One of the reasons postulated for Chrisianity becoming the state religion in Rome is that pagan Romans did not reproduce enough to maintain their population, in part because homosexuality was rampant, as was abortion and infantacide.
Christians and Jews cherished children. Christians rescued many children exposed to die by Romans. Christians and, to some extent, Jews were better at reproducing than Romans were, especially in Roman cities.
Wealthy Romans weren't necessarily inclined to have big families, and weren't typically love matches (arranged marriages, family alliances, upward mobility). Hadrian was one of the Adoptive Emperors, his mother didn't much like Trajan, and Hadrian and his wife didn't get along. He spent much of his reign touring the Empire. He regarded circumcision as mutiliation of the body, and disliked Jews a little more because of that.