I was the only child for both my mother and father. My mom did not like children, my dad did not care for them much either. They had other aspirations in life.
My mother's blood was very rare Rh factor negative, AB- or 4(VI)-, and my father's - positive, B+, as well as mine. That created dramatic pregnancy development expectations. Luckily, my red blood cells never crossed to my mother's organism, otherwise her immune system would have identified me as a foreign object and attack me. But her antibodies did not destroy my cells after all - she was very healthy, and it was her first pregnancy, so the risk was somewhat lower, and we both got lucky.
My mom was afraid of giving birth, but it was very quick and without complications.
The second pregnancy would have been higher risk, but I am almost sure they never considered having more kids.
The fact that I was a girl crushed my mother. She wanted a boy, only a son seemed to make it worthwhile for her. I did not know about it until I read my father's letter to her a few days after I was born. He was trying to convince her that having a girl was not that bad, and the letter was long. I was around 13 when I read it.
There was another letter from a later date as well, and all I can share with you from it, is that my parents' relationship was likely built on anything other than sexual passion, and that they were ready to part, and that she was unfaithful, and had entirely different plans for her life (this last piece was confirmed to me later by others).