I know how you felt last year I went through the same urge wanting a baby. So you know what I did I bought myself a baby doll it really helped I felt soothed it then became something that was a comfort to me I felt safe with it then after that doll I felt I became stronger emotionally not needing validation and approval from others. I think the baby thing was more about me feeling sad and resistericted like I couldn't come in contact with my inner child and that was causing me emotional blockages within myself and relationships. It may sound strange but finding something you used as a child to comfort you can sometimes heal that craving for children. Like after I bought that doll I haven't thought about children and pregnancy since and plus it is just a comfort to me when I feel taken for granted for others. I think children can be very symbolic maybe your craving children because you feel like you are missing innocence in either yourself and the world and you want a child to reassure you that there is still lightheaded playfulness and innocence. Just another way i see it but honestly try hugging your favourite childhood toy maybe that will bring you the security you felt you've lost