With the baby's arrival, they would have less time for just the two of them. But this could bring them closer in a different way. Spock might become more in touch with his emotions because of the baby, and Uhura would be more understanding of Spock's Vulcan side as they navigate parenting. For example, when the baby has a fever, Spock uses his Vulcan knowledge to try and cool the baby down, and Uhura is impressed by his calmness and resourcefulness.
The arrival of the baby would add a new layer of complexity to their relationship. They would need to communicate even more effectively. There might be disagreements about how to raise the baby, like whether to teach the baby more Vulcan or human values first. However, through these challenges, they would grow together. Spock would become more protective, and Uhura would be more patient. Their relationship would transform from just a romantic one to a family - centered one, with a new kind of bond formed through their shared love for their baby.