonspotting transitions were largest at menses onset (34.8%, 95% confidence interval, 18.9%, 52.7%). Pd3G levels for spotting transitions dropped to similar levels as nonspotting transitions an average of 1 day later, which aligned with the first day of bleeding for transitions with contiguous spotting. Spotting transitions were preceded by slower rates of Pd3G decline than nonspotting transitions, whereas E13G declines were similar.

CONCLUSIONS

Self-reported bleeding patterns may provide insight into luteal phase Pd3G levels. First bleed appears to be the best choice for defining the end of the luteal phase and achieving hormonal consistency across transitions.

Tamoxifen for the prevention of unscheduled bleeding in new users of the levonorgestrel 52-mg intrauterine system: a randomized controlled trial

OBJECTIVE

To determine if a course of oral tamoxifen initiated following placement of a levonorgestrel 52-mg intrauterine system (IUS) reduces bleeding/spotting days over 30 days.

STUDY DESIGN

In this single-center, double-blind, placebo-controlled trial, we recruited women ages 15-45 years initiating the levonorgestrel 52-mg IUS. We randomized eligible women to tamoxifen 10 mg or placebo twice daily for 7 days starting 21 days after levonorgestrel 52-mg IUS insertion. Participants tracked bleeding/spotting days via daily electronic diaries for 30 days after starting drug treatment. We assessed participant satisfaction with their bleeding pattern and the IUS using a visual analog scale (0-100 mm). A sample size of 42 provided 80% power to detect a difference of 7 bleeding/spotting days in 30 days by two-sample t test, accounting for an expected 20% dropout rate.

RESULTS

From September 2016 to January 2018, 42 women enrolled. A total of 34 women provided complete bleeding/spotting data, and 30 women provided satisfaction data. Mean bleeding/spotting days over 30 days did not differ between tamoxifen (12.0±5.8 days) and placebo users (16.8±9.0 days), p=.08. We found no significant differences in mean satisfaction with bleeding profiles (51 mm tamoxifen vs. 59 mm placebo, p=.48) or with the IUS (83 mm vs. 75 mm, p=.36) between groups. Both groups reported similar rates of adverse events, with no serious adverse events reported.

CONCLUSION

A course of oral tamoxifen did not improve early breakthrough bleeding or satisfaction in new users of the levonorgestrel 52-mg IUS.

IMPLICATIONS

Although tamoxifen treatment caused a trend toward modest bleeding/spotting day reduction in new levonorgestrel 52-mg IUS users, bleeding satisfaction did not improve. Future studies of tamoxifen treatment for IUS-related bleeding issues may be best targeted toward users with ongoing bleeding irregularities or lower-dose IUS products which cause more bleeding irregularities.

Reproductive Health: Options, Strategies, and Empowerment of Women

Contraception is paramount to the overall health and longevity of women. Most women in the United States use birth control in their reproductive lifetimes. All options should be available and easily accessible to permit individualization and optimization of chosen methods. Current contraceptive methods available in the United States are reviewed. Emergency contraception, contraception in the postpartum period, and strategies to tailor methods to those affected by partner violence are also addressed. Tables and flow charts help providers and patients compare various contraceptive methods, optimize the start of a method, and identify resources for addressing safety in those with underlying medical conditions.

[Intrauterine contraception: CNGOF Contraception Guidelines]

OBJECTIVE

To provide national clinical guidelines focusing on intrauterine contraception.

METHODS

A systematic review of available literature was performed using Pubmed and Cochrane libraries. American, British and Canadian guidelines were considered as well.

RESULTS

Intrauterine contraception (IUC) displays a wide panel of indications, including adolescents, nulliparous, patients living with HIV before AIDS (Grade B) and women with history of ectopic pregnancy (Grade C). Cervical cancer screening should not be modified in women with IUC (Grade B). Bimanual examination and cervix inspection are mandatory before device insertion (Grade B). Patients should not systematically undergo screening for sexually transmitted infections (STI) before device insertion (Grade B). Screening for STI should be preferably done before insertion but it can be performed at the time of device insertion in asymptomatic women (Grade B). Routine antibiotic prophylaxis and premedication are not recommended before insertion (Grade A). A follow-up visit may be offered several weeks after insertion (Professional consensus). Routine pelvic ultrasound examination in not recommended after device insertion (Grade B). In patients with IUC, unscheduled bleeding, when persistent or associated with pelvic pain, requires further investigation to rule out complication (Professional agreement). Suspected uterine perforation warrants radiological workup to locate the device (Professional consensus). Laparoscopic approach should be preferred for elective removal of intrauterine device from abdominal cavity (Professional consensus). In case of accidental pregnancy with intrauterine device in situ, ectopic pregnancy should be excluded (Grade B). In case of viable and desired intrauterine pregnancy, intrauterine device removal is recommended if the strings are reachable (Grade C). Detection of Actinomyces-like organisms on pap smear in asymptomatic patients with intrauterine contraception does not require further intervention (Grade B). Immediate removal of intrauterine device is not recommended in case of STI or pelvic inflammatory disease (Grade B). Device removal should be considered in the absence of clinical improvement after 48 to 72 hours of appropriate treatment (Grade B).

CONCLUSION

Intrauterine contraception is a long-acting and reversible contraception method displaying great efficacy and high continuation rate. In contrast, complication rate is low. It should thus be offered to both nulliparous and multiparous women.

Unscheduled vaginal bleeding with progestin-only contraceptive use

Nearly 20% of women using contraception are using progestin-only contraception, including progestin-only pills, depot-medroxyprogesterone acetate, subdermal etonogestrel implants, and levonorgestrel intrauterine devices. This number will continue to grow with the increased provision of long-acting reversible contraception. Although overall satisfaction among women using progestin-only contraception is high, dissatisfaction and discontinuation may be associated with unscheduled bleeding and spotting. The exact etiology of irregular bleeding associated with progestin-containing contraceptives is not completely understood, yet several mechanisms have been suggested. Several therapies targeting these mechanisms have been evaluated with mixed results. This paper will review the physiology and management of unscheduled bleeding with progestin-containing contraceptives.

Bridging progestogens in pregnancy and pregnancy prevention

Steroid hormones have been in use for more than a half a century as contraceptive agents, and only now are researchers elucidating the biochemical mechanisms of action and non-target effects. Progesterone and synthetic progestins, critical for women's health in the US and internationally, appear to have important effects on immune functioning and other diverse systems. Apart from the contraceptive world is a separate field that is devoted to understanding progesterone in other contexts. Based on research following a development timeline parallel to hormonal contraception, progesterone and 17-hydroxyprogesterone caproate are now administered to prevent preterm birth in high-risk pregnant women. Preterm birth researchers are similarly working to determine the precise biochemical actions and immunological effects of progesterone. Progesterone research in both areas could benefit from increased collaboration and bringing these two bodies of literature together. Progesterone, through actions on various hormone receptors, has lifelong importance in different organ systems and researchers have much to learn about this molecule from the combination of existing literatures, and from future studies that build on this combined knowledge base.

A randomized controlled trial of daily text messages versus monthly paper diaries to collect bleeding data after intrauterine device insertion

OBJECTIVE

Bleeding data in contraceptive trials are often collected using daily diaries, but data quality may vary due to compliance and recall bias. Text messaging is a widespread and promising modality for data collection.

STUDY DESIGN

This trial randomized participants 1:1 to use text messages or paper diaries to report on bleeding experienced during the 90 days after intrauterine device (IUD) insertion. Participants chose either the copper T380A or the 52-mg levonorgestrel IUD. Our primary outcome was number of days of reported bleeding data. We hypothesized that data gathered with daily text messages would have fewer missing values than paper diaries. Intention to treat analyses used the rank-sum test to compare medians.

RESULTS

Two hundred thirty women enrolled, and randomization yielded groups similar in baseline characteristics. Twenty percent of participants provided no bleeding data; of these, 77% were assigned to paper diaries. With 90 days of reporting, approximately 20% in each group provided complete bleeding data. The text group reported a median of 82 days [interquartile range (IQR) 40-89] and the paper group reported a median of 36 days (IQR 0-88) (p≤.001). The number of responses received decreased gradually over the 90-day period but was always higher in the text group. Women who had attained higher levels of education did well regardless of data collection modality, while response rates of text messages were greater among those with a high school education or less (p<.01).

CONCLUSIONS

Participants reporting bleeding via text messages provided more complete data than women using paper diaries.

IMPLICATIONS

Depending on resources and population of interest, text messages may be a useful modality to improve data collection for patient-reported outcomes.

Characteristics associated with discontinuation of long-acting reversible contraception within the first 6 months of use

OBJECTIVE

To measure discontinuation within 6 months among users of the levonorgestrel intrauterine system, copper intrauterine device (IUD), and etonogestrel implant and identify baseline characteristics associated with early discontinuation.

METHODS

This was an analysis of the Contraceptive CHOICE Project, a cohort study of 9,256 participants provided with no-cost contraception and followed with telephone interviews at 3 and 6 months. We used logistic regression to investigate characteristics associated with early discontinuation of the two IUDs and implant and described reasons for discontinuation.

RESULTS

A total of 6,167 participants were eligible for this analysis. Follow-up data were available for 5,928 participants; 5,495 (93%) were using their method at 6 months and 433 (7%) had discontinued. Discontinuation rates were 7.3%, 8.0%, and 6.9% for the levonorgestrel intrauterine system, copper IUD, and implant, respectively. After adjusting for age, race, marital status, low socioeconomic status, and history of sexually transmitted infection, we found that unmarried women were slightly more likely to discontinue compared with married women (adjusted odds ratio [OR] 1.26, 95% confidence interval [CI] 1.01-1.59 and adjusted OR 1.62, 95% CI 1.11-2.37, respectively). No other baseline characteristics, including younger age (14-19 years), were associated with early discontinuation. The most common reason given for discontinuation was cramping among IUD users and irregular or frequent bleeding among implant users.

CONCLUSION

Rates of discontinuation of long-acting reversible contraception at 6 months is low and not increased in adolescents and young women. Intrauterine devices and the implant should be considered as first-line contraceptive options among all women to reduce unintended pregnancy.

LEVEL OF EVIDENCE

: II.

Treatment of vaginal bleeding irregularities induced by progestin only contraceptives

BACKGROUND

Despite their high effectiveness, progestin-only contraceptives are considered less than ideal by the many women who experience irregular vaginal bleeding when using them. Current treatments to control these bleeding problems are not sufficiently effective.

OBJECTIVES

We evaluated preventive and therapeutic approaches to normalise bleeding irregularities associated with the use of progestin-only contraceptives.

SEARCH METHODS

Literature was identified through database searches, reference lists, organisations and individuals, covering the period until May-June 2012.

SELECTION CRITERIA

Trials with random or systematic allocation, testing interventions for the prevention or treatment of bleeding irregularities associated with the use of progestin-only contraceptives were eligible.

DATA COLLECTION AND ANALYSIS

Results are expressed as relative risks (RR) with 95% confidence interval (CI) for categorical data and as weighted mean difference (WMD) with 95% CI for continuous data. When we encountered heterogeneity (visual or statistical) we used the random-effects model (quantitative) or did not produce a summary estimate (qualitative).

MAIN RESULTS

Thirty-three randomised controlled trials enrolling 3677 participants were included. Two thirds of the trials were determined to reflect low to moderate risk of bias.Estrogen treatments reduced the number of days of an ongoing bleeding episode in DMPA and Norplant users. However, treatment frequently led to more discontinuation due to gastrointestinal upset.Combinations of oral ethinyl estradiol and levonorgestrel improved bleeding patterns in Norplant users, but method discontinuation rates were unchanged. One trial reported successful use of combined oral contraceptives in treating amenorrhea among DMPA users.Norplant users, but not Implanon users, administered the anti-progestin mifepristone reported fewer days of bleeding during treatment than those given placebo. Mifepristone used monthly by new Norplant acceptors reduced bleeding, when compared to placebo.A variety of NSAIDS have been evaluated for their ability to treat abnormal bleeding, with mixed results.Norplant users receiving SERM (tamoxifen) had less unacceptable bleeding after treatment and were more likely to continue using Norplant than those receiving placebo.Tranexamic acid, mifepristone combined with an estrogen and doxycycline were more effective than placebo in terminating an episode of bleeding in women using progestin-only contraceptives, according to three small studies.

AUTHORS' CONCLUSIONS

Some women may benefit from the interventions described, particularly with cessation of current bleeding. Several regimens offer promise in regulating bleeding, but findings need to be reproduced in larger trials. The results of this review do not support routine clinical use of any of the regimens included in the trials, particularly for long-term effect.

Treatment of vaginal bleeding irregularities induced by progestin only contraceptives

BACKGROUND

Despite their high effectiveness, progestin-only contraceptives are considered less than ideal by the many women who experience irregular vaginal bleeding when using them. Current treatments to control these bleeding problems are not sufficiently effective.

OBJECTIVES

We evaluated preventive and therapeutic approaches to normalise bleeding irregularities associated with the use of progestin-only contraceptives.

SEARCH METHODS

Literature was identified through database searches, reference lists, organisations and individuals, covering the period until May-June 2012.

SELECTION CRITERIA

Trials with random or systematic allocation, testing interventions for the prevention or treatment of bleeding irregularities associated with the use of progestin-only contraceptives were eligible.

DATA COLLECTION AND ANALYSIS

Results are expressed as relative risks (RR) with 95% confidence interval (CI) for categorical data and as weighted mean difference (WMD) with 95% CI for continuous data. When we encountered heterogeneity (visual or statistical) we used the random-effects model (quantitative) or did not produce a summary estimate (qualitative).

MAIN RESULTS

Thirty-three randomised controlled trials enrolling 3677 participants were included. Two thirds of the trials were determined to reflect low to moderate risk of bias.Estrogen treatments reduced the number of days of an ongoing bleeding episode in DMPA and Norplant users. However, treatment frequently led to more discontinuation due to gastrointestinal upset.Combinations of oral ethinyl estradiol and levonorgestrel improved bleeding patterns in Norplant users, but method discontinuation rates were unchanged. One trial reported successful use of combined oral contraceptives in treating amenorrhea among DMPA users.Norplant users, but not Implanon users, administered the anti-progestin mifepristone reported fewer days of bleeding during treatment than those given placebo. Mifepristone used monthly by new Norplant acceptors reduced bleeding, when compared to placebo.A variety of NSAIDS have been evaluated for their ability to treat abnormal bleeding, with mixed results.Norplant users receiving SERM (tamoxifen) had less unacceptable bleeding after treatment and were more likely to continue using Norplant than those receiving placebo.Tranexamic acid, mifepristone combined with an estrogen and doxycycline were more effective than placebo in terminating an episode of bleeding in women using progestin-only contraceptives, according to three small studies.

AUTHORS' CONCLUSIONS

Some women may benefit from the interventions described, particularly with cessation of current bleeding. Several regimens offer promise in regulating bleeding, but findings need to be reproduced in larger trials. The results of this review do not support routine clinical use of any of the regimens included in the trials, particularly for long-term effect.

Iatrogenic unscheduled (breakthrough) endometrial bleeding

Erratic, "unscheduled", vaginal bleeding continues to be the greatest disadvantage associated with widespread use of long-acting, progestogen-only methods of contraception. As a consequence, it is also the main reason for premature discontinuation of use of these methods in most cultures. From other perspectives, these methods have high acceptability, very high contraceptive efficacy and a range of valuable, added, non-contraceptive health benefits. There has been widespread awareness of the variability of these vaginal bleeding patterns associated with long-acting methods for several decades and much research has been invested into studying their patterns and implications. Considerable research has also been directed towards trying to understand the underlying mechanisms responsible for the unpredictable bleeding. Much has been clarified about the multiple mechanisms contributing to the appearance of superficial, thin-walled fragile vessels within the endometrium of many of those women with troublesome bleeding, but there is still little understanding of why some women develop these vessels and others have no fragile vessels (and may therefore develop amenorrhea). We now have several medical approaches to reliably stopping a prolonged episode of troublesome bleeding, but no good therapy to produce long-lasting relief from recurrence of erratic bleeding in predisposed women. Future understanding of the variability in individual endometrial responses in different women may be a key to solving this frustrating symptom.