Preterm birth rates, measured as the number of babies born before reaching 37 weeks of gestation, have grown to virtually epidemic proportions in the U.S., accounting for 10 percent of all births during the year 2015. Preterm babies are much more likely to be impacted with cerebral palsy (CP) or other developmental disorders, among other serious conditions. Despite the strong correlation between low serum vitamin D levels in pregnant women and an increase in preterm birth rates, vitamin D testing is still not a standard testing procedure during pregnancy. Why would doctors avoid this simple, inexpensive test which could reduce the number of preterm births by as much as 50 percent?
Risks of Preterm Birth
Babies born before reaching 37 weeks of gestation are at a greater risk for developing any or all of the following:
- Breathing problems and/or challenges in feeding;
- Hearing and/or vision impairments;
- Cerebral palsy or other developmental delays.
Approximately one-third of all infant deaths are also a result of preterm birth, particularly those occurring before 32 gestational weeks. The emotional and financial impacts within the family are likely to be high and some believe that the critical bonding period between mother and baby is interrupted due to extended physical separation (preterm babies who undergo kangaroo methods of care are able to remain in contact with their mother, although this is not yet a standard medical practice).
Infections a Leading Cause of Preterm Birth
Uterine and/or placental infections are the primary cause of preterm labor, particularly in births that occur before 32 weeks of gestation and pose the greatest risk to the well being of the child. Such infections are difficult to diagnose and most women will experience no symptoms until their labor begins. Adequate vitamin D levels provide a level of protection against such infections by reducing any inflammation present in the uterus as well as directly killing the responsible bacterial cells. The mother’s entire immune system is also stimulated, allowing her body the increased opportunity to fight any low level infections which could harm her baby.
Screening Not Recommended Despite Strong Evidence of Risk
Despite the acknowledgement that vitamin D deficiency during pregnancy is common, the American Congress of Obstetricians and Gynecologists (ACOG) does not recommended routine screening of vitamin D levels for all women. Reasons cited include lack of sufficient evidence of importance, yet data has been available correlating low vitamin D levels to low birth weight, gestational diabetes and preeclamsia for years. A 2016 meta analysis clearly linked low vitamin D levels with a significant increase in the risk of preterm birth, and recommended all women maintain a minimum vitamin D serum level of 40 ng/mL to minimize risks. Despite the evidence, ACOG still maintains the position that the causes for preterm labor are largely unknown, although they do acknowledge a correlation with high blood pressure, alcohol, tobacco or other drug use, extreme stress, multiple fetuses, or a history of preterm birth during a previous pregnancy.
Certain Groups of Women at Greater Risk
Research clearly shows that women with darker skin pigmentation, those who eat a strictly vegetarian diet and who receive a limited amount of sun exposure are at the greatest risk of developing vitamin D deficiencies. The ACOG does recommend testing for at-risk groups, but does not recommend repeat testing to verify that the appropriate blood serum levels have been achieved through diet and supplementation. The ACOG states that ingesting standard prenatal vitamins and eating a diet containing fortified milk and juices will adequately raise vitamin D serum levels. Research, however, indicates otherwise, and repeated testing throughout pregnancy is the only way to verify the presence of a sufficient level of vitamin D to achieve an increased level of protection against preterm birth.
Vitamin D Testing is Inexpensive and Accurate
When considering the number of prenatal tests performed on the majority of pregnant women today, testing for blood serum levels of 25(OH) vitamin D concentration is one of the most inexpensive methods available to detect a highly correctable condition. Testing is considered highly accurate and can be completed frequently to verify that adequate levels of dietary supplements are being utilized. Current recommendations call for levels of vitamin D supplementation which are not likely to produce the clinician effects needed for preterm birth protection; testing would eliminate concerns regarding over supplementation while ensuring maximum benefits are achieved for the unborn child.
Parents Must Take an Active Role in Their Health Care
Parents to be can no longer depend on their medical care givers to provide adequate information to protect their unborn child. While it is unclear exactly why vitamin D testing is still not recommended throughout pregnancy, women may be able to request routine testing and adjust their levels of dietary supplementation until an ideal blood serum concentration is reached. If preterm birth does occur, testing of the mother’s vitamin D level immediately after giving birth may provide evidence that a deficiency was a factor in her early labor, assuming concentration levels are shown to be low. In such cases, a consultation with a skilled lawyer may prove beneficial in the recovery of damages resulting from negligent medical care.