Objective: The objective of this study was to compare outcomes of patients with prenatally versus postnatally diagnosed congenital abnormalities seen during the first 18 months of a recently established MFM unit.
Methods: Hospital charts of all congenital abnormalities diagnosed between July 2008 and December 2009 were reviewed. Data collected included: maternal demographics, perinatal outcome, neonatal mortality and morbidity as defined in the Radius trial.
Results: Fifty-five pregnancies with 57 anomalous fetuses were identified: 13 (23%) postnatally and 44 (77%) prenatally. Most frequent postnatally diagnosed anomalies were gastrointestinal (33%), central nervous system (CNS) (16%) and cardiac (16%); whereas prenatally diagnosed were CNS (29%) and genitourinary (23%). Mothers postnatally diagnosed had a 12 kg (17%) greater mean weight; 12 (92%) had anomaly scans reported as normal; birth weight and moderate neonatal morbidity were statistically greater (2.8 vs. 2.13 kg, p < 0.02) and (9/12 vs. 11/29, p < 0.03), respectively. Neonatal morbidity was 6.2 times more likely in the postnatally diagnosed group adjusting for birth weight, gestational age and route of delivery [OR (95% CI) 6.2, (1.2-32.4), p = 0.03].
Conclusions: Most abnormalities were diagnosed prenatally; however, the majority of postnatally diagnosed had false negative anomaly scans and experienced significantly more moderate neonatal morbidity.