Fertile Trait not working

Product: The Sims 4
Platform:PC
Which language are you playing the game in? English
How often does the bug occur? Every time (100%)
What is your current game version number? 1.59.73.1020
What expansions, game packs, and stuff packs do you have installed? University, Island Living, Get Famous, Seasons, Cats and Dogs. City Living, Get Together, Get to Work, Outdoor retreat, Spa Day, and Parenthood
Steps: How can we find the bug ourselves? Play with sims who have the fertile trait from satisfaction points - I am not getting twins or triples.
What happens when the bug occurs? Both my sims - the husband and the wife have the fertile trait. I understand it only increases the odds, but in the pass I've always had twins or triples on the 2nd or third try. However - I keep having kid after kid and testing with other families and it is NOT working. What do you expect to see? I expect my sim to give births to triplets or twins in the same ratio to one baby births.
What do you expect to see? I expect my sim to give births to triplets or twins in the same ratio to one baby births. And yes I did the repair the game and it is updated.
Have you installed any customization with the game, e.g. Custom Content or Mods? Not now. I've removed them.
Did this issue appear after a specific patch or change you made to your system? No

‌

I am trying to complete the generations thing - so I keep playing kids born into families. Yes I did a cheat code to get satisfaction points and gave both sims the mom and the dad in three families now the fertile trait. 

IT NEVER WORKS 

Kid after kid is born single - no twins - no triples.

In the past when I played and my sims had the fertile trait every other kid turned out a triple or a twin! 

I WANT THIS BACK. 

Edit By Crinrict: Adjusted Tag