The fact that most MAs on results from RCTs did not show a beneficial effect does not disprove the hypothesis suggested by observational findings on adverse health outcomes of low 25OHD levels
Background A large number of observational studies have reported harmful effects of low 25-hydroxyvitamin D ( 25OHD ) levels on non-skeletal outcomes .
We performed a systematic quantitative review on characteristics of r and omized clinical trials ( RCTs ) included in meta-analyses ( MAs ) on non-skeletal effects of vitamin D supplementation .
Obstetric and neonatal outcomes of maternal vitamin D supplementation: results of an open-label, randomized controlled trial of antenatal vitamin D supplementation in Pakistani women.
OBJECTIVE The objective of the study was to determine whether vitamin D ( vitD ) supplementation during pregnancy affects obstetric and neonatal outcomes . SETTING The study was conducted at a university hospital in Karachi , Pakistan . METHODS The study was a single-center , open-label , r and omized , controlled trial of routine care ( group A , 200 mg ferrous sulfate and 600 mg calcium daily ) vs vitD supplementation ( group B , 4000 IU vitamin D3 daily ) , started at 20 weeks and continued till delivery . Maternal serum sample s of 25-hydroxyvitamin D ( 25OHD ) were collected at baseline and delivery . Neonatal vitD status was assessed in cord blood or in neonatal serum sample s within 48 hours of birth . Obstetric outcomes included gestational hypertension , gestational diabetes , and preterm labor , and neonatal well-being included small for gestational age , birth weight , length , head circumference , and 1- and 5-minute Apgar scores . RESULTS Of 207 gravidae enrolled , 193 completed the trial .  Maternal age , vitD status , and gestational age at enrollment were comparable between the two groups . At delivery , maternal 25OHD was increased in group B ( 18.3 ± 11 ng/dL vs 8.82 ± 11.84 ng/dL ( P = .001 ) compared with group A ( 6.9 ± 7.0 ng/dL vs 6.32 ± 3.97 ng/dL , P = .06 ) . The obstetric outcomes were comparable between the two groups ( P > .05 ) . Neonatal 25OHD levels were significantly higher in group B compared with group A ( 19.22 ± 12.19 ng/dL vs 6.27 ± 5.2 ng/dL ) . There was positive correlation between maternal and neonatal 25OHD levels ( r = 0.83 , P = .001 ) . One- and 5-minute Apgar scores were significantly higher in group B ( 7.10 ± 0.66 vs 6.90 ± 0.50 , P = .026 , and 8.53 ± 0.68 vs 8.33 ± 0.81 , P = .051 , respectively ) . Neonatal anthropometric parameters were comparable between the two groups ( P > .05 ) . CONCLUSION Maternal vitD supplementation improved maternal and neonatal vitD status
The fact that most MAs on results from RCTs did not show a beneficial effect does not disprove the hypothesis suggested by observational findings on adverse health outcomes of low 25OHD levels
Background A large number of observational studies have reported harmful effects of low 25-hydroxyvitamin D ( 25OHD ) levels on non-skeletal outcomes .
We performed a systematic quantitative review on characteristics of r and omized clinical trials ( RCTs ) included in meta-analyses ( MAs ) on non-skeletal effects of vitamin D supplementation .