Pregnancy is broken, it will not progress

I have my sim try for a baby, and even though the "take pregnancy test" action is still not available when I click on the toilet, I am able to tell if the pregnancy is successful by clicking on my sim, hovering over "go for a jog" in which case it says "sim can't do this while pregnant". However, after a few in game hours my sim is able to exercise again, and the pregnancy gets cancelled out and does not progress. In effect my sim cannot get pregnant at all.

I am not using CC or mods.