“HOW DID WE ARRIVE AT A WORLDWIDE EPIDEMIC OF VITAMIN D DEFICIENCY?”
ROBERT L. BARBIERI, MD (EDITORIAL; JUNE 2010)
Vitamin D is vital for the developing fetus
I appreciated Dr. Barbieri’s editorial on vitamin D deficiency. Most obstetricians do not realize the consequences of vitamin D deficiency for the developing fetus and newborn. The maternal vitamin D level has an effect on fetal acquisition of bone mineral in utero.
Mother–offspring cohort studies have shown that vitamin D insufficiency has a detrimental effect on bone mineral accrual by the fetus, leading to reduced bone mass at birth and in childhood.1 Vitamin D deficiency can cause growth retardation and skeletal deformities and may increase the risk of hip fracture in later life.2
Childhood rickets has reemerged due to vitamin D deficiency in mothers during pregnancy. Fetal stores of vitamin D depend entirely on maternal supply. Most prenatal vitamins contain only 400 IU of vitamin D daily. This amount may not be sufficient for both mother and developing fetus.
Milk from breastfeeding mothers provides little vitamin D. Women who are deficient in this nutrient provide even less.
Vitamin D also plays an important role in glucose metabolism. Vitamin D deficiency increases insulin resistance and decreases insulin production.2 Increasing the intake of vitamin D during pregnancy reduces the development of islet antibodies in the offspring, which may, in turn, reduce the incidence of diabetes in the offspring.3 One study demonstrated that a daily intake of 1,200 mg of calcium and 800 IU of vitamin D lowered the risk of type 2 diabetes in women by 33%.4
When ordering a prenatal blood test profile, it is important to include assessment of 25-hydroxyvitamin D to determine which patients require supplementation to prevent detrimental fetal effects.
Frank Bonura, MD
Director, Department of ObGyn and Osteoporosis Program
St. Catherine of Siena Medical Center
Dr. Barbieri responds: Measure the maternal vitamin D level
I wholeheartedly agree with Dr. Bonura’s important advice. As obstetricians, we can improve the health of the mother and newborn by measuring maternal 25-hydroxyvitamin D levels and prescribing adequate amounts of vitamin D.
Who would have thought that vitamin deficiency would be a continuing public health problem in 2010?
“CAN WE REDUCE THE RATE OF SCHEDULED BIRTHS THAT OCCUR
EARLIER THAN 39 WEEKS OF GESTATION?”
GEORGE A. MACONES, MD (EXAMINING THE EVIDENCE; JUNE 2010)
Early scheduled births are fueled, in part, by complacency and greed
Yes, we can increase the number of births that occur closer to term, but it will take time and effort.
First, we must address and dispel a few myths. Not long ago, even maternal-fetal medicine specialists, who should know better, stopped trying to prolong pregnancies beyond 32 weeks. Their attitude was: “That baby will survive—why bother?”
Second, NICUs generate handsome revenue by caring for preemies—and many hospitals have taken notice!
I put myself in hot water with hospitals and a colleague by promoting term deliveries. We really need to consider our responsibility to surpass “do no harm.” Rather, we need to ask: “Are we helping our patients—or just ourselves?”
Stefan Semchyshyn, MD, MBA
“New culture” of obstetrics isn’t so great
There has been a great outcry to reduce cesarean births (for good reason, to my mind). I believe that a significant number of early scheduled births have contributed to the rise in the rate of cesarean delivery. I believe that we are experiencing a “new culture” of obstetrics: “I can do it, therefore, I will.” God forbid that an OB should wait until the patient goes into labor and he or she has to get up in the middle of the night to take care of her.
Robert S. Ellison, MD
W. Covina, Calif