You guys have weird female friends.
Most of my female friends know more about penises than I do.
Also, that story about the german couple sounds highly implausible to me...they must have led a life completely isolated from magazines, newspapers, TV and social connections.
They must also have opressed any natural instincts, or simply resented bodily contact, since an intimite couple driven by lust eventually (after 6 years) will find out the procedure of sex almost by coincidence.
Additionally, they must have lacked common sense, believing that her pregnancy would occur without any prior cause.
Socially isolated, mentally inhibited and plain stupid.