So it is with some trepidation that I consider the likelihood of this ‘breakthrough’ ever becoming a reality – not because of the usual fate of such proclamations, but moreso because the whole premise is based on successful experimentation on mice.
The male mice used in this study were genetically modified (contained a mutated gene) and sexually matured at 10-12 weeks of age. They were mated with wild-type female mice in cages fitted with infrared video-recording equipment. Fourteen days after copulation the females were killed and checked for pregnancies. The males then had their blood pressure and pulse monitored and their sperm was extracted (no description of how this was achieved) and analysed under a microscope.
The results were that no sperm was mixed with ejaculate, so it was not released, and resulted in no pregnancies. Of particular interest however, was that the infertility was readily reversible.
Another ‘breakthrough’ study, conducted by the University of Chicago, also focused on the development of a male contraceptive – again in mice. Once again, they established infertility in the male which was also reversible, and the data, it was suggested, “represents another approach toward the development of a male contraceptive”. That study was submitted for publication in 1989... need I say more?
Admittedly we do share some characteristics and some DNA with Mus musculus, however there are also many differences. In the case of this particular issue (fertility), the reproduction habits of mice are quite different to our own. For example if females are housed together without males, they will not come into estrus (heat), however when exposed to male urine they will come into estrus within 72 hours. Not so with us ladies! And being an animal of prey, they produce litters of 3 and 14 young and can have five to ten litters per year. Imagine! So, you’ll have to pardon my cynicism as to whether data that the scientists obtained from this mouse experiment can truly be extrapolated to the human male with any degree of certainty.
There is another angle to consider. The paper states:
“…male infertility would have to be 100% in preclinical studies for a novel therapeutic target for male contraception to be considered viable in humans.”
Considering the species differences (anatomic, genetic, metabolic etc.) between mice and humans, as well as the fact that nine out of ten drugs deemed successful in animal trials fail in human clinical trials (that’s the US FDA figures), there's every possibility that those animal studies which failed to attain 100% infertility could have actually been successful in humans. Could we therefore have inadvertently discarded a male contraceptive based on the failure of animal tests?
Finally, all research on animals is supposed to be subject to a cost/benefit analysis. Now I’m certainly in favour of curtailing human population growth and understand its’ importance, but I just don’t believe that performing sexual experiments on mice is the way to go about it.
Do we not have a diverse array of contraception already available to us? There are several versions of the female pill, condoms, vasectomies and abstinence. So, we certainly can’t argue that the development of a male pill is absolutely necessary for the advancement (or not) of humankind.
And ladies even if, ten years down the track, this particular research does correlate to humans and results in the elusive male pill, how likely will it be that males will actually commit to a daily dose? Much as we may love the other sex, would you put your absolute trust and faith in the male of the species doing this? I think we females may just be well advised to continue taking other precautions… just in case!