We are so sorry to hear of your pregnancy loss.
In general, when a woman has lost more than one pregnancy, it is important to investigate medically what is going on, as by seeing a high-risk pregnancy specialist. Unfortunately, as a woman ages, miscarriages are medically increasingly likely.
On a religious level, the traditional response would be for the couple to focus on tefillah and acts of chessed. These can be a source of both comfort and hope.
The Talmud does mention that it is dangerous for pregnant women to step over nail clippings. However, that does not mean that a woman will necessarily miscarry from doing so. It is possible that this is something that has changed over time.
Please write back with any further questions.