With the introduction of every new medication or drug there is a risk of certain unexpected negative reactions and side effects, same is the case with the introduction of pills for birth control. In the 1960's the birth control side effects of the pill included the instances of blurred vision, occasional nausea or weight gain but there were a few instances of blood clots and strokes that started to ring alarm bells. Birth control pills definitely were a great new innovation that helped women in preventing and controlling pregnancy but it wasn't of much use if it had side effects that were harmful to women.
Researchers and investigators scrambled to discover why there were such adverse effects and negative reactions and very soon they were successful in discovering two important reasons of such reactions. One reason was that if the levels of progesterone hormone was drastically reduced or replaced with progestin, the possibility of negative effects also dropped. Furthermore, researchers also concluded that there was a strong direct relation between the adverse effects of the pill and smoking habits of women, high blood pressure and other cardiovascular diseases. The risk and possibility of these side effects is higher for those women who smoke or have other cardiovascular diseases or have high blood pressure.
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