Determinants of menstrual bleeding patterns among women using natural and hormonal methods of contraception. I. Regional variations

Can initial vaginal bleeding patterns in etonogestrel implant users predict subsequent bleeding in the first 2 years of use?

OBJECTIVES

To evaluate if a simple method for characterizing vaginal bleeding patterns in etonogestrel contraceptive implant users can predict subsequent patterns and bleeding-related discontinuation over the first 2 years of use.

STUDY DESIGN

We reanalyzed phase 3 study bleeding data for non-breastfeeding participants from the United States, Europe, Russia and Chile during the first 2 years of implant use to characterize and correlate bleeding patterns. We used 90-day reference periods with period 1.1 starting at Day 29 and ending at Day 118. We dichotomized bleeding patterns as "favorable" (amenorrhea, infrequent bleeding and normal frequency bleeding without prolonged bleeding) or "unfavorable' (prolonged and/or frequent bleeding) and tracked user groups based on these bleeding patterns in reference period 1.1 through Year 1 and from Year 1 through Year 2, respectively.

RESULTS

We evaluated data from 537 and 428 women with up to 1 and 2 years use, respectively. Of the 325 (60.5%) women with favorable bleeding in reference period 1.1, 275 (84.6%) reported favorable bleeding also in reference period 2, 197 (60.6%) reported favorable bleeding throughout Year 1, and favorable bleeding in 75-85% of reference periods in Year 2. Among 212 (39.5%) women with unfavorable bleeding in reference period 1.1, 118 (55.7%) continued with unfavorable bleeding in reference period 2, while about 40%-50% reported favorable patterns in RP 2, 3 and/or 4. Initial favorable bleeding resulted in lower discontinuation rates than initial unfavorable bleeding in years 1 (3.7% vs 12.7%, p≪.0001) and 2 (2.5% vs 16.5%, p≪.0001).

CONCLUSION

Implant users with favorable bleeding in the first reference period are likely to continue with favorable bleeding over the next 2 years. Initial bleeding patterns predict overall continuation rates in years 1 and 2. Implications Statement When evaluating vaginal bleeding in any 90-day reference period over 2 years of etonogestrel implant use, approximately 80% of women with favorable and 40% with unfavorable bleeding patterns will have favorable bleeding in the next reference periods. These findings can facilitate counseling regarding bleeding for women using the etonogestrel implant.

Bleeding patterns during the menopausal transition in the multi-ethnic Study of Women's Health Across the Nation (SWAN): a prospective cohort study

OBJECTIVE

Previous studies describing menses duration and heaviness of flow during the menopausal transition (MT) have been short in duration and limited to white women. We estimated the frequency of and risk factors for prolonged bleeding, spotting and heavy bleeding during the MT in an ethnically diverse population.

DESIGN

Prospective community-based cohort study.

SETTING USA

southeastern Michigan, northern California and Los Angeles, California.

POPULATION

A total of 1320 midlife women who participated in the Study of Women's Health Across the Nation (SWAN) Menstrual Calendar Substudy. Participants included African-American, white, Chinese, and Japanese women.

METHODS

Women completed daily menstrual calendars from 1996 to 2006, and provided information on hormone therapy, smoking and physical activity. Annual measures included height and weight. Kaplan-Meier survival analysis and multivariable regression were used to analyse the data.

MAIN OUTCOME MEASURES

Menses of 10+ days, spotting of 6+ days, heavy bleeding of 3+ days.

RESULTS

At least three occurrences of menses 10+ days was reported by 77.7% (95% confidence interval [95% CI] 56.7-93.2), of 6+ days of spotting by 66.8% (95% CI 55.2-78.0) and of 3+ days of heavy bleeding by 34.5% (95% CI 30.2-39.2) of women. Menses of 10+ days, 6+ days of spotting, and 3+ days of heavy bleeding were associated with MT stage, uterine fibroids, hormone use and ethnicity. Body mass index was associated with 3+ days of heavy bleeding.

CONCLUSIONS

These data provide clinicians and women with important information about the expected frequency of prolonged and heavy bleeding and spotting during the menopausal transition that may facilitate clinical decision making.

Darwin's legacy: an evolutionary view of women's reproductive and sexual functioning

On the Origin of species, published just over 150 years ago, has deeply influenced thinking in both scientific and wider communities. Darwin's legacy includes recognition of the fact that all organisms evolve; that variation within and between species is natural and normal; and that an evolutionary approach to understanding the sources and consequences of this variation comprises theoretical frameworks, testable hypotheses, and rigorously collected evidence. With an eye toward facilitating communication and productive collaboration among researchers from different intellectual traditions who nonetheless share a common interest in women's reproductive and sexual functioning, we discuss evolutionary concepts and models, summarize the known variability in ovarian functioning and consider the implications of this variability for conducting sex research, and evaluate the relative merits of various biomarkers that serve as proxy measurements of a woman's reproductive and hormonal status. With these perspectives and methods from reproductive ecology at hand, we examine several contentious issues: the links between hormones and sexuality in premenopausal and perimenopausal women, the causes of premenstrual syndrome, and the existence (or not) of menstrual synchrony. In none of these cases is as much known as is often claimed. In each, there are abundant opportunities for innovative, albeit challenging, research.

Menstrual pattern changes from levonorgestrel subdermal implants and DMPA: systematic review and evidence-based comparisons

BACKGROUND

Many women want a lengthy duration of contraception but are wary of the menstrual changes from depot medroxyprogesterone acetate (DMPA). A subdermal levonorgestrel (LNG) implant may be a reasonable alternative. However, information on menstrual changes from these methods has not been summarized and compared in an easy-to-understand form.

STUDY DESIGN

We systematically reviewed the published literature on these contraceptives to find research that used menstrual diaries and standard World Health Organization definitions. We attempted to find information on amenorrhea, number of bleeding or spotting episodes, number of bleeding or spotting days and normal patterns, as reported in four consecutive 90-day reference periods.

RESULTS

We found 16 published articles meeting our criteria and involving diaries of up to 1600 DMPA users and 2300 LNG implant users. We were able to compare the two methods on only three outcomes. For DMPA use, the weighted prevalence of amenorrhea at successive 90-day periods was 12%, 25%, 37% and 46%. The comparable estimates for the LNG implant were 11%, 13%, 9% and 13%. Levonorgestrel implant users experienced a higher average number of bleeding or spotting days compared to DMPA users, but this average was similar to what is expected naturally. At 12 months, normal menstrual patterns were experienced by 23% of LNG implant users compared to 11% of DMPA users.

CONCLUSIONS

Like most hormonal contraception, LNG implants usually produce menstrual changes; however, the changes do not appear to deviate from normal patterns as much as the changes from DMPA. Understanding these differences and other method attributes might help women make an informed choice about which contraceptive to use.

Bleeding patterns associated with oral contraceptive use: a review of the literature

The regulation of vaginal bleeding is an important effect impacting the choice of contraceptive methods. However, comparing vaginal bleeding control and disturbance between various contraceptive studies is often limited by the lack of uniformity in the analysis and reporting of the bleeding patterns. In 1986, the World Health Organization (WHO) issued recommendations for the standardized collection, analysis and reporting of bleeding associated with contraceptives based on 90-day reference periods. We systematically reviewed MEDLINE and EMBASE for all articles reporting bleeding data by reference periods in healthy women using oral contraception. Overall, 17 publications between 1986 and September 2006 were included for review. There was marked variability in the reporting of bleeding data with most studies reporting a few selected bleeding parameters. However, these studies showed, in general, that oral contraceptive users have the greatest bleeding (i.e., results in the highest number of bleeding/spotting days) during the first reference period which decreases by Reference Period 4. Reporting of the bleeding/spotting data using the WHO recommendations may be useful in objectively comparing vaginal bleeding patterns among different oral contraceptive products.

Endometrial histology of Depomedroxyprogesterone acetate users: a pilot study

Objective. To obtain pilot data on the endometrial histology of Depomedroxyprogesterone acetate (Depo-Provera, DMPA) users experiencing breakthrough bleeding (BTB) versus users with amenorrhea. To compare the endometrial histology of patients who used DMPA continuously for 3–12 months versus those who used it for 13 months or more. Methods. Cross-sectional study. Endometrial biopsy was obtained fromall consenting patients who used DMPA for at least 3 months. Patients were divided into those with BTB in the last 3 months versus those with amenorrhea for at least 3 months. Histology results and duration of therapy were compared. Results. The proportion of women with chronic endometritis, uterine polyps, atrophic, proliferative, or progesteronedominant endometrium did not differ between those DMPA users with BTB versus those with amenorrhea. Duration of therapy did not correlate with symptoms of BTB or endometrial histology. Chronic endometritis was the most common histologic finding (10/40, 25%) and occurred more often in women experiencing BTB (35% versus 15%) (RR 1.62 CI 0.91–2.87). Moreover, 45% of women with BTB had received DMPA for more than 12 months. Conclusions. BTB was more common than previously reported in women using DMPA for more than 12 months. Chronic endometritis, which may indicate an underlying infectious or intracavitary anatomic etiology, has not been previously reported as a frequent finding in DMPA users, and may be related to ethnic or other sociodemographic characteristics of our patient population. Further study to elucidate the etiology of chronic endometritis in these patients is warranted.

Presence or absence of menstruation in young girls

Menstruation is a periodic discharge of sanguinous fluid and sloughing of the uterine lining in the female. It is an event characteristic of the reproductive cycle in humans and most subhuman primates and has no known biological function. However, it is an integral part of a woman's experience throughout her reproductive life. This article will examine menstrual patterns and concerns in young girls. The section on absent menstruation will concentrate on premature ovarian failure.

Combined hormonal contraceptive trials: variable data collection and bleeding assessment methodologies influence study outcomes and physician perception

Initially approved for use in the United States nearly 50 years ago, oral hormonal contraceptives containing both estrogen and progestin have undergone steady improvements in safety and convenience. Concurrent with improvements in safety associated with decreasing doses of both steroids, there has been an increased incidence of unscheduled bleeding and spotting. There exist no standards regarding data collection techniques and methods, and reporting and analysis of bleeding and spotting events during combined hormonal contraceptive (CHC) trials. For the regulatory review of hormonal contraceptives, data regarding the incidence of bleeding and spotting events are not included in either of the traditional categories of efficacy and safety. Standardization of methods for collecting and analyzing data about cycle control in all clinical trials of CHCs is long overdue. Until such standards are developed and implemented, clinicians need to familiarize themselves with the techniques used in each study in order to provide correct information to their patients about the frequency of bleeding and spotting associated with different formulations and delivery systems.

Role of progestins in contraception

Progestins have been used for contraception for more than 30 years. The main goal was to develop a contraceptive method devoid of the metabolic or clinical side-effects associated with the use of estrogens. The development of new contraceptive methods and formulations is time-consuming and requires devotion, belief, and also strong economical basis. As a result of this endeavor new methods have been developed: oral progestins, implants, injectables, intrauterine hormonal systems, and vaginal rings. Progestin-only contraceptives may be preferable in some situations, which have absolute or relative contraindications to estrogen, side-effects to estrogen containing hormonal contraception, lactation, and comfort and feasibility of formulations for long-term use. At present, emergency contraception is also performed with progestin.

Vaginal bleeding patterns among rural highland Bolivian women: relationship to fecundity and fetal loss

Among the most common reasons given for discontinued use of some contraceptive methods is a disturbance in the menstrual cycle, particularly changes in vaginal bleeding. Work to date suggests marked populational variation in menses duration, but few data have been collected from South America. This longitudinal study of non-contracepting Aymara women (n = 189 providing 837 non-truncated bleeding episodes) identified conceptions and fetal loss via urine tests for human chorionic gonadotropin and classified episodes accordingly to test the hypotheses that (a) vaginal bleeding patterns differ between lactating and non-lactating women, (b) duration of vaginal bleeding accompanying fetal loss differs from that of menstruation, (c) menses preceding a conception are longer than those not followed by a conception. Compared to published values, mean menses duration (3.5 days) in these women was relatively short. Menses duration was not significantly correlated with current age, age at menarche or first birth, parity, time postpartum, or menstrual segment length. Mean menses duration (not preceding a conception) was comparable for lactating and non-lactating women. Mean duration of fetal loss bleeding did not differ from that of menses. Pre-conception episodes were significantly longer than those not followed by conception. Thus, because the rate of conceptions was twice as great among lactating than non-lactating women, the mean duration of all menses (irrespective of conception) was significantly longer in lactating women. Bolivian, and perhaps other South American, women may be particularly disinclined to accept contraceptives (e.g., intrauterine devices) that modify an otherwise relatively brief menses duration. Therefore, a wide variety of contraceptive choices accompanied by population-specific informed counseling is essential. In addition, these findings suggest that studies of fecundability limited to non-lactating women may be biased toward those of relatively lower fecundity and that menses duration may be predictive of risk for some cancers.

Menstrual disorders and occupational, stress, and racial factors among military personnel

Few studies have assessed multiple stress factors as a potential risk for menstrual disorders. This study evaluated whether work-related stress or life event stress was associated with alterations in menstrual function of military personnel. The study is unique in that it evaluated the association between race and three job factors--job stress, handling chemical mixtures, and being a military or civilian employee of the US Air Force. A comprehensive questionnaire was administered to 170 healthy, premenopausal employed women to examine the relationship between work-related or life event stress and menstrual disorders. Multiple logistic regression analyses showed no statistically significant association between work-related stress and menstrual disorders, whereas life event stress was significantly associated with dysmenorrhea (odds ratio [OR], 2.20; 95% confidence interval [CI], 1.08 to 4.50) abnormal cycle length (OR, 3.42; CI, 1.12 to 10.50), and hypermenorrhea (OR, 2.99; 95% CI, 1.20 to 7.42). Having one or more menstrual disorders was significantly associated with life events by race interaction (OR, 6.52; 95% CI, 2.45 to 17.36). Non-Caucasians had significantly increased risks of hypermenorrhea (OR, 4.99; 95% CI, 2.07 to 12.05) and abnormal cycle length (OR, 4.12; 95% CI, 1.47 to 11.55). The prevalence of menstrual disorders in this military population was 31.2% for dysmenorrhea, 17.9% for hypermenorrhea, and 12.0% for abnormal cycle length. This study suggests that women in the military report less day-to-day job stress but more atypical life events, including those related to their jobs, and that these life events are associated with adverse menstrual consequences.

An integrated analysis of vaginal bleeding patterns in clinical trials of Implanon

The vaginal bleeding patterns observed during the use of the single-rod progestin-only implant, Implanon, compared with those seen during the use of the six-capsule implant, Norplant, have been analyzed. The acceptability of these bleeding patterns was also assessed. An integrated analysis of 13 different trials was done, studying reference periods (RP) of 90 days. These trials included totals of 1716 Implanon users and 689 Norplant users. There were statistically significant lower mean values over RP 2-8 the range over RP 2-8 is presented) for Implanon, for the number of bleeding-spotting days (15.9-19.3 vs 19.4-21.6; p = 0.0169), the number of bleeding days (7.5-10.0 vs. 11.7-13.1; p < 0.001), and the number of bleeding-spotting episodes (2.2-2.7 vs. 3.1-3.3; p < 0.0001). The bleeding patterns of Implanon users appeared to be more variable than those observed with Norplant: Implanon users had more amenorrhea, and slightly more infrequent bleeding, frequent bleeding, and prolonged bleeding than Norplant users. The difference was only statistically significant for amenorrhea (17.9%-24.8% with Implanon compared with 2.0%-7.0% for Norplant over RP 2-8). There were no statistically significant differences in the acceptability of the two products as indicated by the discontinuation rates, which were 30.2% and 0.9% in Europe and Southeast Asia, respectively, for Implanon, and 22.5% and 1.4%, respectively, in the two regions, for Norplant. The individual bleeding pattern was not predictable. However, in general, it can be stated that women initially without bleeding or with infrequent bleeding have only a small chance of becoming frequent bleeders, and vice versa. Dysmenorrhea clearly improved during use of both Implanon and Norplant. Neither Implanon nor Norplant caused anemia.

The comparative trial of TCu 380A IUD and progesterone-releasing vaginal ring used by lactating women

The objective of this paper was to compare the efficacy, acceptability, safety, and bleeding pattern of TCu 380A intrauterine device (IUD) and progesterone-releasing vaginal ring used by breastfeeding women. The study population included 97 breastfeeding women using IUD and 100 women using vaginal ring. Of the IUD users, no insertion failure, perforation, or accidental pregnancy occurred in 12 months. There was one IUD expulsion. There were no discontinuations of IUD due to medical reasons other than expulsion. The total discontinuation rate was 2.3%. In the ring group, no accidental pregnancy occurred. The major reasons for discontinuation were ring use-related problems and vaginal problems. The total discontinuation rate was 65.4% within 1 year. The frequency of any one complaint among the ring users was higher than that among the IUD users. There were no differences in the proportion of women having no sexual activity and in the weight of their babies between the two groups. Compared with the IUD users, the median number of bleeding/spotting (B/S) episodes and B/S days of the vaginal ring users were fewer; consequently, the mean length of B/S-free interval was longer in all four reference periods; the mean length of B/S episode and segment were the same; the occurrence of amenorrhea was more frequent; in contrast, the proportions of normal bleeding patterns were fewer. The frequencies of prolonged bleeding, frequent bleeding, and infrequent bleeding patterns did not differ between the two groups. The percentage of irregular bleeding was fewer only in the first two reference periods. It is concluded that the TCu 380A IUD and progesterone-releasing vaginal ring used by breastfeeding women are safe and effective. The higher discontinuation rate of the ring users was mainly because of use-related problems. Breastfeeding women with TCu 380A IUD had better tolerance and acceptability. The TCu 380A IUD does not, but the progesterone-releasing vaginal ring does, suppress the recovery of ovarian function. However, once return of menstruation occurred, there were no differences in bleeding patterns between the two contraceptive methods.

Menstrual bleeding patterns in untreated women. Task Force on Long-Acting Systemic Agents for Fertility Regulation

Menstrual histories recorded by more than 1000 healthy, untreated women have been analyzed using the reference period method. Results were obtained for each year of age from 15 to 49. Between menarche and age 19, the most important feature of menstrual patterns is their variability. Within-woman mean segment (cycle) length then decreases slowly but steadily, from 29.0 days at age 20 to 26. 7 days at age 40. The range of segment lengths over a year also falls, to a minimum of 7 days at age 38. During the 40s, mean segment length rises to 29 days at age 49, and there is a sharp increase in the range, to 28 days. The length and variability of bleeding episodes, however, changes little between the ages of 19 and 49. Modifications to the World Health Organization definitions of 'clinically important' bleeding patterns are proposed.

A multicentred phase III comparative clinical trial of Mesigyna, Cyclofem and Injectable No. 1 given by intramuscular injection to Chinese women. II. The comparison of bleeding patterns

Between 1988 and 1992, a randomized phase III clinical trial was conducted in China to compare three monthly injectable contraceptives: Mesigyna, Cyclofem and Injectable No. 1. This paper presents a detailed analysis of the menstrual diaries provided by 5098 (89%) of the subjects. In total, 902, 903 and 913 diaries were analyzed to compare bleeding patterns induced by Mesigyna, Cyclofem and Injectable No. 1. The first withdrawal bleeding usually occurs 14-20 days after the first injection for all three of these preparations. Thereafter, 50% of Mesigyna users had precisely 3 bleeding/spotting episodes every 90 days, 50% of Cyclofem users had 2-3 and 50% of Injectable No. 1 users had 3-4 episodes every 90 days. Relative to users of Mesigyna or Cyclofem, Injectable No. 1 users had 2-3 more bleeding/spotting days, and a shorter length of bleeding/spotting-free intervals in each period. 63.7%, 41.4% and 60.6% of subjects using Mesigyna, Cyclofem and Injectable No. 1, respectively, had bleeding patterns similar to their untreated patterns in the first 90-day period. The percentages increased to 82.2% 67.8% and 75.0% in the fourth 90-day period. A total of 1815 diaries for Mesigyna and 1802 for Cyclofem were analyzed for more in depth comparison of these two methods. The number of bleeding/spotting days over four periods showed little difference between the two group, but there were more spotting days and there was greater individual variability among Cyclofem users.(ABSTRACT TRUNCATED AT 250 WORDS)

Serum norethindrone levels and menstrual pattern after the use of norethindrone implants in rhesus monkeys

Subdermal Silastic implants releasing norethindrone (NET) were inserted in five rhesus monkeys for a period of seven months. The total length of the implants used was 160 mm (eight implants of 20 mm each) containing 160 mg of NET (1 mg NET/mm). The in vivo release rate of NET from the Silastic implants containing 160 mg NET was 3.12 micrograms/day/mm. Menstrual bleeding records were maintained and serum NET levels were estimated from blood samples collected during the period implants remained in situ. There was an initial rise in NET levels, followed by fluctuating levels of NET in three out of five monkeys. The menstrual cycle or bleeding episodes showed a pattern commensurate with the circulating NET levels. None of the monkeys showed intermenstrual bleeding during the treatment period. High levels of NET seem advantageous for an undisturbed menstrual cycle.

Bioavailability of norethindrone and menstrual pattern after insertion of norethindrone acetate implants in rhesus monkeys

Subdermal silastic implants releasing norethindrone acetate were inserted in five rhesus monkeys for a period of seven months. The serum norethindrone (NET) levels were estimated from blood samples collected fortnightly. There was an initial high level of NET followed by fluctuating levels of NET in 4 out of five monkeys. The serum NET values showed individual variation between time periods as well as between monkeys. The analysis of menstrual cycles showed initial amenorrhoea up to day 120-140 in four out of five monkeys. Only one monkey showed vaginal bleeding pattern comparable to normal menstrual cycles; this monkey had serum NET levels less than 10 ng/ml. The pharmacokinetic and pharmacodynamic parameters were similar to those reported in the human female.

The description of menstrual bleeding patterns: towards fewer measures

The disturbance in menstrual bleeding induced by many methods of contraception is an important factor in their acceptability, and women participating in clinical trials of new methods are usually asked to keep a calendar record of the occurrence of bleeding. A recent WHO report recommends that, for analysis and presentation, each menstrual diary should be divided into successive periods, and the woman's bleeding pattern in each period summarized in ten indices. These indices are simple to calculate and easily understood by clinicians, but comparison of several groups is problematic because of the large number of summary statistics generated. Principal components analysis was therefore used to determine whether the indices could be reduced to a smaller number of measures. The analyses showed that three of the indices--the range and maximum value of bleeding/spotting episode lengths and the minimum bleeding-free interval--rarely measure their intended dimension of the bleeding pattern. Most of the essential information about a woman's bleeding pattern is contained in only four of the ten indices: the number of bleeding/spotting episodes, the mean lengths of episodes and intervals, and the range of bleeding-free interval lengths. Together, these indices describe the most important dimensions of a pattern: the amount, frequency and variability of the bleeding.

The efficacy and acceptability of a low-dose levonorgestrel intravaginal ring for contraception in a UK cohort

The efficacy and acceptability of a levonorgestrel-releasing intravaginal ring (IVR) for contraception was assessed in a British cohort studied as part of a multicentre, multinational clinical trial performed under the auspices of the World Health Organisation. One-hundred-and-fifty women took part in the study in two UK centres and completed 1417.5 months of method use. Fifty-nine women discontinued use of the IVR before the end of one year giving an overall discontinuation rate of 39.9 per 100 woman-years. The discontinuation for pregnancy with the ring in situ, was 3.0 per 100 woman-years (life table analysis). Menstrual disturbance, vaginal problems and involuntary expulsion resulted in discontinuation rates of 8.9, 8.4 and 1.6 per 100 woman-years, respectively. This method is an acceptable and effective method of contraception for women.