1. Vitamin D deficiency in pregnant women and newborn
A Sachan
Asst Professor, Dept of Endocrinology
SVIMS, Tirupati
Good afternoon everybody, I am presenting my data on vitamin D deficiency in north Indian pregnant women and their newborns. This study was conducted at the Sanjay Gandhi postgraduate Institute of medical sciences and Queen Mary’s hospital, Lucknow, India.

2. Introduction
Vitamin D deficiency unexpected in a tropical country with abundant sunshine.
Hypovitaminosis D resulting in severe osteomalacia in adolescents has been observed
Natl Med J India 2003;16:139-42
We know that pregnancy is associated with increased demand of calcium and subclinical deficiency can become overt during pregnancy. Despite abundant sunshine we have demonstrated hypovitaminosis D in adolescence, a high risk group for vitamin D deficeincy. Possible contributory factors being poor outdoor activity and traditional clothing, leading to poor sun exposure. Calcium deficiency per se can cause secondary hypovitaminosis D.

3. Introduction Possible contributory factors:
Poor outdoor activity / sun exposure / traditional clothing
Air pollution
Skin pigmentation

4. Introduction
Milk and milk products, the source of calcium, are expensive in India
Deficient calcium intake results in childhood rickets and adolescent osteomalacia with healing on dietary calcium replenishment
J Trop Pediatr 2003;49:201-6
Arch Dis Child 2003;88:812–7
N Engl J Med 1999;341:563– 8
Calcium supplementation is a standard practice in antenatal clinics in urban area of India, but not in rural area.
Natural sources of calcium, like milk and milk products, are prohobitively expensive in India.
Routine vitamin D supplementation and fortification is not practised in India, however rural women tend to get more sun exposure due to extensive outdoor activity.

5. Introduction Experimental study in a rat model
Calcium deficiency   PTH   1,25(OH)2D   conversion of vitamin D to polar metabolites in liver  vitamin D deficiency
Calcium replenishment   vitamin D
Nature 1987;325:62-65

6. Introduction
Active trans-placental transport of calcium to the developing fetus during pregnancy
Hypovitaminosis D during pregnancy
fetal hypovitaminosis D
neonatal rickets and tetany
infantile rickets
Infantile rickets is associated with high prevalence of lower respiratory tract infections, the largest cause of infant mortality

7. Introduction ↓ whole-body and lumbar-spine BMCin children
Lancet 2006;367:36-43

8. Introduction Other effects on neonates ↑ risk of bronchial asthma
Am J Clin Nutr 2007;85:853-9
Diabetes related autoimmunity
Pediatr Diabetes 2007;8:11-4
↓ length at birth and 1-min Apgar
Gynecol Endocrinol 2006;22:585-9

9. Aims
to determine the prevalence of clinical or biochemical osteomalacia & maternal & fetal hypovitaminosis D among urban and rural north Indian women
and to study the correlation of those prevalences with calcium intake, sun exposure, serum 25(OH)D, and plasma intact parathyroid hormone (PTH)
Aims of the present study were to study the prevalence of hypovitaminosis D among pregnant women and to correlate vitamin D status with sun exposure, daily calcium (dietary plus supplemental) intake, serum intact parathormone (iPTH), and neonates’ serum 25(OH)D.

10. Material and Methods Subjects:
all women with full-term live pregnancy presenting to the hospital and their infants
Recruitment from Sept to Nov
Exclusion criteria
Chronic liver disease
Renal disease
Treatment with antitubercular drugs
Treatment with antiepileptic drugs

11. Material and Methods Registered 207 subjects out of 572 women
157 Hindu
50 Muslim
29 women practiced purdah

12. Material and Methods Obstetric / dietary / sun exposure history
Any complaints s/o osteomalacia
Physical examination of all subjects
Daily calcium & vitamin D intake:
Dietary calcium & vitamin D intake (food frequency questionnaire)
Supplemental calcium intake
Detailed dietary and sunexposure history was asked of each subject and physical examination was performed.
Daily calcium intake was calculated as the sum of dietary calcium intake and daily supplemental calcium intake. Dietary calcium intake was assessed with a food frequency questionnaire

13. Material and Methods Daily sun exposure over winter and summer months*
Expressed as hours of exposure per day X body surface area exposed
Daily sun exposure was assessed separately over winter and summer months and expressed as sun exposure per day in minutes, while exposing face and both forearms
Neonatal anthropometry of babies born to the subjects was also performed

14. Material and Methods Maternal peripheral venous sample
Heat labile alkaline phosphatase (HLAP)*
25-hydroxyvitamin D {25(OH)D}
Total serum calcium (Ca)
corrected for albumin, if < 4 gm / dl
Inorganic phosphorus (iP)
intact parathormone (iPTH) (n=157)
*HLAP = total SAP - heat stable SAP (56oC for 15 min)
Peripheral venous samples were collected from each subject and were analysed for serum heat labile alkaline phosphatase, 25-hydroxyvitamin D, total serum calcium and inorganic phosphorus (iP). Serum albumin was also analysed and if found low (below 4 gm/dl), total calcium was corrected for albumin. Anticoagulated blood was collected on ice for plasma intact parathormone (iPTH).

15. Material and Methods Cord blood sample (n=117)
serum alkaline phosphatase (SAP)
25(OH)D
Upper limit of normal for HLAP <125 U/L, Cord blood SAP <165 U/L
Cord blood samples were collected from neonates born to subjects and were analysed for serum alkaline phosphatase and 25(OH)D. Upper limit of normal for heat labile alkaline phosphatase being 125 U/L and 165 U/L for cord blood.

16. Material and Methods Serum Ca, Albumin, iP, SAP/HLAP:
Spectrophotometry
25(OH)D:
RIA (Diasorin)
iPTH
IRMA (DSL)

17. Statistical analysis SPSS for windows, release 9.0
Comparison of proportions: 2 test
Data log transformed, means compared with Student’s t test
Correlation coefficient: Spearman coefficient
Cut off of 25(OH)D: Linear regression analysis
Two tailed significance level: 0.05
Statistical analysis was done using SPSS software.

18. Results Registered and not registered subjects
Registered Not registered
(n= 207) (n 365)
Age (y) 24.0 5.1
Weight (kg) 55.1 4.3
Parity 1.1 1.12*
Birth weight (kg) 2.9 2.02*
Hindu/Muslim 157/ /98
* P<0.001 (Student’s t test)

19. Results No subject had clinical e/o osteomalacia
Biochemical osteomalacia in 29 (14%) subjects

20. Sub with & without biochemical osteomalacia (HLAP>125)
Subjects with Subjects without
osteomalacia(n=29) osteomalacia (n=178)
Ca (mg/dL) 9.4± ±0.7
iP (mg/dL) 3.6± ±1.73*
25(OH)D 12.1± ±9.5
(ng/mL)
Maternal 26 (89.7) 148 (83.1)
hypovitaminosis D {25(OH)D < 22.5 ng/ml}
iPTH (pg/mL) 127±180(n=24) 74±897(n=133)**
*p<0.05
**P<0.005

21. Sub with & without biochemical osteomalacia (HLAP>125)
Subjects with Subjects without
osteomalacia(n=29) osteomalacia (n=178)
Cord blood 8.1± ±5.4
25(OH)D (ng/mL)
Daily calcium 813± ±466
intake (mg/d)
Daily calcium 22 (75.8) 138 (77.5)
intake<RDA
Sun exposure 4.9± ±6.0
score over past 3 mo (h/d X % BSA exposed)

22. Results Subjects with Subjects with 25(OH)D<10ng/ml 25(OH)D>10
(n=88, 42.5%) ng/ml
iPTH 125± ±39
(pg/ml) P<0.001
Cord blood 5.2± ±5.9
25(OH)D (ng/ml) P<0.001
Out of 207 subjects 68 were rural and 139 were urban and iPTH was available in 157 of them. 117 cord blood samples were analysed. A large number of subjects had hypovitaminosis D. 42% of the subjects and 72 % of the neonates had low vitamin D levels, while alkaline phosphatase was elevated in 14% of the subjects and 14% the babies. 77% of the subjects had daily calcium intake which was less than the recommended daily intake of 1200 mg / day.

23. Results Correlations Maternal 25(OH)D with cord blood 25(OH)D
r= 0.79, P<0.001
Maternal 25(OH)D with iPTH
r= -0.35, P<0.001
HLAP with cord blood AP
r= 0.19, P<0.05

24. Correlation: maternal 25(OH)D with iPTH

25. Results Regression equation: Linear regression equation:
iPTH= [-3.32 X 25(OH)D]
Cutoff of 25(OH)D= 22.5 ng/ml
Number of subjects with 25(OH)D <22.5 ng/ml: 174 (84%)

26. Results: Comparison of urban and rural subjects
Urban Rural p (n=140) (n=67)
Sun exposure
3 months 4.1   8.1 <0.001
1 year 7.5  
Calcium intake
(mg/day) 842   404 <0.001

27. Results: Comparison of urban and rural subjects
Urban Rural p (n=140) (n=67)
Calcium intake 101 (72%) 59 (88%) <0.05
<RDA (1200 mg/day)
Vit D intake 16.4   7.6 NS
(IU/day)
HLAP (U/L) 87   31 NS

28. Results: Comparison of urban and rural subjects
Urban Rural p (n=140) (n=67)
Osteomalacia 24 (17%) 5 (7%) NS
(HLAP > 125 U/L)
25(OH)D (ng/ml)   8.9 NS
Hypovitaminosis D 118 (84%) 56 (84%) NS
{25(OH)D < 22.5 ng/ml}
iPTH (pg/ml) 94   49 NS

29. Results
Total daily calcium intake, HLAP, 25(OH)D, and iPTH did not differ between subjects practicing purdah and those not practicing purdah

30. Results Neonates’ mean cord blood 25(OH)D: 8.45.7 ng/ml
112/117 (96%) neonates were vitamin D deficient
No difference in AP between babies born to mothers with normal or low 25(OH)D

32. Other studies on Asian pregnant subjects
Authors Subjects N 25(OH)D (ng/ml)
Goswami Indian (Delhi) 4.3
Heckmatt Asian (U.K.) 1.3
Brunvand Pakistani
Atiq Pakistani 9.0

33. Summary High prevalence of hypovitaminosis D in pregnant women.
Correlation of 25(OH)D with iPTH suggests physiological relevance.
Fetal vitamin D levels mirror maternal hypovitaminosis D, and fetal hypovitaminosis is common, assuming public health importance.
On summarising hypovitaminosis D was common in both urban and rural subjects living in a tropical country. A significant correlation of 25(OH)D with iPTH suggests physiological relevance. Fetal vitamin D levels mirror maternal hypovitaminosis D, and fetal hypovitaminosis is common.

34. Summary...
Vitamin D deficiency equally common among urban and rural subjects, despite rural subjects having better sun exposure
Possible contributing factors
Urban: low sun exposure
Rural: low calcium intake
Dark skin less efficient in making vitamin D?
Possible contributory factors for hypovitaminosis D can be low sun exposure due to traditional clothing practices, avoidance of sun exposure and dark skin in urban subjects and low calcium intake for the rural subjects.

35. Future Directions Effect on neonatal calcium metabolism S. calcium
iPTH

36. Thank You