Triphasic versus monophasic oral contraceptives for contraception

Abstract

Triphasic versus monophasic oral contraceptives for contraception.

Metformin or Oral Contraceptives for Adolescents With Polycystic Ovarian Syndrome: A Meta-analysis

“…We also examined other plausible values on the basis of a 10% rate of amenorrhea and a menstrual cycle frequency of 2 per month (mean of 0.95), and a 20% rate of amenorrhea and a menstrual cycle frequency of 3 per month (mean of 0.86) as assumed from the literature on menstrual bleeding pattern in women taking OCP. [44][45][46][47] The SD was fixed for all the 4 analyses and assumed to be 0.1 as reported in the Allen et al 39 The estimate of the treatment effect favored OCP (best case WMD −0.27, P < .01, 95% CI −0.33 to −0.21; worst case WMD −0.19, P < .01, 95% CI −0.25 to −0.13). However, this point estimate represents a 1-to 2-week difference in the frequency of menstrual cycles per month, which is equivalent to 3.24 menstrual cycles per year.…”

“…4 Additionally, menstrual cycle bleeding patterns among healthy women taking OCP over a 12-month period may present with up to a 20% amenorrhea rate (defined as absent menstrual bleed for more than 2 months). [44][45][46][47] The observed amenorrhea could be due to poor compliance with OCP intake, reproductive organs immaturity, and other biological causes such as abnormal endometrial function. Abnormal endometrial function is apparent in other ways in PCOS as adult women with PCOS undergoing fertility treatments with proof of ovulatory cycles still express low pregnancy rates and higher spontaneous miscarriages rates, and menopausal women with PCOS are at higher risk for endometrial cancer.…”

Efficacy and side‐effects of oral contraceptives

“…A Cochrane review has suggested less spotting, breakthrough bleeding or amenorrhea in triphasic versus monophasic COC users but no randomised trials exist to confirm this approach. 2 Clinical trial data for both Qlaira and Zoely suggest that absent withdrawal bleeds are not uncommon, which may not be acceptable to some women. 3,4 Mode of action Contraceptive efficacy is maintained by several mechanisms.…”

A survey of bonobo (Pan paniscus) oral contraceptive pill use in North American zoos

“…Only two bonobos in the survey and three in the RMC DB were treated with the triphasic pill formulation, introduced in the 1980s as a strategy to decrease possible adverse effects of monophasic formulations. The changing concentrations of estrogen and progestin in triphasic pills are designed to mirror hormone fluctuations during the natural cycle [Van Vliet et al, 2011]. A recent comprehensive review comparing efficacy and menstrual bleeding patterns of monophasic and triphasic pills found insufficient evidence to favor triphasic over monophasic pills [Van Vliet et al, 2011].…”

“…The changing concentrations of estrogen and progestin in triphasic pills are designed to mirror hormone fluctuations during the natural cycle [Van Vliet et al, 2011]. A recent comprehensive review comparing efficacy and menstrual bleeding patterns of monophasic and triphasic pills found insufficient evidence to favor triphasic over monophasic pills [Van Vliet et al, 2011]. The RMC agrees with the conclusions of this review and recommends that the first choice of COC for bonobos should be a monophasic pill, but if a female has been given a triphasic pill in the past with no problems, it may be appropriate for her.…”