A randomized, double-blind, placebo-controlled comparison of the impact of low-dose and triphasic oral contraceptives on follicular development

The 7-day contraceptive hormone-free interval should be consigned to history

AIM

This review summarises the available data on the disadvantages of the 7-day contraceptive-free interval (CFI) of combined oral contraceptives (COCs), in contrast to shorter CFIs or continuous use - including flexible regimens - and provides recommendations for practice.

METHODS

Relevant papers were identified by Medline and PubMed. The final reference list was generated on the basis of relevance to the review, with priority given to systematic reviews and randomised controlled trials.

RESULTS

There is considerable inter- and intra-individual variation in the absorption and metabolism of COCs. Even with perfect use, the loss of endocrine suppression during the standard 7-day CFI allows follicular development with the risk of escape ovulation in a vulnerable minority. This risk increases in typical users whenever the CFI is prolonged: late restarts are a common reason for pill omissions. Shortening or eliminating the CFI improves contraceptive efficacy using the lowest doses available, without evidence to date of compromised safety.

CONCLUSIONS

There is no scientific evidence to support a 7-day CFI and it should be replaced either by a continuous flexible regimen, or extended regimens with a shortened CFI, prescribed first-line. In women preferring a monthly 'bleed', a 4-day CFI similarly provides a greater safety margin when pills are omitted.

Oral contraceptive use and mortality after 36 years of follow-up in the Nurses' Health Study: prospective cohort study

OBJECTIVE

To determine whether use of oral contraceptives is associated with all cause and cause specific mortality.

DESIGN

Prospective cohort study.

SETTING

Nurses' Health Study, data collected between 1976 and 2012.

POPULATION

121,701 participants were prospectively followed for 36 years; lifetime oral contraceptive use was recorded biennially from 1976 to 1982.

MAIN OUTCOME MEASURES

Overall and cause specific mortality, assessed throughout follow-up until 2012. Cox proportional hazards models were used to calculate the relative risks of all cause and cause specific mortality associated with use of oral contraceptives.

RESULTS

In our population of 121,577 women with information on oral contraceptive use, 63,626 were never users (52%) and 57,951 were ever users (48%). After 3.6 million person years, we recorded 31,286 deaths. No association was observed between ever use of oral contraceptives and all cause mortality. However, violent or accidental deaths were more common among ever users (hazard ratio 1.20, 95% confidence interval 1.04 to 1.37). Longer duration of use was more strongly associated with certain causes of death, including premature mortality due to breast cancer (test for trend P<0.0001) and decreased mortality rates of ovarian cancer (P=0.002). Longer time since last use was also associated with certain outcomes, including a positive association with violent or accidental deaths (P=0.005).

CONCLUSIONS

All cause mortality did not differ significantly between women who had ever used oral contraceptives and never users. Oral contraceptive use was associated with certain causes of death, including increased rates of violent or accidental death and deaths due to breast cancer, whereas deaths due to ovarian cancer were less common among women who used oral contraceptives. These results pertain to earlier oral contraceptive formulations with higher hormone doses rather than the now more commonly used third and fourth generation formulations with lower estrogen doses.

Oral contraceptives for functional ovarian cysts

BACKGROUND

Functional ovarian cysts are a common gynecological problem among women of reproductive age worldwide. When large, persistent, or painful, these cysts may require operations, sometimes resulting in removal of the ovary. Since early oral contraceptives were associated with a reduced incidence of functional ovarian cysts, many clinicians inferred that birth control pills could be used to treat cysts as well. This became a common clinical practice in the early 1970s.

OBJECTIVES

This review examined all randomized controlled trials that studied oral contraceptives as therapy for functional ovarian cysts.

SEARCH METHODS

In March 2014, we searched the databases of CENTRAL, PubMed, EMBASE, and POPLINE, as well as clinical trials databases (ClinicalTrials.gov and ICTRP). We also examined the reference lists of articles. For the initial review, we wrote to authors of identified trials to seek articles we had missed.

SELECTION CRITERIA

We included randomized controlled trials in any language that included oral contraceptives used for treatment and not prevention of functional ovarian cysts. Criteria for diagnosis of cysts were those used by authors of trials.

DATA COLLECTION AND ANALYSIS

Two authors independently abstracted data from the articles. One entered the data into RevMan and a second verified accuracy of data entry. For dichotomous outcomes, we computed the Mantel-Haenszel odds ratio with 95% confidence interval (CI). For continuous outcomes, we calculated the mean difference with 95% CI.

MAIN RESULTS

We identified eight randomized controlled trials from four countries; the studies included a total of 686 women. Treatment with combined oral contraceptives did not hasten resolution of functional ovarian cysts in any trial. This held true for cysts that occurred spontaneously as well as those that developed after ovulation induction. Most cysts resolved without treatment within a few cycles; persistent cysts tended to be pathological (e.g., endometrioma or para-ovarian cyst) and not physiological.

AUTHORS' CONCLUSIONS

Although widely used for treating functional ovarian cysts, combined oral contraceptives appear to be of no benefit. Watchful waiting for two or three cycles is appropriate. Should cysts persist, surgical management is often indicated.

The state of hormonal contraception today: established and emerging noncontraceptive health benefits

In the 50 years since the advent of combined oral contraceptives the amount of estrogen in oral contraceptives dropped from over 100 mcg to less than 30 mcg. Many noncontraceptive health benefits have emerged that decrease mortality and improve quality of life. Some of the immediate benefits include improvement of menorrhagia and dysmenorrhea, reduction in premenstrual dysphoric disorder symptoms, and decreased acne. As an effective birth control method oral contraceptives also decrease pregnancy-related deaths by preventing pregnancy. After the reproductive years, previous use of oral contraceptives continues to be beneficial, reducing the risk of death from ovarian and endometrial cancer. All these benefits have held up over time whereas cardiovascular risks have lessened because of the decrease in oral contraceptive pill dosage. Decreased ovarian cyst formation is an example of benefit with higher-dose oral contraceptive formulations that no longer holds true with low-dose pills.

Oral contraceptives for functional ovarian cysts

BACKGROUND

Functional ovarian cysts are a common gynecological problem among women of reproductive age worldwide. When large, persistent, or painful, these cysts may require operations, sometimes resulting in removal of the ovary. Since early oral contraceptives were associated with a reduced incidence of functional ovarian cysts, many clinicians inferred that birth control pills could be used to treat cysts as well. This became a common clinical practice in the early 1970s.

OBJECTIVES

This review examined all randomized controlled trials that studied oral contraceptives as therapy for functional ovarian cysts.

SEARCH STRATEGY

We searched the databases of CENTRAL, MEDLINE, POPLINE, and EMBASE, as well as clinical trials databases (ClinicalTrials.gov and ICTRP). We also examined the reference lists of articles and wrote to authors of identified trials to seek articles we had missed.

SELECTION CRITERIA

We included randomized controlled trials in any language that included oral contraceptives used for treatment and not prevention of functional ovarian cysts. Criteria for diagnosis of cysts were those used by authors of trials.

DATA COLLECTION AND ANALYSIS

Two authors independently abstracted data from the articles. One entered the data into RevMan and a second verified accuracy of data entry. For dichotomous outcomes, we computed the Mantel-Haenszel odds ratio with 95% confidence interval (CI). For continuous outcomes, we calculated the mean difference with 95% CI.

MAIN RESULTS

We identified eight randomized controlled trials from four countries; the studies included a total of 686 women. Treatment with combined oral contraceptives did not hasten resolution of functional ovarian cysts in any trial. This held true for cysts that occurred spontaneously as well as those that developed after ovulation induction. Most cysts resolved without treatment within a few cycles; persistent cysts tended to be pathological (e.g., endometrioma or para-ovarian cyst) and not physiological.

AUTHORS' CONCLUSIONS

Although widely used for treating functional ovarian cysts, combined oral contraceptives appear to be of no benefit. Watchful waiting for two or three cycles is appropriate. Should cysts persist, surgical management is often indicated.

Oral contraceptives for functional ovarian cysts

BACKGROUND

Functional ovarian cysts are a common gynecological problem among women of reproductive age worldwide. When large, persistent, or painful, these cysts may require operations, sometimes resulting in removal of the ovary. Since early oral contraceptives were associated with a reduced incidence of functional ovarian cysts, many clinicians inferred that birth control pills could be used to treat cysts as well. This became a common clinical practice in the early 1970s.

OBJECTIVES

This review examined all randomized controlled trials that studied oral contraceptives as therapy for functional ovarian cysts.

SEARCH STRATEGY

We searched the databases of CENTRAL, MEDLINE, POPLINE, and EMBASE, as well as clinical trials databases (ClinicalTrials.gov and ICTRP). We also examined the reference lists of articles and wrote to authors of identified trials to seek articles we had missed.

SELECTION CRITERIA

We included randomized controlled trials in any language that included oral contraceptives used for treatment and not prevention of functional ovarian cysts. Criteria for diagnosis of cysts were those used by authors of trials.

DATA COLLECTION AND ANALYSIS

Two authors independently abstracted data from the articles. One entered the data into RevMan and a second verified accuracy of data entry. For dichotomous outcomes, we used Peto odds ratios with 95% confidence intervals (CI). For continuous outcomes, we calculated mean differences with 95% CI.

MAIN RESULTS

We identified seven randomized controlled trials from four countries; the studies included a total of 500 women. Treatment with combined oral contraceptives did not hasten resolution of functional ovarian cysts in any trial. This held true for cysts that occurred spontaneously as well as those that developed after ovulation induction. Most cysts resolved without treatment within a few cycles; persistent cysts tended to be pathological (e.g., endometrioma or para-ovarian cyst) and not physiological.

AUTHORS' CONCLUSIONS

Although widely used for treating functional ovarian cysts, combined oral contraceptives appear to be of no benefit. Watchful waiting for two or three cycles is appropriate. Should cysts persist, surgical management is often indicated.

Missed hormonal contraceptives: new recommendations

OBJECTIVE

To provide evidence-based guidance for women and their health care providers on the management of missed or delayed hormonal contraceptive doses in order to prevent unintended pregnancy.

EVIDENCE

Medline, PubMed, and the Cochrane Database were searched for articles published in English, from 1974 to 2007, about hormonal contraceptive methods that are available in Canada and that may be missed or delayed. Relevant publications and position papers from appropriate reproductive health and family planning organizations were also reviewed. The quality of evidence is rated using the criteria developed by the Canadian Task Force on Preventive Health Care.

BENEFITS, HARMS, AND COSTS

This committee opinion will help health care providers offer clear information to women who have not been adherent in using hormonal contraception with the purpose of preventing unintended pregnancy.

SPONSORS

The Society of Obstetricians and Gynaecologists of Canada. SUMMARY STATEMENTS: 1. Instructions for what women should do when they miss hormonal contraception have been complex and women do not understand them correctly. (I) 2. The highest risk of ovulation occurs when the hormone-free interval is prolonged for more than seven days, either by delaying the start of combined hormonal contraceptives or by missing active hormone doses during the first or third weeks of combined oral contraceptives. (II) Ovulation rarely occurs after seven consecutive days of combined oral contraceptive use. (II) RECOMMENDATIONS: 1. Health care providers should give clear, simple instructions, both written and oral, on missed hormonal contraceptive pills as part of contraceptive counselling. (III-A) 2. Health care providers should provide women with telephone/electronic resources for reference in the event of missed or delayed hormonal contraceptives. (III-A) 3. In order to avoid an increased risk of unintended pregnancy, the hormone-free interval should not exceed seven days in combined hormonal contraceptive users. (II-A) 4. Back-up contraception should be used after one missed dose in the first week of hormones until seven consecutive days of correct hormone use are established. In the case of missed combined hormonal contraceptives in the second or third week of hormones, the hormone-free interval should be eliminated for that cycle. (III-A) 5. Emergency contraception and back-up contraception may be required in some instances of missed hormonal contraceptives, in particular when the hormone-free interval has been extended for more than seven days. (III-A) 6. Back-up contraception should be used when three or more consecutive doses/days of combined hormonal contraceptives are missed in the second and third week until seven consecutive days of correct hormone use are established. For practical reasons, the scheduled hormone-free interval should be eliminated in these cases. (II-A) 7. Emergency contraception is rarely indicated for missed combined hormonal contraceptives in the second or third week of the cycle unless there are repeated omissions or failure to institute back-up contraception after the missed doses. In cases of repeated omissions of combined hormonal contraceptives, emergency contraception may be required, and back-up contraception should be used. Health care professionals should counsel women in these situations on alternative methods of contraception that do not demand such stringent compliance. (III-A).

Oral contraceptives for functional ovarian cysts

BACKGROUND

Functional ovarian cysts are a common gynecological problem among women of reproductive age worldwide. When large, persistent, or painful, these cysts may require operations, sometimes resulting in removal of the ovary. Since early oral contraceptives were associated with a reduced incidence of functional ovarian cysts, many clinicians inferred that birth control pills could be used to treat cysts as well. This became a common clinical practice in the early 1970s.

OBJECTIVES

This review examined all randomized controlled trials that studied oral contraceptives as therapy for functional ovarian cysts.

SEARCH STRATEGY

We searched the computer databases of CENTRAL, PubMed, POPLINE, and EMBASE for randomized controlled trials. We also examined the reference lists of articles and wrote to authors of all studies identified to seek articles we had missed.

SELECTION CRITERIA

We included randomized controlled trials in any language that included oral contraceptives used for treatment and not prevention of functional ovarian cysts. Criteria for diagnosis of cysts were those used by authors of studies.

DATA COLLECTION AND ANALYSIS

Two authors independently abstracted data from the articles and entered them into RevMan 4.2. We used Peto odds ratios with 95% confidence intervals for dichotomous outcomes.

MAIN RESULTS

We identified four randomized controlled trials from three countries; the studies included a total of 227 women. Treatment with combined oral contraceptives did not hasten resolution of functional ovarian cysts in any trial. This held true for cysts that occurred spontaneously as well as those that developed after ovulation induction. Most cysts resolved without treatment within a few cycles; persistent cysts tended to be pathological (e.g., endometrioma or para-ovarian cyst) and not physiological.

AUTHORS' CONCLUSIONS

Although widely used for treating functional ovarian cysts, combined oral contraceptives appear to be of no benefit. Watchful waiting over several cycles is appropriate. Should cysts persist, surgical management is often indicated.

Effects of oral contraceptives administered at defined stages of ovarian follicular development

OBJECTIVE

To elucidate the effects of initiating oral contraceptives (OC) at defined stages of ovarian follicle development.

DESIGN

Prospective longitudinal study.

SETTING

Healthy volunteers in an academic research environment.

PATIENT(S)

Forty-five healthy women between the ages of 18 and 35 years, randomized to initiate OC when a follicle diameter of 10, 14, or 18 mm was first detected.

INTERVENTION(S)

The OC administration at defined stages of dominant follicle development.

MAIN OUTCOME MEASURE(S)

Fates of all dominant follicles and serum concentrations of E(2)-17beta, LH, and P before and after initiating OC.

RESULT(S)

No ovulations (0/16) were observed when OC use was initiated at a follicle diameter of 10 mm, 4/14 (29%) follicles ovulated when OC were initiated at 14 mm, and 14/15 (93%) ovulated when OC were initiated at 18 mm. When ovulation did not occur, follicles regressed or became anovulatory cysts. Peak LH and E(2) levels were lowest in the 10-mm group, moderate in the 14-mm group, and greatest in the 18-mm group. Peak endocrine levels in all treatment groups were lower than the historic reference group.

CONCLUSION(S)

Follicular development, ovulation, and endocrine concentrations were not suppressed effectively when OC were initiated at late stages of dominant follicle development.

Ovarian follicular dynamics during conventional vs. continuous oral contraceptive use

OBJECTIVES

The purpose of this study was to characterize ovarian follicular and endometrial development during conventional vs. continuous oral contraceptive (OC) dosing regimens, to explore follicular development during the hormone-free interval (HFI) and to examine follicular development following OC discontinuation.

STUDY METHODS

A randomized clinical trial involving 36 clinically normal healthy women between the ages of 18 and 35 years (24.4 +/- 3.9, SEM). Transvaginal ultrasonography and blood sampling were done to ascertain ovarian function.

RESULTS

Fewer follicles > 4 mm developed during continuous vs. conventional OC use (p = .006). No dominant follicles developed during continuous OC use vs. eight dominant follicles (16.1 +/- 3.3 mm) during the conventional OC regimen. Two of eight (25%) dominant follicles ovulated. All dominant follicles began development during the HFI. Following discontinuation of OC use, ovulation took approximately 5 days longer when compared to natural cycles.

CONCLUSION

Continuous OC regimens more effectively prevent dominant follicle development and breakthrough ovulation. The slight delay in time to ovulation following OC discontinuation and natural cycles could be attributed to suppression of follicle wave activity.

Safety concerns and health benefits associated with oral contraception

Since the introduction of hormonal contraceptives in the 1960s, there have been a variety of both health benefits and safety concerns attributed to their use. In most instances, the noncontraceptive benefits of oral contraceptives (OCs) outweigh the potential cardiovascular risks. In fact, the probability of a patient experiencing a cardiovascular event while taking a low-dose OC is very low. However, smoking, hypertension, obesity, and diabetes are risk factors that must be taken into account when prescribing OCs. The neoplastic effects of hormonal contraceptives have been extensively studied, and recent meta-analyses indicate that there is a reduction in the risk of endometrial and ovarian cancer, a possible small increase in the risk for breast and cervical cancer, and an increased risk of liver cancer. Finally, many women will experience noncontraceptive health benefits with OCs that expand far beyond pregnancy prevention. Some of these benefits include reduction in menstrual-related symptoms, fewer ectopic pregnancies, a possible increase in bone density, and possible protection against pelvic inflammatory disease.

Ovarian follicular development during the use of oral contraception: a review

Over the past 40 years, alterations to the composition of oral contraceptives (OCs) have been made in attempts to reduce adverse effects and to improve patient compliance while maintaining contraceptive efficacy. However, there is growing evidence to indicate that reducing the estrogen dose to minimize adverse effects may have compromised the degree of hypothalamo-pituitary-ovarian suppression, particularly during the hormone-free interval (HFI) or following missed doses. Follicle development during OC use appears to occur in association with a loss of endocrine suppression during the HFI. This information provides a rationale for reducing or eliminating the HFI in OC regimens. There is also evidence for an increased risk of follicle development and ovulation in women who use delayed OC initiation schemes, such as the "Sunday Start" method. It is not currently known why some follicles ovulate during OC use while others regress or form anovulatory follicle cysts. Continued research about follicle development during OC use would provide insight into understanding the precise mechanisms of action underlying combined OCs, as well as those of continuous OC formulations and emergency contraceptive regimens.

Oral contraceptives: current status

During the past four decades, oral contraceptives have remained a safe and effective method of birth control. Reductions in the estrogen and progestin dosages have significantly decreased the incidence of cardiovascular complications. The association between oral contraceptives and breast cancer appears to be primarily because of detection bias or possibly a promotional effect. Despite the changes in formulation, the problems related to side effects have not been totally solved. Because compliance and successful use is strongly affected by side effects, improvement in this area is probably the biggest challenge faced by developers of oral contraceptives. It is also clear that there are a growing number of significant noncontraceptive benefits that accrue in oral contraceptive users. Unfortunately, many women do not know about these benefits. Thus, one of the issues that providers need to continue to address is how to provide better information about oral contraceptives and contraception in general to patients.

Health benefits of oral contraceptives

A sizeable literature corroborates the multiple health benefits of oral contraceptive use. The first estrogen/progestin combination pills were marketed to treat a variety of menstrual disorders. Although currently used oral contraceptives no longer carry FDA-approved labeling for these indications, they remain important therapeutic options for a variety of gynecologic conditions. Well-established gynecologic benefits include a reduction in dysmenorrhea and menorrhagia, iron-deficiency anemia, ectopic pregnancy, and PID. Although older, higher-dose pills reduced the incidence of ovarian cysts, low-dose pills suppress follicular activity less consistently. Nevertheless, cycle-related symptoms, including functional cysts, dysmenorrhea, chronic pelvic pain, and ovulation pain (mittelschmerz), generally improve. Women with polycystic ovary syndrome note improvement in bleeding patterns and a reduction in acne and hirsutism. Symptoms from endometriosis also improve with oral contraceptive therapy. Current data suggest that oral contraceptive therapy increases bone density and that past use decreases fracture risk. Oral contraceptives also improve acne, a major health concern of young women. Oral contraceptives provide lasting reduction in the risk of two serious gynecologic malignancies--ovarian and endometrial cancer. The data with respect to ovarian cancer are compelling enough to recommend the use of oral contraceptives to women at high risk by virtue of family history, positive carrier status of the BRCA mutations, or nulliparity, even if contraception is not required. Health care providers must counsel women regarding these benefits to counteract deeply held public attitudes and misconceptions regarding oral contraceptive use. Messages should focus on topics of interest to particular groups of women. The fact that oral contraceptives increase bone mineral density and reduce ovarian cancer is of great interest to women in their forties and helps influence use and compliance in this group. In contrast, the beneficial effects of oral contraceptives on acne resonates with younger women. Getting the good news out about the benefits of oral contraceptives will enable more women to take advantage of their positive health effects.

Multicenter study of the efficacy, cycle control and tolerability of a phasic desogestrel-containing oral contraceptive

OBJECTIVE

To investigate the efficacy, cycle control and tolerability of a phasic oral contraceptive containing ethinylestradiol 35/30/30 microg and desogestrel 50/100/150 microg.

METHODS

A multicenter study was conducted involving 2070 healthy, fertile women, who received study treatment for six treatment cycles.

RESULTS

Most of the participants (79%) had previously been using an alternative oral contraceptive. In 10,408 treatment cycles, two women became pregnant while on treatment (Pearl index, 0.25). The incidence of irregular bleeding was 10% before treatment, rising to 27% at cycle 1, and decreasing to 11% by cycle 6. Irregular bleeding was mainly due to spotting rather than breakthrough bleeding and the incidence of breakthrough bleeding remained below 2.2% for most of the study period. Only 1.8% of women withdrew due to bleeding irregularities. First-time oral contraceptive users initially experienced more irregular bleeding than switchers but these differences lessened over time. The most common adverse events during treatment were headache, breast tenderness and nausea. The incidence of these adverse events fell to below pretreatment levels with continued use.

CONCLUSION

The phasic preparation was effective and well tolerated.

Oral contraceptive use and benign gynecologic conditions. A review

The following review considers the main epidemiologic data on oral contraceptives (OC) and the risk of major benign gynecologic diseases. Earlier studies investigating the relationship between OC use and functional ovarian cysts indicated that the use of high-dose combination OC have a protective effect, whereas low-dose monophasic or multiphasic pills have little or no effect. With regard to seromucinous cysts, the scanty data available are consistent with the notion of some protection of OC in current but not in former users, although possible effects of diagnostic and selection bias should be considered. Published data on the relationship between fibroids and OC appear too scattered to allow a precise quantification of risk. In any case, any relationship is moderate and, hence, of limited clinical and public health relevance. The data on OC and benign gynecologic conditions are reassuring in their absence of any consistent excess risk.

A comparative randomized trial on the impact of two low-dose oral contraceptives on ovarian activity, cervical permeability, and endometrial receptivity

In a double-blind randomized study, the suppression of ovarian activity and anti-conceptive effects on the cervix and endometrium were assessed during administration of two low-dose monophasic oral contraceptives (20 micrograms ethinyl estradiol [EE], 500 micrograms norethisterone--Eve 20 [Grünenthal, Aachen, Germany]; 20 micrograms EE, 150 micrograms desogestrel --Lovelle [Organon, Munich, Germany]). One hundred eighteen healthy women (ages: 18-35 years) were studied in 10 investigation centers during medication with either Eve 20 (n = 59) or Lovelle (n = 59). During three treatment cycles, ovarian activity was evaluated by sonographic determination of follicle-like structures (FLS) and by simultaneous assessment of serum endocrine profiles (gonadotropins LH and FSH, ovarian steroids estradiol [E2] and progesterone [P]). While on either treatment, no ovarian activity (as judged by no FLS and/or reduced sex steroid levels) was found in 90.8% (Eve 20) and 97.2% (Lovelle) of all investigated cycles. Follicular activity or cyst formation were detected in 18 of 173 cycles (Eve 20) and in 5 of 175 cycles (Lovelle), respectively. Gonadotropin levels were suppressed (LH < 6 IU/L, FSH < 8 IU/L) in most treatment cycles (Eve 20 76.6% vs. Lovelle: 84.8%). Serum E2 concentrations exceeding 0.1 nmol/L indicated residual follicular activity in 19.3% (Eve 20) versus 12.2% (Lovelle) of all cycles. An estimated by serum P levels over 5 nmol/L, ovulation had presumably occurred in 4.1% (Eve 20) versus 2.9% (Lovelle) of treatment cycles. However, when the sonographical and endocrinological data were combined, no ovulation was documented in any pill cycle. The quality and quantity of the cervical mucus was found to be minimal in the majority of women. Moreover, the endometrial layer was determined to be low by ultrasound during most pill cycles, indicating equally strong suppressive effects on endometrial receptivity by the two contraceptives. These observations suggest that ovarian activity is suppressed in the majority of cycles during use of low-dose contraceptives. This effect may mainly be medicated by pronounced suppression of serum gonadotropin levels. Strong anti-conceptive effects of these formulations on both cervical permeability and endometrial receptivity are additional factors ensuring the contraceptive efficacy of these formulations.

Oral contraceptives and sexuality in university women

The relationship between use of oral contraceptives and sexuality in university women who completed the McCoy Female Sexuality Questionnaire was examined. Pill users reported sexual intercourse earlier, were less likely to be virgins, more likely to have a sex partner, more apt to be engaging in petting and intercourse than nonusers, and reported more frequent intercourse than sexually active nonusers. Nonusers reported a greater frequency and enjoyment of anal intercourse than pill users. The prediction that pill users would have less vaginal lubrication than nonusers was supported. Contrary to prediction, pill users reported a higher frequency of sexual thoughts and fantasies, and level of sexual interest than active nonusers. Triphasic Orthonovum 7/7/7 (OR7/7/7) users reported more sexual thoughts and fantasies and had higher Sexual Interest (Factor 1) scores than monophasic Orthonovum 1/35 (OR1/35) users. Triphasic users as a group enjoyed sexual activity more, were more aroused during sexual activity, and had higher Sexual Interest factor scores than monophasic users. Triphasic users reported more sexual thoughts and fantasies, sexual interest and had higher Sexual Interest factor scores than nonusers, while monophasic users did not. Monophasic users reported less vaginal lubrication than nonusers, whereas triphasic users did not. Comparisons of OR7/7/7 and OR1/35 users with nonusers revealed the same findings. Results suggest that women using triphasic pills experience greater sexual interest and response than those using monophasics. Possible reasons for these differences are discussed.

Ovarian activity suppression by two different low-dose triphasic oral contraceptives

In an open, randomized study in an outpatient clinic of a large teaching hospital, thirty-one female volunteers with regular cycles and established ovulation by ultrasonography were given one of two triphasic oral contraceptives containing ethinylestradiol combined with levonorgestrel or desogestrel during six cycles of treatment. The main outcome measures were transvaginal ultrasonography and serum E2 and P measurements in pill cycles 1, 3 and 6. No ovarian activity was found in 10 subjects. Among the remaining 21 women who showed ovarian activity, most follicle-like structures developed in the pill-free week and decreased in size or disappeared in the first pill week. One women taking triphasic desogestrel had evidence of a luteinized unruptured follicle and one women taking triphasic levonorgestrel had a possible ovulation. The latter women also showed symptoms of lower abdominal pain. A statistically significant difference in ovarian activity between the two oral contraceptives could not be established. The two triphasic oral contraceptives suppressed ovarian activity to the same degree. A trend was seen towards increasing ovarian activity with duration of use in both treatment groups.

The influence of the dose of ethinylestradiol in oral contraceptives on follicle growth

This prospective, randomized comparative clinical study involving 416 women investigated follicle development over a period of 12 oral contraceptive treatment cycles. Women were allocated to two groups, one group (n = 207) received a preparation containing 30 micrograms ethinylestradiol and 75 micrograms gestodene daily, and the other group (n = 209) received 20 micrograms ethinylestradiol and 150 micrograms desogestrel, daily. Follicular development was monitored by transvaginal ultrasonography of the ovaries, during days 18-21 in the pretreatment cycle and in treatment cycles 1, 3, 6, 9 and 12. Follicular development was found to be twice as frequent in the group receiving 20 micrograms ethinylestradiol/desogestrel as in the group receiving 30 micrograms ethinylestradiol/gestodene. For all cycles, follicles of 10-30 mm were found in 18% of women in the desogestrel group, compared with 9.7% in the gestodene group, whilst follicles with a diameter of >30 mm were present in 5% of the desogestrel group compared with 1.9% of the gestodene group. The difference between the treatment groups with respect to follicle diameters of 10-30 mm and >30 mm was statistically significant (p < 0.05 and p < 0.001, respectively). No ruptured follicles were observed in either group throughout the study, suggesting that there was no escape ovulation, however, there was one pregnancy in the desogestrel group that could not be explained either by drug interactions or missed pills. It can be concluded that the ethinylestradiol dose in an oral contraceptive has a significant effect on follicular ovarian activity, and that reducing the dose to 20 micrograms is associated with a significant increase in follicle size.

Enlarged follicles in women using oral contraceptives

Ultrasound examination of the ovaries was performed in the first and/or second half of three consecutive cycles in 3 groups of women; Group T who had been using a levonorgestrel triphasic oral contraceptive for at least 6 months, Group P who had been using a progestogen-only pill for at least 6 months, and Group C, a control group. Any follicles greater than 10 mm in diameter and any cysts were measured. Fifty-three scans were performed in Group T, 45 in Group P and 31 in Group C. Only 4 follicles were detected in 17 women in Group T compared to 10 follicles in 15 women in Group P and 7 follicles in the women in Group C; all follicles were 25 mm or less in diameter except for 3 follicles in 2 women. The differences between the groups were not statistically significant. Four enlarged follicles were detected in 3 women during 53 scans in Group T, 15 in 8 women (45 scans) in Group P, and only 1 in 31 scans in Group C. Based upon the proportions of scans with enlarged follicles, the difference between Groups T and P was statistically significant, indicating that the incidence of enlarged follicles was lower in women using a combined oral contraceptive than in those using a progestogen-only pill. Furthermore, the study shows that any enlarged follicles which occurred were transient.

Ovarian function during low-dose oral contraceptive use

Lowering the total steroid dose in modern oral contraceptives (OCs) has been connected with a higher incidence of ovarian follicle and cyst formation. To investigate the presence of ovarian follicles and cysts by means of vaginal ultrasonography and serum hormone determinations during use of two low-dose OCs, 65 volunteers were randomized to receive either 20 micrograms ethinylestradiol (EE) + 150 micrograms desogestrel (group A) or 35 micrograms EE + 250 micrograms norgestimate (group B) for a 2-month study period. At baseline, 39% of women in group A and 31% in group B exhibited at least one follicle < 35 mm in diameter. By the end of the second treatment cycle, the frequency of these follicles had decreased to 14% in each group. Only one subject in the higher estrogen group developed an ovarian cyst > 35 mm. One subject in each group demonstrated hormone levels characteristic of ovulation; no pregnancy occurred in either group. The 20 micrograms EE preparation was not found to lead more often to ovarian follicles or cysts when compared with a 35 micrograms EE preparation, possibly because of the type and dose of the progestogen used.

Combined oral contraceptives: do we know all of their effects?

Combined oral contraceptives are undoubtedly popular. By the end of the 1980's, an estimated 63 million married women around the world were using this method of contraception. In Britain, perhaps 95% of all sexually active women have used the pill at some time before their 30th birthday. Commensurate with such widespread usage, huge amounts of money have been spent during the past 35 years investigating the health effects of this method of contraception. Since it appears that all of the potential risks and benefits have now been identified, can we divert resources from pill-related research into new areas of activity. While this proposition may be attractive to funding bodies, and other researchers competing for increasingly scarce resources, it ignores the fact that several major uncertainties remain concerning the safety of combined oral contraceptives.