Wombgifts not dropping

I have no issue whatsoever to find graftblood, but for some reason it's very rare now to find wonbgifts, especially the ones that don't give grafts.
In general, hive fortress encounters give some wombgifts, but it's especially the other encounter types that don't give them. Even though I kill all monsters without any issue.

Now my equipped grafts don't have any modifier influencing wombgift drops, but I didn't have any drop issue either before.

I started noticing this issue maybe 2 weeks ago, but it's even worse now in the Phrecia 2.0 event...