Hey there Hannah! I m sorry to hear about your loss, Trust me i have been there and i know how difficult it is for you to cope with this. There are many things that cause a miscarriage, first of all, is the excess weight, if you are overweight or even underweight it can affect your pregnancy a lot. The second cause is bad diet, always eating junk food or food full of oil or even fuzzy drinks can lead to a miscarriage. The third thing is doing drugs, drinking alcohol or smoking, this is one of the major factors behind a miscarriage. The fourth thing is Stress, When you are stressing yourself, you are also tiring your mind and body, which makes you both mentally and physically weak, and their strength is very important during Pregnancy. But don't lose hope hon! There are many ways to help you conceive after this, You can also get pregnant naturally tho, but if you fail at that, go for IVF. IVF is a very successful technique, my sister used it to conceive, i m sure it can help you too. Good Luck! Much Love!