Natural birth, breastfed for a day, but I was doubled over screaming in pain shortly after, so switched to every type of milk and formula for months after, no change. The pain continued every time I ate to varying degrees until I discovered peppermint oil when I was 30 years old. I think I contracted a HHV-6 infection in utero, and that caused a small cluster of nerves in my descending colon to develop nerve cells that registered pain when touched, so every time matter passed through it was excruciating. At least that was the theory of my last surgeon (he didn't blame the virus, but my mother's lack of self care while pregnant. Alcohol and drug abuse, smoking, and bulimia. It seems that led to my susceptibility to the virus). All my docs since have said that makes sense, the last one diagnosed me with HHV-6 and EBV, which completed the theory.