Feet a blur, I pedalled my bike as fast as possible down the canal towpath, pot of semen in my rucksack, desperate to get to the hospital in time to conceive. Of all the bewildering, life-changing, traumatic experiences of the IVF process, this is the one I most remember now, the winter slipstream on my sweaty face, all the dreams of my partner and I contained in a plastic pot nestled next to laptop, book and bike lock. We had been trying to have a child for a while, timing sex with apps and temperature readings, drinking little, taking supplements, but nothing had worked.

The months ticked on. Admitting defeat, we went to the local doctor, who helpfully said that the universe told her we would conceive. Did she say that to everyone? Thankfully, the universe also told her to refer us to our local hospital for initial investigations into our fertility, and potential IVF treatment.

The introductory lecture was packed with couples in their late 20s to early 40s. The atmosphere was one of nervous energy as our collective presence in the room made public an intimate struggle. There was an audible gasp, and pointed glances from women to their male partners, when the doctor told us that male fertility has declined by 50% since the second world war.

Most of us clearly had no idea, but there it was, on a graph on the screen. Sperm count, concentration, motility (how well the sperm can “swim”) and morphology (the quality of the sperm) is decreasing, though scientists don’t conclu.