Could Weight Gain Be The Cause Of My Late Period, And Should I Lose Weight Before Trying To Conceive?

Hello, My periods are 23 days late at this point, and I m sure I m not pregnant. This is the first time my periods are so late. My periods are generally on time and on an average my cycle length is ~30 days. I don t know what s happening. I am 32 years old, and recently I have gained weight. I don t know if that s the reason. I am trying to lose it. Also, I want to get pregnant soon, but now I m worried that maybe there s something wrong and confused if I should lose weight before getting pregnant. But I will turn 33 in a couple of months, and I also feel under pressure because the biological clock is ticking. I don t have any other health condition that I know of. Please help! Thank you!