Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Inclusion/Exclusion criteria
| Inclusion criteria | |
| - Birth weight < 1250 g | |
| Exclusion criteria | |
| - Structurally significant heart disease | |
| - Congenital anomalies of the respiratory tract | |
| - Eye malformations | |
| - Immunodeficiencies | |
| - Conception by in vitro fertilization |
