Arch Gynecol Obstet (2015) 292:3–4 DOI 10.1007/s00404-015-3716-z
REPLY
Reply to: The effect of seasonal variations on vitamin D levels in pregnant women Rimpi Singla1
Published online: 21 April 2015 Ó Springer-Verlag Berlin Heidelberg 2015
Sunlight, being the major source of vitamin D for all the populations across the globe, is bound to affect the prevalence of vitamin D deficiency in various geographical locations and also among the same population when measured in different parts of the year [1–3]. In our country, with abundant sunshine, skin exposure is minimal due to traditional clothing pattern. Also, there is tendency to avoid sun exposure by using sunscreens. Next important source is the diet. Our predominant vegetarian diet provides miniscule amount of vitamin D. In the absence of regular fortification of food items with vitamin D, we depend on sun exposure only for whatever vitamin D levels we have. Hence, the vitamin D deficiency is highly prevalent in India in spite of being sun-rich country. Previous studies have shown seasonal variation with higher levels of vitamin D during and at the end of the summer season. This has shown correlation with ankle strength and physical activity among old people, reflecting that outdoor activity is associated with increase in vitamin D [4]. Seasonal variation affects vitamin D status in subtropical regions too [1], but may not affect severely the deficient status of pregnant Indian women who otherwise have minimal sun exposure. We have not looked for seasonal variation in vitamin D levels in our study. Serum 25-OH vitamin D (inactive) form of vitamin D is the stable form of vitamin D and has been used as a This reply refers to the article available at doi:10.1007/s00404-015-3714-1. & Rimpi Singla [email protected] 1
Department of Obstetrics and Gynaecology, Post Graduate Institute of Medical Education and Research, Chandigarh, India
measure of vitamin D status in most of the clinical studies [5, 6]. Hence, this form was measured in this study as it allows for comparison across most of the studies in literature. Hyperparathyroidism is associated with preeclampsia. In a recent study, increase in PTH ([65 pg/ml) together with decrease in vitamin D was associated with preeclampsia. Alone increase in PTH or low vitamin D was not associated with preeclampsia [7]. Thus, hyperthyroidism may be an important but not the only underlying mechanism in the pathogenesis of preeclampsia. Vitamin D is an immunemodulatory secosteroid that helps in normal placentation [8, 9] and hence, prevention of preeclampsia and other pregnancy events associated with poor placentation like IUGR. Vitamin D deficiency is known to result in secondary hyperparathyroidism [10, 11]. There was high prevalence of vitamin D deficiency in our study population, with most of the women having severe deficiency. Hence, increased parathormone levels are expected in our population. Hence, we did not test for parathyroid hormone. Conflict of interest authors.
There is no conflict of interest among all the
References 1. Levis S, Gomez A, Jimenez C, Veras L, Ma F, Lai S, Hollis B, Roos BA (2005) Vitamin D deficiency and seasonal variation in an adult South Florida population. J Clin Endocrinol Metab 90:1557–1562 2. Gonza´lez-Parra E, Avila PJ, Mahillo-Ferna´ndez I, Lentisco C, Gracia C, Egido J et al (2012) High prevalence of winter 25-hydroxyvitamin D deficiency despite supplementation according to guidelines for hemodialysis patients. Clin Exp Nephrol 16:945–951
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Arch Gynecol Obstet (2015) 292:3–4 3. Chapuy MC, Preziosi P, Maamer M, Arnaud S, Galan P, Hercberg S, Meunier PJ (1997) Prevalence of vitamin D insufficiency in an adult normal population. Osteoporos Int 7:439–443 4. Bird ML, Hill KD, Robertson IK, Ball MJ, Pittaway J, Williams AD (2013) Serum [25(OH)D] status, ankle strength and activity show seasonal variation in older adults: relevance for winter falls in higher latitudes. Age Ageing 42:181–185 5. Bodnar LM, Simhan HN, Powers RW, Frank MP, Cooperstein E, Robert JM (2007) High prevalence of vitamin D insufficiency in black and white pregnant women residing in the northern United States and their neonates. J Nutr 137:447–452 6. Baker AM, Haeri S, Camargo CA Jr, Espinola JA, Stuebe AM (2010) A nested case–control study of midgestation vitamin D deficiency and risk of severe preeclampsia. J Clin Endocrinol Metab 95:5105–5109
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7. Scholl TO, Chen X, Stein TP (2013) Vitamin D, secondary hyperparathyroidism, and preeclampsia. Am J Clin Nutr 98:787–793 8. Evans KN, Bulmer JN, Kilby MD, Hewison M (2004) Vitamin D and placental-decidual function. J Soc Gynecol Investig 11:263–271 9. Evans KN, Nguyen L, Chan J, Innes BA, Bulmer JN, Kilby MD, Hewison M (2006) Effects of 25-hydroxyvitamin D3 and 1, 25-dihydroxyvitamin D3 on cytokine production by human decidual cells. Biol Reprod 75:816–822 10. Lips P, Wiersinga A, van Ginkel FC et al (1988) The effect of vitamin D supplementation on vitamin D status and parathyroid function in elderly subjects. J Clin Endocrinol Metab 67:644–650 11. Malabanan A, Veronikis IE, Holick MF (1998) Redefining vitamin D insufficiency. Lancet 351:805–806
REPLY
Reply to: The effect of seasonal variations on vitamin D levels in pregnant women Rimpi Singla1
Published online: 21 April 2015 Ó Springer-Verlag Berlin Heidelberg 2015
Sunlight, being the major source of vitamin D for all the populations across the globe, is bound to affect the prevalence of vitamin D deficiency in various geographical locations and also among the same population when measured in different parts of the year [1–3]. In our country, with abundant sunshine, skin exposure is minimal due to traditional clothing pattern. Also, there is tendency to avoid sun exposure by using sunscreens. Next important source is the diet. Our predominant vegetarian diet provides miniscule amount of vitamin D. In the absence of regular fortification of food items with vitamin D, we depend on sun exposure only for whatever vitamin D levels we have. Hence, the vitamin D deficiency is highly prevalent in India in spite of being sun-rich country. Previous studies have shown seasonal variation with higher levels of vitamin D during and at the end of the summer season. This has shown correlation with ankle strength and physical activity among old people, reflecting that outdoor activity is associated with increase in vitamin D [4]. Seasonal variation affects vitamin D status in subtropical regions too [1], but may not affect severely the deficient status of pregnant Indian women who otherwise have minimal sun exposure. We have not looked for seasonal variation in vitamin D levels in our study. Serum 25-OH vitamin D (inactive) form of vitamin D is the stable form of vitamin D and has been used as a This reply refers to the article available at doi:10.1007/s00404-015-3714-1. & Rimpi Singla [email protected] 1
Department of Obstetrics and Gynaecology, Post Graduate Institute of Medical Education and Research, Chandigarh, India
measure of vitamin D status in most of the clinical studies [5, 6]. Hence, this form was measured in this study as it allows for comparison across most of the studies in literature. Hyperparathyroidism is associated with preeclampsia. In a recent study, increase in PTH ([65 pg/ml) together with decrease in vitamin D was associated with preeclampsia. Alone increase in PTH or low vitamin D was not associated with preeclampsia [7]. Thus, hyperthyroidism may be an important but not the only underlying mechanism in the pathogenesis of preeclampsia. Vitamin D is an immunemodulatory secosteroid that helps in normal placentation [8, 9] and hence, prevention of preeclampsia and other pregnancy events associated with poor placentation like IUGR. Vitamin D deficiency is known to result in secondary hyperparathyroidism [10, 11]. There was high prevalence of vitamin D deficiency in our study population, with most of the women having severe deficiency. Hence, increased parathormone levels are expected in our population. Hence, we did not test for parathyroid hormone. Conflict of interest authors.
There is no conflict of interest among all the
References 1. Levis S, Gomez A, Jimenez C, Veras L, Ma F, Lai S, Hollis B, Roos BA (2005) Vitamin D deficiency and seasonal variation in an adult South Florida population. J Clin Endocrinol Metab 90:1557–1562 2. Gonza´lez-Parra E, Avila PJ, Mahillo-Ferna´ndez I, Lentisco C, Gracia C, Egido J et al (2012) High prevalence of winter 25-hydroxyvitamin D deficiency despite supplementation according to guidelines for hemodialysis patients. Clin Exp Nephrol 16:945–951
123
4
Arch Gynecol Obstet (2015) 292:3–4 3. Chapuy MC, Preziosi P, Maamer M, Arnaud S, Galan P, Hercberg S, Meunier PJ (1997) Prevalence of vitamin D insufficiency in an adult normal population. Osteoporos Int 7:439–443 4. Bird ML, Hill KD, Robertson IK, Ball MJ, Pittaway J, Williams AD (2013) Serum [25(OH)D] status, ankle strength and activity show seasonal variation in older adults: relevance for winter falls in higher latitudes. Age Ageing 42:181–185 5. Bodnar LM, Simhan HN, Powers RW, Frank MP, Cooperstein E, Robert JM (2007) High prevalence of vitamin D insufficiency in black and white pregnant women residing in the northern United States and their neonates. J Nutr 137:447–452 6. Baker AM, Haeri S, Camargo CA Jr, Espinola JA, Stuebe AM (2010) A nested case–control study of midgestation vitamin D deficiency and risk of severe preeclampsia. J Clin Endocrinol Metab 95:5105–5109
123
7. Scholl TO, Chen X, Stein TP (2013) Vitamin D, secondary hyperparathyroidism, and preeclampsia. Am J Clin Nutr 98:787–793 8. Evans KN, Bulmer JN, Kilby MD, Hewison M (2004) Vitamin D and placental-decidual function. J Soc Gynecol Investig 11:263–271 9. Evans KN, Nguyen L, Chan J, Innes BA, Bulmer JN, Kilby MD, Hewison M (2006) Effects of 25-hydroxyvitamin D3 and 1, 25-dihydroxyvitamin D3 on cytokine production by human decidual cells. Biol Reprod 75:816–822 10. Lips P, Wiersinga A, van Ginkel FC et al (1988) The effect of vitamin D supplementation on vitamin D status and parathyroid function in elderly subjects. J Clin Endocrinol Metab 67:644–650 11. Malabanan A, Veronikis IE, Holick MF (1998) Redefining vitamin D insufficiency. Lancet 351:805–806
