Maternal serum alpha-fetoprotein level and the relationship to ventriculomegaly in fetal neural tube defect: A retrospective cohort study

Objective: To estimate the significance of the association between mid-trimester maternal serum alpha-fetoprotein (MSAFP) level and fetal neuroanatomic findings in cases of open neural tube defect (ONTD). Methods: Retrospective study of patients referred for prenatal ONTD repair between 2012 and 2018. Cases were classified into three groups based on their MSAFP level: 1)High MSAFP (>3.8MoM - n = 22), 2) Moderately high MSAFP (<= 3.8 and >= 2.5MoM - n = 28), 3)Normal MSAFP (<2.5MoM - n = 18). MRI scans at the time of referral were used to assess the relationship between MSAFP and: A)Type of ONTD; B) Ventriculomegaly; C) Size of the myeloschisis lesion; D) Volume of myelomeningocele; E) Anatomical level of the lesion (LL). Results: Having a high MSAFP level was more likely to be associated ventriculomegaly at mid-gestation than a moderately high or normal MSAFP level (OR = 8.4;CI95[0.9-73.4];p = 0.05 and OR = 2.8;CI95[0.9-8.8];p = 0.07). There were no differences between the three groups regarding type of lesion, size of the myeloschisis lesion, anatomic LL, or volume of the myelomeningocele sac. Myeloschisis cases with normal MSAFP had a larger surface area when compared to myeloschisis cases with moderately high MSAFP (219.8 [104.4-551] vs 155.4[38.5-502.4] mm(2), p = 0.04). Conclusion: A 2nd trimester MSAFP level >3.8MoM in a fetus with ONTD is associated with mid-gestation ventriculomegaly. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

The study showed that a high MSAFP level in ONTD fetuses is associated with mid-gestation ventriculomegaly, while moderately high and normal MSAFP levels are less correlated. There were no significant differences between the groups in terms of lesion type, size of myeloschisis lesion, anatomical level, or volume of myelomeningocele sac. Myeloschisis cases with normal MSAFP had a larger surface area compared to those with moderately high MSAFP.