After the contract, any increase belongs to the wife, since the แนฃadรขq is now her property in its entirety (regardless of who is actually in possession of it). If she needs to return half of it because a divorce takes place before the consummation, she returns half of the original แนฃadรขq, keeping the other half as well as any growth/profit that emanated from it. If this growth can easily be separated from the original แนฃadรขq, such as in the case of livestock giving birth, then she returns half of the livestock he gave her, and she keeps the other half, along with all of the newborns. If the gain of the original แนฃadรขq is not easily separated from the original, such as when livestock gain weight, she has the option of returning half of the value of the original แนฃadรขq or half of the existing (fatter) livestock.
In the case of decrease:
If the woman demands the แนฃadรขq but the man procrastinates, and then the value of the แนฃadรขq is diminished or completely wiped out, he is liable for it. This means that if divorce happens after the contract but before consummation, he will have to pay her half of the original value of that แนฃadรขq.
If she does not request it, then it is in his possession as a trust, and the rulings of trusts will apply. He is only liable for the loss if it results from negligence or wrongdoing on his part.
If she receives it, and then it is diminished or completely lost, she is liable. In the case of divorce before consummation, she must return to him half of the original value of the แนฃadรขq, unless he agrees to taking half of the diminished แนขadรขq (like an emaciated cow).