This week, I was made aware by a Trainer Hormone Factor of a new contraceptive that is in a testing phase, namely Mifegyne with the active ingredient mifepristone.
Mifepriston - Mifegyne
I keyed in the substance name on google. This search also led me to a fragment of Radio 1. A gynaecologist and a medical researcher were singing the praises of this new contraceptive pill without hormones, which is said to have no unpleasant side effects and only needs to be taken weekly.
Watching this excerpt, I was shocked by the lack of doubts about the long-term safety of this product. My advice to these well-meaning ladies is: "Don't cheer too soon, please!"
Drug to trigger abortions
High time, then, to take a closer look at this drug. Mifepristone has long been used as a drug to induce abortions. In this case, it stimulates the contraction of the uterus and suppresses the implantation function of the endometrium. Mifepreston actually has an anti-progestagenic effect, meaning that it inhibits the receptors of the hormone progesterone blocks. It also enhances the action of prostaglandins, which in turn have a function in shedding endometrium.
From this mechanism of action, pharmacists came up with the idea of exploring this drug as a contraceptive. This is because if you prevent the development of healthy and fertile endometrium with mifepreston, pregnancy cannot occur either. So you can develop a contraceptive pill that can be effective while the ovaries still just oestrogen and continue to produce progesterone.
As a contraceptive, you only need to take mifepristone in lower doses every week and there are few known short-term side effects, apart from the positive side effect of reduced menstrual bleeding. In recent weeks, several media outlets and influencers appear to have hurled messages about mifepristone into the world as if coming up with this 'hormone-free contraceptive pill' is some kind of 'eureka' moment.
My opinion on this contraceptive pill
I myself am a lot more careful in my statements. True, there are no hormones in this pill, but you are affecting the hormonal balance.
- Thus, while it may sometimes be desirable to block progesterone receptors from the endometrium, what happens to progesterone receptors in the rest of the body? Does it then also block the action of progesterone receptors in osteoblasts? Indeed, in osteoblasts, progesterone can stimulate the production of bone tissue.
- And what about the effect of mifepristone on the action of progesterone in the brain, where, for example, it stimulates the production of neurotransmitter GABA?
- Furthermore, mifepristone is known to not only suppress the action of progesterone, but also that of cortisol.
So there is still very much unknown when it comes to the long-term effects on the whole body of this contraceptive method. So I certainly don't see this remedy as harmless yet. Also women's doctor Barbara Havenith has her doubts when asked: "We have experience with the occasional use of anti-progestogens, but what they do in intermittent chronic use we cannot yet oversee."
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