Ferning In Cervical Mucus

At ovulation the cervix secretes a very clear mucus that is receptive to sperm cells but also acts as a filter to weed out bacteria and unhealthy sperm cells whilst nurturing the healthy ones. The change in the mucus at this time is characterised by an increase in Sodium salts. As a result, it produces these rather beautiful fern-like crystals within it as it dries. This only happens around ovulation. Fertility clinics used to use this to identify when a women was at exactly the right point in her reproductive cycle for artificially inseminating her. Sadly, technology has moved on and this method is no longer used.
These crystals have been filmed in time lapse using a polarising microscope.
These video clips and others like them can be found in the David Barlow Film Archive at :
www.davidbarlow...

[@alysiam.8065]

So cool. It's like I'm looking at a winter setting.

[@radiancewithin951]

Incredible!!

[@jibba0202]

What magnification is this?

[@davidbarlowarchive]

I can't remember exactly but probably around X30 on the film and nearer 300X when you watch the video at full size. The microscope objective would have been X10 with a X3 projection eyepiece to focus the image on the film plane.