I have a similar situation now. I checked on my tribe this morning and found that there were 72 villagers. All but 3 females were over 50 and there were no children. Of course I immediately started an emergency repopulation program and managed to get 7 kids before the 3 moms were too old to make more little ones. As of this afternoon, the population is down to 44, and the youngest adult villager is 52. 3 of the kids are female, and I guess they're going to be busy when they grow up.

The population cap has created similar baby-boom situations in VV1, but it's definitely more likely in VV2 with the breeding-age limit.