Determinants and effects of fluid status changes in caesarean delivered neonates

Evidence suggests that caesarean section is associated with a reduced placental transfusion and poor iron-related haematological indices, both in cord and peripheral blood, compared with vaginal delivery. We assessed determinants and effects of fluid status changes on placental transfusion in neonates delivered by elective (ElCD) and emergency (EmCD) caesarean section.

Placental transfusion was estimated by ∆ haematocrit (Hct) increase from birth to 48 hours of life, accounting for contemporaneous ∆ body weight decrease, in 143 women/infant pairs, 62 who underwent ElCD and 81 EmCD, respectively.

Cord blood Hct levels at birth of ElCS neonates were significantly lower than those of EmCD neonates (44.58 + 4.87vs 49.93 + 4.29, P = .01). At 48 hours of life, capillary heel Hct levels of ElCD and of EmCD neonates were comparable. ElCD had a higher ∆ body weight decrease (ElCD -7.25 ± 1.74% vs EmCD -6.31 ± 2.34% [P: .011]) and ∆ Hct increase ([ElCD + 5.93 ± 4.92 vs EmCD + 3.59 ± 5.29, [P: .011]). In a linear regression model analysis, gestational age in ElCD neonates had a significant effect on the differences in arterial cord blood Hct, body weight at birth and body weight decrease at 48 hours after birth.

Early-term surgical delivery is a determinant of transient dilutional anaemia in ElCD neonates, lacking neuroendocrine response of labour and delivery.