B4227 - Age at menarche and adverse pregnancy outcomes - 21/12/2022
Previous evidence has shown that starting your period at an earlier age may increase your risk of having complications during pregnancy, such as a low birth weight baby. However, this evidence was all based on observations which may be skewed by the fact that having a higher BMI makes you more likely to start periods earlier and also increases your risk of these pregnancy complications. We will estimate the effect of having an earlier period on your risk of having complications during pregnancy association within ALSPAC. We will account for factors such as BMI and smoking, which have been collected in great detail for the volunteers participating in ALSPAC. This will then be compared to a separate approach to answer the same question, using a method called Mendelian randomization.