I'm saying once a child arrives, it's expected and totally fine that women give less attention to their spouses and their relationships with those spouses. The moment a child is born, the parents' main objective is keeping that baby alive, which involves a woman being next to her child literally 24/7, especially since that baby needs to eat every few hours and he/she also poops every few hours too. This translates into the mom being barely able to function the rest of the time, so not only she won't be paying a lot of attention to her partner, but she won't be taking proper care of herself either.
Now, when the child moves on to a formula and doesn't need the mom's presence as often anymore, this is when women usually go back to focusing on themselves and their partners. However, there is a huge problem. Most men don't strive to do 50% of the work even outside their 9-to-5s. Considering how many men barely know how to change a diaper, when the child ate formula last time, how to dress the toddler in the morning, what that child wore yesterday, their children's teachers' names, when the next PTO meaning is; this is the main reason some women have much less time to pay attention to their spouses. The good news is, I've seen women who have excellent partners who do all the work they can and often not only do 50% of childcare after their job but tell their wives to go relax for a bit and take care of their kids on their own. My father is one of those men. And I can attest to women paying A LOT of attention to their relationships and husbands, and even MORE attention to them when they have a proper partner who's a good husband. I think my mom fell in love with my dad even more when she saw how great he is with me, how much childcare he does every chance he gets, and how he doesn't use work as an excuse not to go home and take care of me.
The sad reality is, that quite a few men say they want children and then do 10% of the work. Those are people who are unfit to be partners, husbands and especially fathers. And sometimes, those guys are so horrendous at being fathers they also whine about their wives not paying as much attention to them after giving birth; while the truth is, this is the result of their lack of interest in being good partners and fathers. I've observed a lot of such men, and I'm truly sorry for their children and wives (who should consider becoming ex-wives).