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Hormonal contraceptives have proved to be safe and highly reliable. Most hormonal contraceptives are taken orally, and most oral contraceptives are a combination of a man-made estrogen such as ethinyl estradiol and a derivative of progesterone. They block ovulation and induce changes in the lining of the uterus that lower the chances of fertilization and implantation. Combined oral contraceptives lower women's risks for cancers of the ovary and uterine lining, but appear to increase the risk of breast cancer slightly. Oral contraceptives with low doses of estrogen are not associated with an elevated risk of cardiovascular disease. Combined oral contraceptives appear to induce high blood pressure in 4% to 5% of women and to increase blood pressure in 9% to 16% of women who already have high blood pressure. Some developments in hormonal contraceptives include skin implants, hormone-releasing intrauterine devices and hormone agonists and antagonists.

Many women find the idea of a once-a-month contraceptive pill an attractive concept. Mifepristone has been shown to be effective as a contraceptive if administered in the early luteal phase. We tested the contraceptive efficacy of 200 mg of mifepristone on day luteinizing hormone (LH) + 2 in a group of 32 women who used a fertility monitor to identify the LH surge. We also recruited a control group, comprising 20 women who were trying to conceive. In this group, 12 women conceived during a total of 50 control cycles (probability of pregnancy 0.25–0.32). Women in the treatment group contributed to a total of 178 cycles and there were two pregnancies (probability of pregnancy 0.01). An LH surge was not detected in 34 cycles (19.1%). In 20 cycles (11.2%) this was due to imperfect use while 14 were monitor method failures (7.9%). Treatment with mifepristone in the early luteal phase did not disrupt the cycle length but women reported slight vaginal bleeding in 15% of the cycles. The combination of a home-use fertility monitor with once-a-month administration of mifepristone (especially if mifepristone is administered at the early luteal phase) is an acceptable contraceptive option with minimal side effects. Unfortunately, it is difficult to envisage how an easier way of defining the correct timing, which required less compliance, could be devised. [ABSTRACT FROM PUBLISHER]

We have measured the activity of glucose phosphate isomerase (GPI-1) in 12 unfertilized human eggs and five human pre-embryos relative to the GPI-1 activity in C57BL/OlaWs mouse eggs. The GPI-1 activity in the human eggs was approximately 6 times that in the C57BL mouse eggs. This implies that human eggs have approximately twice the activity per unit volume of the C57BL mouse eggs but no more than certain other strains of mice. The activity in five human pre-embryos, the most advanced of which was an early blastocyst, was similar to that seen in the human eggs. No change in GPI-1 activity was seen in mouse pre-embryos up to 2 1/2 days (8- to 12-cell stage) but the activity had declined by 3 1/2 days (compacted morula and early blastocyst stages). It seems that high levels of GPI-1 activity are maintained during the early preimplantation development of both species. [ABSTRACT FROM AUTHOR]

Background: The levonorgestrel-releasing intrauterine system (LNG-IUS) is a highly effective contraceptive. However, during early months of use unscheduled vaginal bleeding is common, sometimes leading to discontinuation. This study aimed to determine whether intermittent administration of progesterone receptor modulator CDB-2914 would suppress unscheduled bleeding during the first 4 months after insertion of the LNG-IUS.Methods: CDB-2914 150 mg, in divided doses, or placebo tablets, were administered over three consecutive days starting on Days 21, 49 and 77 after LNG-IUS insertion, in a double-blind randomized controlled trial of women aged 19-49 years, newly starting use of LNG-IUS. Daily bleeding diaries were completed for 6 months, and summarized across blocks as percentage days bleeding/spotting (BS%).Results: Of 69 women randomized to receive CDB-2914, and 67 placebo, 61 and 55, respectively, completed the trial. BS% decreased with time in both arms, but showed a much steeper treatment-phase gradient in the placebo arm (P < 0.0001), so that a benefit of CDB-2914 in the 28 days after first treatment (-11% points, 95% CI -19 to -2), converted to a disadvantage by 64 days after the third treatment (+10% points, 95% CI 1-18).Conclusions: The effect of CDB-2914 on BS% was initially beneficial but then by third treatment was disadvantageous. Nevertheless, only 3% (4/136) of all women discontinued LNG-IUS. These findings give insight into possible mechanisms and suggest future research directions. ISRCTN Trial no. ISRCTN58283041; EudraCT no. 2006-006511-72. [ABSTRACT FROM AUTHOR]

Background: The acceptability and continuation rate of oral contraceptive steroids are limited by unpredictable bleeding and the fear of long-term risks such as breast cancer. By inhibiting ovulation and by altering the receptivity of the endometrium, antagonists of progesterone, such as mifepristone, could be developed as estrogen-free novel contraceptives. Methods: Multicentre, double-blind, randomized controlled trial comparing frequency of amenorrhoea (primary outcome), bleeding patterns, side effects and efficacy in women taking daily 5 mg mifepristone (n = 73) or 0.03 mg levonorgestrel (progestogen-only pill; POP, n = 23) for 24 weeks. Results: More women were amenorrhoeic while taking mifepristone than POP (49 versus 0% P < 0.001), and fewer women bled or spotted for >5 days per month (4 versus 39% P < 0.001). Forty-eight percent of women who took mifepristone for 6 months had cystic glandular dilatation of the endometrium but none showed hyperplasia or atypia. There were no pregnancies in 356 months of exposure in women who used only mifepristone for contraception. Two pregnancies occurred in women taking mifepristone who were also using condoms for dual protection. Conclusions: Daily mifepristone (5 mg) is an effective oral contraceptive pill which has a better pattern of menstrual bleeding than an existing POP (levonorgestrel). [ABSTRACT FROM AUTHOR]

Despite a renewed interest in the development of hormonal contraceptives for men, many discussions about the potential acceptability of a 'male pill' end by speculating whether women would trust their partners to use the method reliably. To determine the views of women, we undertook a survey of 1894 women attending family planning clinics in Scotland (450), China (900) and South Africa (544). In all centres over 65% of women thought that the responsibility for contraception falls too much on women. More than 90% in South Africa and Scotland thought that a 'male pill' was a good idea, with Chinese women (71% in Hong Kong and 87% in Shanghai) only slightly less positive. Only 13% of the total sample did not think that hormonal male contraception was a good idea and only 36 women (2% of the total) said that they would not trust their partner to use it. 78% of Scottish women, 71% of Shanghai women, and 78% of white women and 40% of black and coloured women in Cape Town thought that they would use the method. This survey should dispel the myth that women would not trust their partners to use a 'male pill' reliably and illustrates the potential market for the method. [ABSTRACT FROM AUTHOR]

The prospect of a hormonal male contraceptive is no longer distant. Data on the potential impact of this improvement in contraceptive provision, however, is limited, particularly between different cultures. We have therefore carried out a multi-centre study to assess men's attitudes to proposed novel hormonal methods. Questionnaire-based structured interviews were administered to men in Edinburgh, Cape Town, Shanghai and Hong Kong. Approximately 450 men were interviewed in Edinburgh, Shanghai and Hong Kong, and a slightly larger group (n = 493) in Cape Town to give samples (n > 150) of black, coloured and white men. Knowledge of existing male and female methods of contraception was high in all centres and groups. The majority of men welcomed a new hormonal method of contraception, 44-83% stating that they would use a male contraceptive pill. Overall, a pill was more acceptable than an injectable form (most popularly given at 3-6 month intervals); long-acting implants were least so except in Shanghai. Familiarity with comparable female methods appeared to influence acceptability, for both oral and injectable methods. Hong Kong was the only centre where a male method (condom) was currently the most commonly used; men there appeared to rate the convenience of condoms highly while being least likely to think that they provided effective protection against pregnancy compared to other centres, and were least enthusiastic about novel male methods. The acceptability of potential male hormonal methods of contraception was high in some groups but showed wide variability, determining factors including cultural background and current contraceptive usage. These results suggest that the emerging emphasis that men should have greater involvement in family planning will be substantiated when appropriate contraceptive methods become available. [ABSTRACT FROM AUTHOR]