Comparing Neonatal Outcome Following the Use of Ondansetron versus Vitamin B6 in Pregnant Females with Morning Sickness: A Randomized Clinical Trial

Abstract

Background: Pregnancy-related nausea and vomiting or morning sickness with an overall prevalence rate of 80% is commonly appeared at the eighth week and frequently disappeared in most pregnant females at the 16th week of gestation. The severe form of the condition named hyperemesis occurs in one per 200 to 300 pregnancies; it is accompanied by dehydration, electrolyte instability and nutritional deficits and needs medical interventions. Limited data are available on harmful effects of common antiemetic medications used within pregnancy on human neonates. Objectives: The current study aimed to compare the effects of ondansetron and vitamin B6 on neonatal outcome in pregnant females with pregnancy-related nausea and vomiting. Neonatal outcome included the probable difference in neonates' gestational age, weight, height, head circumference and frequency of apparent congenital anomalies. Methods: This randomized double-blinded clinical trial was conducted on 188 primipara singleton pregnant females with pregnancy-related nausea and vomiting who referred to state healthcare centers of Zabol, Iran, in 2014. The pregnant females were randomly assigned to receive drug packages including ondansetron tablets (4 mg) or vitamin B6 tablets (40 mg) and patients were instructed to take one tablet twice daily. Females were followed up until delivery and neonatal outcomes including any congenital anomaly, weight, height and head circumference at birth were assessed. Results: There was no difference between the groups in the mean age of mother and the mean age of gestation. No differences were

Scientific opinion on the tolerable upper intake level for vitamin B6

“…One eligible intervention study was retrieved through the systematic search that assessed the effect of vitamin B6 supplementation on congenital anomalies (Shahraki et al, 2016). Shahraki et al (2016) conducted a randomised controlled trial (RCT) comparing the effect of ondansetron (n = 88), a serotonin 5-HT3 receptor antagonist, with PN-HCl supplementation (40 mg/ day vitamin B6, n = 100) in pregnant women suffering from nausea and vomiting. Supplementation was initiated between 4 and 16 weeks of gestation and women were followed-up until birth.…”

“…Two RCTs (Schuster et al, 1984;Shahraki et al, 2016), five prospective cohort studies (de Weerd et al, 2003;Lagiou et al, 2005;Shrim et al, 2006;Chen et al, 2015;McCullough et al, 2016) and one cross-sectional study (Chang, 1999) investigated the relationship between vitamin B6 exposure and birth weight and birth length and were initially considered pertinent. During the assessment, the biologically implausible range of PLP concentrations reported in the publication by McCullough et al (2016) was noted and this study was subsequently excluded from the evaluation.…”

“…One eligible intervention study was retrieved through the systematic search that assessed the effect of vitamin B6 supplementation on congenital anomalies (Shahraki et al., 2016 ).…”

“…Shahraki et al. ( 2016 ) conducted a randomised controlled trial (RCT) comparing the effect of ondansetron (n = 88), a serotonin 5‐HT3 receptor antagonist, with PN‐HCl supplementation (40 mg/day vitamin B6, n = 100) in pregnant women suffering from nausea and vomiting. Supplementation was initiated between 4 and 16 weeks of gestation and women were followed‐up until birth.…”

“…The Panel notes that the vitamin B6 intake in this study was within the range that is achieved by habitual diets, and it is unlikely that cases in this study can be attributed to the vitamin B6 intake of pregnant women, in particular as studies investigating higher vitamin B6 intakes have not observed an association. No congenital malformations occurred in an RCT in which pregnant women consumed 40 mg/day vitamin B6 as PN‐HCl or ondansetron from 4–16 gestational weeks onwards (Shahraki et al., 2016 ). Three case–control studies (Czeizel et al., 2004 ; Shaw et al., 2014 ; Goodman et al., 2019 ), among those one that included around 23,000 cases of congenital anomalies of all kind and 38,000 controls (Czeizel et al., 2004 ), did not show an increased risk of congenital malformations following vitamin B6 intakes of up to 60 mg/day.…”