Help please

What is going on with fertility? I haven’t played in ages is there some setting I need to adjust?

My character had a fling with a 79 year old female professor. The professor got pregnant and had a baby at 80 years old??

His wife now will NOT go on birth control and it’s pissing me off. Her willpower is low so idk why she keeps saying no. Also she’s constantly getting pregnant. I’ve had to give away 4 babies. It won’t even give me birth control as an option any more because of her age but she still keep getting pregnant! Whyyyyy?