Maternal serum alpha fetoprotein among pregnant females in Alexandria.
Maternal serum alpha fetoprotein (MSAFP) was introduced as a screening test for congenital malformations especially neural tube defects (NTDs) two decades ago. However, many factors were known to affect its level. From these are racial differences and maternal weight. The aim of the present work is to illustrate the normal distribution of MSAFP among working pregnant women in Alexandria in gestational age 16-18 weeks, to identify some of its determinants, and to determine the specificity and sensitivity of MSAFP for the detection of congenital anomalies and adverse pregnancy outcome.


METHODS
A sample of 608 pregnant working women who were 16-18 week gestation was recruited for the study from the antenatal clinic affiliated to Gamal Abdel Nasser Health Insurance Hospital in Alexandria. The enrolled women were interviewed using a structured questionnaire and a blood sample was collected from each of them to measure the level of MSAFP. At the expected time of delivery, Gamal Abd el Nasser Health Insurance Hospital was visited to collect data about the outcome of pregnancy of the enrolled women.


RESULTS
The median of MSAFP level for deliveries with no congenital anomalies were 25.5, 33.5, and 53.2 IU/ml, at gestational weeks 16, 17 and 18 respectively. The significant variables related positively to MSAFP level included abortion or stillbirth, congenital anomalies in the index pregnancy, gestational age, bleeding during pregnancy, gestational diabetes, twin pregnancy, consanguinity between maternal parents, history of congenital or genetic diseases in maternal family, and caesarian section deliveries. Fatigue score was negatively correlated to MSAFP level. Using MSAFP multiples of median (MOM), 42.9 % of abortions and stillbirths, 57.1 % of twin pregnancies, 31.25 % of preterm deliveries and 27.3 % of low birth weight had levels of 3 MOM or more. One fourth of the congenital anomalies were below 0.5 MOM and 41.7 % were at or above 3 MOM. The sensitivity of MSAFP test for the detection of NTDs (cutoff point 2.5+ MOM) or Down syndrome (cutoff point <0.5 MOM) among the study sample was 100% (CI: 19.8-100%). Specificity for NTDs was 92.7% (CI: 90.3-94.6%), while the specificity for Down syndrome was 89.1% (86.3-91.4%). The sensitivity for adverse pregnancy outcome (cutoff point <0.5 or 2.5+ MOM) was 41.6, and the specificity was 85.8%. In conclusion, the cutoff points of MSAFP of the study sample are different from those for other populations. Different factors affect the level of MSAFP including adverse pregnancy outcomes. It is recommended to introduce antenatal screening for congenital anomalies as a routine screening test during pregnancy using levels adapted from the local population for cutoff point determination.
Baghagho
Ehssan E
EE
Family Health Department, High Institute of Public Health, Alexandria University.
Kharboush
Ibrahim F
IF
El-Kaffash
Dalal M
DM
KarKour
Tarek A
TA
Ismail
Suzan R
SR
Mortada
Mona M
MM
D000328:Adult; D004534:Egypt; D005260:Female; D005865:Gestational Age; D006801:Humans; D007407:Interviews as Topic; D009436:Neural Tube Defects / Q000097:blood / Q000175:diagnosis; D011247:Pregnancy; D011296:Prenatal Diagnosis; D000509:alpha-Fetoproteins / Q000032:analysis*
D000509:alpha-Fetoproteins