In vanilla Valheim, as of this writing, breeding includes a mechanic that utilizes "lovePoints". Creatures must reach a required number of lovePoints before pregnancy occurs, and lovePoints are incremented by one every time a creature breeds. Thus, pregnancy only occurs every n-th breeding (usually 3). Creatures that are overcrowded won't breed even when lovePoints are too low for pregnancy.

This mod allows creatures to breed for lovePoints even when the area is too crowded for pregnancy, and it allows some excess points to be accumulated in those conditions.

During crowded conditions:
- Animals with no lovePoints are less likely to breed, but the chance increases the closer the animal gets to the lovePoint amount needed for pregnancy.
- Animals with more lovePoints than are needed are also less likely to breed as their lovePoints get higher.
- Animals will accrue only enough lovePoints to allow 2 consecutive successful breedings once overcrowding is corrected.

This means that if you've left your animals in crowded conditions, they might not need to breed as often before pregnancy happens once you cull some to give them room to produce. Leave them in crowded conditions long enough, and they'll get pregnant on two consecutive breeding attempts once there is room (and a near-enough partner). They will also tend to produce more offspring before overcrowding slows production to a near-halt; they can build up enough lovePoints to take advantage of the occasional sparse area in a pen as animals move around.