It might be nothing but if your cycles continue to lengthen for no reason, see your GP for a referral to a gyno for some tests (or the GP could run the tests if he/she is confident in diagnosing and treating reproductive issues). It could be a hormonal imbalance or polycystic ovaries, you might not be ovulating every month for some reason.
Over the years my cycle lengths varied wildly. I'd be all over the place, then every 28 days for 2 years, then haywire again (longer and longer). I also used to have very variable pains which changed over the years, sometimes really heavy painful periods, sometimes painful ovulation, other times just general pain or no pain!! I wish I'd seen the Doc about it much sooner but i had just laughed it off for years and years. It took some time but a several issues were identified which were treatable. In the end we went the IVF route mainly because of 'my age' and endometriosis recurrence, but we certainly could have tried naturally for longer.
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