The difference between the fictional Contraceptive Vaccine and the COVID vaccine's are significant. The first is that COVID can result in death or severe medical problems for the rest of your life. Secondly, while the vaccine will not protect you 100%, it has been shown to significantly reduce the symptoms and effects of contracting the disease. So in effect, you may still have a chance of getting COVID, but if you do, it will likely be a far less severe case. To my knowledge, pregnancy is binary so there is no comparison. Thirdly, getting the vaccine can help prevent you from spreading the disease to someone else. Pregnancy is not contagious.
If you don't believe in vaccines, that is your call, but do not spread false statistics.