Maternal obesity and risk of preterm delivery.
JAMA. 2013 Jun 12;309(22):2362-70. doi: 10.1001/jama.2013.6295.
Cnattingius S, Villamor E, Johansson S, Edstedt Bonamy AK, Persson M, Wikström AK, Granath F.
Clinical Epidemiology Unit, T2, Department of Medicine Solna, Karolinska University Hospital, Karolinska Institutet, SE-171 76 Stockholm, Sweden. sven.cnattingius at ki.se
IMPORTANCE: Preterm birth is a leading cause of infant mortality, morbidity, and long-term disability, and these risks increase with decreasing gestational age. Obesity increases the risk of preterm delivery, but the associations between overweight and obesity and subtypes of preterm delivery are not clear.
OBJECTIVE: To study the associations between early pregnancy body mass index (BMI) and risk of preterm delivery by gestational age and by precursors of preterm delivery.
DESIGN, SETTING, AND PARTICIPANTS: Population-based cohort study of women with live singleton births in Sweden from 1992 through 2010. Maternal and pregnancy characteristics were obtained from the nationwide Swedish Medical Birth Register.
MAIN OUTCOMES AND MEASURES: Risks of preterm deliveries (extremely, 22-27 weeks; very, 28-31 weeks; and moderately, 32-36 weeks). These outcomes were further characterized as spontaneous (related to preterm contractions or preterm premature rupture of membranes) and medically indicated preterm delivery (cesarean delivery before onset of labor or induced onset of labor). Risk estimates were adjusted for maternal age, parity, smoking, education, height, mother's country of birth, and year of delivery.
RESULTS: Among 1,599,551 deliveries with information on early pregnancy BMI, 3082 were extremely preterm, 6893 were very preterm, and 67,059 were moderately preterm. Risks of extremely, very, and moderately preterm deliveries increased with BMI and the overweight and obesity-related risks were highest for extremely preterm delivery. Among normal-weight women (BMI 18.5-<25), the rate of extremely preterm delivery was 0.17%. As compared with normal-weight women, rates (%) and adjusted odds ratios (ORs [95% CIs]) of extremely preterm delivery were as follows:
- BMI 25 to less than 30 (0.21%; OR, 1.26; 95% CI, 1.15-1.37),
- BMI 30 to less than 35 (0.27%; OR, 1.58; 95% CI, 1.39-1.79),
- BMI 35 to less than 40 (0.35%; OR, 2.01; 95% CI, 1.66-2.45), and
- BMI of 40 or greater (0.52%; OR, 2.99; 95% CI, 2.28-3.92).
Risk of spontaneous extremely preterm delivery increased with BMI among obese women (BMI≥30). Risks of medically indicated preterm deliveries increased with BMI among overweight and obese women.
CONCLUSIONS AND RELEVANCE: In Sweden, maternal overweight and obesity during pregnancy were associated with increased risks of preterm delivery, especially extremely preterm delivery. These associations should be assessed in other populations.
Comment in: Obesity: effect of maternal obesity on neonatal outcomes. [Nat Rev Endocrinol. 2013]
PMID: 23757084
See also VitaminDWiki
- Obese mothers with adequate vitamin D gave birth to low D and fat infants – Jan 2013
- Half of newborn deaths are due to excessive weight of their mothers – Oct 2010
- Overview Obesity and Vitamin D
- Dark skin pregnancies and Vitamin D - many studies
could have 3 reasons to be at high risk of vitamin D deficiency: Dark Skin, Pregnant, Obese - Premature birth 2.5X more likely if mother had low vitamin D and was having twins – July 2013
- Many groups of pregnant women are at high risk of being vitamin D deficient – Jan 2013
- Twins, no tan, winter, and smoking all associated with low levels of vitamin D during pregnancy – Jan 2013
See also web
- Losing weight for baby: Mom's obesity linked to extreme preemies NBC News on this study: Sept 2013
extremely premature birth — babies born between 22 and 27 weeks
“When a baby is born earlier than it should be born, the potential for all the organs not being fully developed is increased,”
“When it comes to being obese and being pregnant, the risk factors for things going wrong multiply very quickly,” Cooper told NBC News. “Along with that comes gestational diabetes, hypertension, and preeclampsia, which can eventually lead to eclampsia, which is a condition where seizures occur.”
Note by VitaminDWiki - all of those health problems are associated with low vitamin D