First-trimester maternal serum vitamin D and mode of delivery

Abstract

Low maternal vitamin D levels have been associated with adverse pregnancy outcome. A recent study has suggested that low maternal vitamin D levels at the time of delivery are also associated with an almost fourfold increase in caesarean section risk. The aim of the present study was to investigate whether there is a difference in maternal serum 25-hydroxyvitamin D (25(OH)D) levels at 11-13 weeks' gestation according to the mode of delivery. Maternal serum 25(OH)D levels were measured at 11-13 weeks' gestation in 995 singleton pregnancies resulting in the birth of phenotypically normal neonates at term. The measured 25(OH)D levels were adjusted for maternal age, BMI, racial origin, smoking, method of conception and season of blood testing, and the adjusted levels (multiple of the median; MoM) were compared between those who subsequently delivered vaginally and those that delivered by caesarean section. Delivery was vaginal in 79·6 % of cases, by emergency caesarean section in 11·6 % and by elective caesarean section in 8·8 %. The median 25(OH)D level in our population was 46·82 (interquartile range (IQR) 27·75-70·13) nmol/l. The adjusted maternal median 25(OH)D levels in the emergency and elective caesarean section groups (0·99, IQR 0·71-1·46 MoM and 0·96, IQR 0·73-1·27 MoM, respectively) were not significantly different from the vaginal delivery group (0·99, IQR 0·71-1·33 MoM; P¼ 0·53 and P¼0·81, respectively). First-trimester maternal serum 25(OH)D levels are similar between women who subsequently have a vaginal delivery and those who deliver by elective or emergency caesarean section. Key words: Vitamin D: Pregnancy: Caesarean section: Vaginal deliveryVitamin D has been implicated in the pathogenesis of CVD and diabetes mellitus (1,2) . Recent studies have also reported a link between maternal vitamin D deficiency and adverse pregnancy outcomes such as pre-eclampsia, gestational diabetes and small-for-gestational-age neonates (3 -5) .Vitamin D plays an important role in Ca homeostasis, bone mineralisation and muscle performance. The active metabolite of vitamin D, 1,25-dihydroxyvitamin D, binds to a vitamin Dspecific nuclear receptor in muscle tissue (6) , which leads to de novo protein synthesis, muscle cell growth (7) and improved muscle function (8) . A recent case-control study has reported that low maternal serum 25-hydroxyvitamin D (25(OH)D) concentration at the time of delivery was associated with an increased risk of caesarean section (emergency or elective) (9) , and this was attributed to the negative effect of vitamin D deficiency on muscle performance and uterine contractions.The aim of the present study was to assess further possible differences in maternal serum levels of 25(OH)D in the first trimester of pregnancy between women who subsequently have vaginal delivery compared with those who deliver by caesarean section. If vitamin D deficiency is associated with an increased risk of caesarean section due to suboptimal muscle function, this association would have been more marked in women...

Associations of maternal circulating 25‐hydroxyvitamin D3 concentration with pregnancy and birth outcomes

“…In one study conducted in Spain in 466 pregnant women, serum vitamin D in the first and third trimesters of pregnancy was not associated with a risk of caesarean section . In addition, a UK study among 995 women found no difference in maternal serum 25(OH)D concentrations between women with caesarean section and those with a vaginal delivery . We found a significant association between circulating 25(OH)D3 concentrations in pregnancy and risk of caesarean section due to failure to progress in labour, failed induction or cephalopelvic disproportion, but no association was found for other types of caesarean sections.…”

“…2 In addition, a UK study among 995 women found no difference in maternal serum 25(OH)D concentrations between women with caesarean section and those with a vaginal delivery. 42 We found a significant association between circulating 25(OH)D3 concentrations in pregnancy and risk of caesarean section due to failure to progress in labour, failed induction or cephalopelvic disproportion, but no association was found for other types of caesarean sections. These results suggest that the effects of vitamin D on skeletal smooth muscle performance and strength could be beneficial for a correct progress of labour.…”

The impact of vitamin D on the innate immune response to uropathogenic Escherichia coli during pregnancy

“…Interestingly, however, older pregnant women had higher levels than younger women, a finding in line with those of others [29]. Recent recommendations suggest that intake of up to 2000 IU/day of cholecalciferol may be required to achieve sufficient S-25-OHD levels during pregnancy [30].…”

Vitamin D Status and Related Factors in Newborns in Shanghai, China

“…VitD deficiency during pregnancy and early childhood leads to a variety of health problems for both the mother and the child [ 1 , 2 , 3 ]. Although VitD status during pregnancy has important implications regarding maternal complications, including decreased weight gain [ 4 ], gestational diabetes [ 5 ], preeclampsia [ 6 ], infections [ 7 ], and caesarean section [ 8 ], it may actually have more important implications for the general health of the developing fetus and newborn child. VitD deficiency in the newborn has been linked to hypocalcaemia, low birth weight, allergies, type I diabetes, impaired development, heart failure and rickets [ 9 , 10 , 11 ].…”