A randomised study comparing the effect on ovarian activity of a progestogen-only pill (POP) containing desogestrel and a new POP containing drospirenone in a 24/4 regimen

Abstract

Objectives Progestogen-only pills (POPs) are safer with respect to cardiovascular risks than contraceptives containing estrogens. Despite the increased contraceptive efficacy of a desogestrel-only pill compared with a traditional POP, POPs are still not widely used due to an unpredictable bleeding pattern. A new POP containing 4 mg drospirenone has been developed with a 24/4 intake regimen which may improve the bleeding pattern. The objectives of this study were to investigate ovulation inhibition with the new drospirenone-only pill in comparison with the desogestrel-only pill and, in addition, to assess the effects on cervical mucus permeability and bleeding.Methods Sixty-four healthy volunteers with proven ovulatory cycles were randomised and treated with either the drospirenone-only or the desogestrel-only pill during two 28-day cycles. Follicular diameter, endometrial thickness, and serum estradiol (E2) and progesterone concentrations were measured and Hoogland scores were determined. Additionally, cervical mucus scores, bleeding and return of ovulation were assessed.Results Both treatments effectively inhibited ovulation. Follicular diameter, E2 levels and Hoogland scores were equal, demonstrating efficient ovarian suppression. One subject in each group had a Hoogland score of 6, but the criteria for normal luteal activity were not fulfilled. In both groups, ovulation did not occur before day 9 of the post-treatment cycle. Cervical mucus permeability was suppressed in both groups. The median number of bleeding and spotting days was lower in the drospirenone group.Conclusions The new drospirenone-only pill inhibited ovulation as effectively as the desogestrel-only pill despite the 4-day hormone-free interval.Chinese 摘要目的 对于心血管疾病风险，纯孕激素避孕药比含雌激素的避孕药安全。尽管只含去氧孕烯的避孕药与传统纯激素避孕药相比，避孕效果增加了，由于不可预知的出血模式，纯孕激素避孕药仍没有被广泛应用。包含4毫克屈螺酮的新型纯孕激素避孕药已被研制出，采用24/4方案可以改善出血模式。这项研究的目的是调查仅含屈螺酮的新型避孕药与仅含去氧孕烯的避孕药相比对排卵抑制的情况，此外，也用于评估对宫颈粘液穿透性和出血的影响。方法 经过验证有排卵周期的64名健康志愿者，在两个28天的周期中被随机给予仅含屈螺酮或者去氧孕烯的避孕药。测定卵泡直径、子宫内膜厚度、血清雌二醇和孕激素浓度，并进行Hoogland评分。此外，对宫颈粘液评分、出血及排卵抑制进行评估。结果 两种治疗方法都能有效的抑制排卵。卵泡直径、雌二醇水平和Hoogland评分都是相同的，以及证明有效的排卵抑制。每组每一项的Hoogland评分都是6，但是黄体活动的标准还没有制定。在预处理周期的第9天以前，两个组都不会出现排卵。两个组的宫颈粘液穿透性都被抑制了。在屈螺酮组中，黄体期出血天数的中位数比较低。结论 尽管有4天无激素的时间间隔，仅含屈螺酮的新型避孕药与仅含去氧孕烯的避孕药对排卵的抑制效果是一样的。关键词去氧孕烯片；去氧孕烯；屈螺酮；卵巢活动；排卵抑制；纯孕激素型避孕药