Yes - just a simple blood test and your DH can be tested for it too. My DH has it and it meant that both he and I were on MegaFolate for three months before starting TTC. I am still on it of course as now in early pregnancy.
The Dr will be looking for a "Folate Reductase Disorder" there are two types of the disorder, turns out I have one type and DH has the other! You can test for it at any time in your cycle so go for it!
Firstly, I'm so sorry for your heartbreaking experiences. To lose a child is a terrible thing.
Secondly, suggesting running straight out is a bit of a big ask, and as you say, 20E chests don't really go well with running. But yes, losing weight can help you to become pregnant and avoid complications - even if the problem with your pregnancies is caused by something else, it's good to be less overweight to help with delivery complications. Not news to you I know. Have you spoken to a physiotherapist about a suitable exercise regime though? You might be able to agree on a program which fits your body shape, your current fitness level and what fits in with your lifestyle and motivation. I am a physiotherapist and we run clinical pilates which is a special form of pilates done by physios which takes into account your medical issues and is designed to build your endurance and muscle control. I have had quite a few people lose weight doing this which wasn't their initial aim, but they are feeling healthier and fitter and one is 16kg lighter now than when she started. It's very relaxed and controlled and there's no bouncing around etc like aerobic classes.
Perhaps if you find a physiotherapist who does clinical pilates, or one who specialises in womens health (especially pregnancy) that might help re weight.
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