Von Williebrands disease does not stop you from getting pregnant. Yes bleeding can be more during delivery or during menses because of less capability of blood to clot. But as the age increases the quality of eggs (Ovum) starts decreasing and less chance of getting pregnant. there is also hormonal lag along with body weight and other things leads to menstrual cycle and as you have irregular menses there is chance that they are disturbed. You have to loose weight. and get a consultation done with infertologist. he will guide you properly after examination and history. On a base line you should do haemogram, Prolactin, Blood sugar level, Insulin level, Thyroid level. And one Pelvic sonography. Some tests may required afterward. Do one semen analysis report of your husband also. It is also to be normal for getting pregnant.