How can you have out-of-wedlock births without fornication, barring the death of a legitimate husband/father prior to the baby’s birth? Aside from that one special case, the one and the other are the same thing. All sin results in plague conditions.
They’re not exactly the same thing. Fornication is the sin and out of wedlock children are just one of the symptoms. There are many other harmful results from fornication such as males that refuse to mature in other areas of their life. Many of the young men wouldn’t turn to thuggery if most of the ladies insisted on a ring and a job before they put out.