I would consider starting by using a programme like Fitday.com to assess your total calorie intake each day and the macronutrient breakdown – perhaps increase your dietary fat intake a little using avocados, coconut, butter, or something similar and if you see no change in a few months play around with carb levels instead (more vegetables to increase your carb levels maybe?). Perhaps also assess your body fat percentage – is it particularly low now?

If you don’t see any improvements with that it may also be worth getting your doctor to check you out for another cause and also submitting a question to Robb Wolf for his Paleo Solution podcast. As I say, his clients/trainers seem to get pregnant with ease so I don’t think Paleo it the problem, perhaps moving to Paleo has just caused something else due to a change in dietary macronutrient ratios or total calorie intake (unless you assess your total food intake carefully any significant “diet” change, such as going low-carb or moving to some sort of special diet programme, can have a noticeable difference to your macronutrient ratios and calorie total too).

I hope this helps. I’d love to hear from you again with how it goes.

If you’ve cut your carbs right down (note, you won’t be zero carb unless you aren’t eating any vegetables either, but some veg are incredibly low carb) then you will find that you aren’t retaining water (in the not-quite-accurate summary, carbs increase glycogen stored in the muscles and glycogen retains water so carb depletion causes the body to hold less water and results in lower body weight). That can account for 2-3lbs water at the start of a low-carb diet, depending on how much muscle you are carrying, so don’t have any worries if people tell you you’ve lost “too much” weight too rapidly at the start! As you say – you feel great which is the important bit!

Several women have written to me and there seems to be a consistent pattern with lighter periods, no cramps or pain and often a much earlier bleed when they have been rigid with their paleo/primal diet so I would see it as your body settling down into a “new” pattern rather than something bad. However, I’m not a medical expert so if you are worried about anything then it is always worth getting it checked out – especially doing an over-the-counter pregnancy test if you’re worried you might be pregnant.

Best of luck with the continued progress and success!