Well, that you started on the 3rd every month is a bit of a coincidence because if you think about it, that means your cycle is not always the same number of days since some months are 30 days, some 31. We can all be late from time to time. It's pretty normal to be occasionally.
Tubal is meant to be permanent sterilization. However, yes. The clamps CAN come undone. Doesn't happen a lot. And it is important that if you suspect that that you go to the doctor and get checked. The rate of tubal pregnancies or ectopic pregnancies with pregnancy after tubal ligation is very high. So, clamp comes undone enough for sperm to enter but egg still gets fertilized in tube. This can be fatal to the mother. So, if you think you are pregnant, go to the doctor. Oh, and I guess a home test before that to see if it is positive would make sense. :>)
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