Survey of Risk Factors During Pre- and Post-Conception Periods in Mothers of Babies with Structural Birth Defects Seen at a Tertiary Hospital in Nigeria

Abstract

Background: Although some birth defects have a genetic origin, certain factors in the mother may have a direct effect on fetal development and increase the risk of having a baby with birth defect. Objectives: To assess the prevalence of risk factors during the pre- and post-conception periods in mothers of babies with birth defects at the University of Port Harcourt Teaching Hospital, Nigeria. Method: Data from an ongoing study on birth defects at the University of Port Harcourt Teaching Hospital were extracted for neonates seen from January 2006 to December 2011. Sociodemographic data and information on pre-and post-conception exposure of the mothers to risk factors were obtained using a semi-structured questionnaire. Each child was examined to describe the type and extent of defect(s). Results: Birth defect was identified in 501 (8.9%) out of 5,604 babies admitted within the study period. There were 273 (54.5%) males, 220 (43.9%) females and 8(1.6%) with indeterminate gender. The mean gestational age at delivery was 38.5±2.6 weeks and the mean birth weight was 2846±885g. The mean maternal age was 29.1±5.2 years with 412 (82.2%) being less than 35 years. The preconception and post conception risk factors identified include overweight/obesity 256 (51%), alcohol consumption 208 (41.5%), low socioeconomic status 217 (43.3%), non-medical abortion 245(34.7%), use of therapeutic drugs that are teratogenic (27.5%) and local herbs (23.8%). A hundred and twenty-six (17.8%) had a history of repeated miscarriages, 52 (10.4%) had hypertension while 20(4%) had diabetes. In 22 (4.4%) babies, there was a positive family history of a previous birth defect. Seventeen mothers (3.4%) had attempted unsuccessfully to terminate the index baby with birth defect using alcohol-based native herbs. In 198 (39.5%), no risk factors were documented. Conclusion: Overweight/obesity, low socioeconomic status and alcohol consumption pre- and post-conceptually appears to be major risk factors for the occurrence of birth defects in babies delivered to these rather young women in the Niger Delta. Maternal risk factors should be assessed in order to provide modifications during preconception care for a better pregnancy outcome.