We must be reading different articles.

neonatal means less than four weeks after birth. NOT before birth.

Galiniera et al. (2008):
the article DOES state that surgey takes place days after birth.
FROM THE VERY FIRST LINES OF THE ABSTRACT:

Results: Sixty-one newborns, 20 girls and 41 boys, aged 7.5 ± 6.7 days were operated on.

That's between six and seven days. I'm not sure how that can be interpreted any other way.

E. FREEDLANDER, (1990)

Operation was usually carried out within cases the first 48 hours of life.

From the Murray article:

Although repair is generally performed around
3–4 months postpartum in the UK, in the past two
decades some centres have conducted neonatal
repair. Surgical outcome appears unaffected by this
difference in timing (Goodacre, Hentges, Moss,
Short, & Murray, 2004);