Table 2. Neonatal characteristics in the eligible OLIMPE study population, the included population and the included population still participating at 6 months corrected age.
| Eligible | Included | Included and followed-up at 6 months corrected age | |
|---|---|---|---|
| (N = 332) | (N = 174) | (n = 148) | |
| Characteristics at birth | |||
| Immediate postnatal transfer1 | 9.4 (6.7–13.1) | 6.5 (3.6–11.4) | 6.3 (3.3–11.7) |
| Gestational age | |||
| 24–26 weeks | 12.4 (9.5–15.9) | 9.7 (6.4–14.4) | 9.3 (5.9–14.5) |
| 27–31 weeks | 87.6 (84.1–90.5) | 90.3 (85.6–93.6) | 90.7 (85.5–94.1) |
| Gestational age, weeks | 28.9 (1.8) | 29.1 (1.8) | 29.1 (1.7) |
| Birthweight, g | 1199 (353) | 1194 (329) | 1198 (332) |
| Growth retardation, according to customized standard French curves [35] | 39.0 (33.6–44.7) | 40.0 (32.6–47.9) | 41.5 (33.4–50.0) |
| Gender, female | 47.8 (42.5–53.3) | 47.6 (40.2–55.1) | 49.3 (41.2–57.4) |
| Medical complications | |||
| HMD2 requiring surfactant | 50.8 (45.2–56.3) | 47.1 (39.7–54.6) | 47.6 (39.5–55.9) |
| Invasive mechanical ventilation | 67.5 (62.1–72.4) | 64.8 (57.2–71.7) | 63.9 (55.7–71.4) |
| Invasive mechanical ventilation duration, days | 3 (1–10) | 2 (1–5)** | 2 (1–5) |
| Severe bronchopulmonary dysplasia3 | 8.2 (5.7–11.7) | 3.5 (1.6–7.7)*** | 4.0 (1.8–8.8) |
| Neonatal antibiotics >3 days | 17.7 (13.1–23.5) | 18.5 (12.4–26.6) | 17.7 (11.3–26.6) |
| PDA4 treated (COI5 and/or surgery) | 22.2 (18.0–27.0) | 20.8 (15.4–27.5) | 20.5 (14.7–27.8) |
| Necrotizing enterocolitis | 5.1 (3.2–8.1) | 5.2 (2.7–9.8) | 4.9 (2.3–10.0) |
| Intraventricular haemorrhage6 | 29.3 (24.5–34.6) | 29.4 (22.9–37.0) | 28.5 (51.5–36.8) |
| Retinopathy of prematurity | 1.7 (0.8–3.8) | 1.8 (0.6–5.4) | 2.1 (0.7–6.3) |
| Abnormal auditory screening | 3.4 (1.9–6.0) | 1.2 (0.3–4.7)* | 0.7 (0.1–4.9) |
| Developmental care | |||
| Skin-to-skin (kangaroo) care | 70.1 (64.9–74.8) | 78.5 (71.7–83.9)*** | 78.8 (71.5–84.6) |
| Parental feeding support7 | 51.2 (45.7–56.7) | 56.1 (48.6–63.4) | 56.8 (48.6–64.7) |
| Breastfed at discharge | 43.6 (38.2–49.2) | 55.7 (48.1–63.1)*** | 56.0 (47.7–63.9) |
| Individualized DC program8 | 11.2 (8.2–15.2) | 15.1 (10.5–21.2)* | 16.4 (11.2–23.2) |
Data are weighted to take into account the different inclusion periods.
Data are means (standard deviation) or % (95% CI).
Invasive mechanical ventilation duration is presented as median, 25th percentile and 75th percentile for infants with invasive mechanical ventilation.
1Transfered to another institution in the first hours following birth;
2HMD: hyaline membrane disease;
3Defined as administration of oxygen for at least 28 days plus need for 30% or more supplementary oxygen and/or mechanical ventilatory support and/or continuous positive airway pressure at 36 weeks’ postmenstrual age;
4PDA: persistent ductus arteriosus;
5COI: cyclooxygenase inhibitor;
6Grade 1 or 2 intraventricular haemorrhage;
7Swaddling and/or sucking and/or skin-to-skin contact during a feed;
8DC: developmental care, i.e. NIDCAP or sensory motor program.
*p<0.05,
**p<0.01,
***p≤0.001 included vs non-included.