Or HaChaim on Exodus 1:20/אור החיים על שמות א׳:כ׳

1 וייטב אלוקים למילדות, G'd dealt well with the midwives, etc. We are entitled to know what precisely were the favours G'd did for the midwives. Perhaps the verse alludes to the houses that are described in the next verse. If that were so, however, there would have been no point in interrupting this sequence by stating that "the people increased and became very powerful." It appears rather that the verse explains the cause of the increase in the numbers of Israelites. The very food and water which the midwives provided resulted in G'd dealing well with the midwives. G'd enabled the midwives to continue their economically expensive efforts to feed the many newly born babies. Had G'd not helped them economically, they would not have had the wherewithal to supply all that food which resulted in the increase of the numbers of Israelites. The Torah reports the reward G'd provided for the midwives themselves only in the next verse where we are told that He built houses for them.

2The Torah may also have hinted that when G'd realised the degree of piety demonstrated by the midwives, He decided to reward them by providing them with unlimited opportunities to continue their good work. The word וייטב is followed by וירב העם to show cause and effect. The "good" G'd did for the midwives was that they saw their efforts rewarded by an increase in the Israelite population. Who knows if leaders such as Moshe and Aaron were not provided by G'd for Israel as a direct reward for the selfless efforts of Yocheved and Miriam (the two midwives)? From a mystical dimension, Moses is perceived as a soul embracing all of Israel, i.e. our souls are "branches" of Moses' soul as per Isaiah 63,11 where Moses is equated with G'd's people Israel.

3According to Rashi who describes the "good" G'd did for the midwives as the houses G'd is reported to have provided for them as mentioned in the next verse, we could say that the Torah first had to mention that the people kept increasing as providing a caste of Priests as well as Royalty, would not make much sense unless there were a sufficient number of Israelites to warrant all this.