Complications During Pregnancy

Obesity is defined as a body mass index greater than 30 kg/m², which essentially means that the amount of body fat is disproportionate to the individual’s height.  This excess fat or adipose tissue can affect multiple body systems by disrupting metabolic, vascular, and inflammatory pathways, which can have negative effects throughout the pregnancy, during birth, and long after the infant is born.

 There are multiple potential health issues that can arise during pregnancy as a result of maternal obesity.  In fact, obese women are 5% more likely to experience a miscarriage, which is thought to be due to hormonal and inflammatory changes present in obese women.  Gestational diabetes is also significantly more prevalent in obese women due to the insulin resistance associated with increased body fat.  High BMIs are also associated with a higher incidence of pregnancy associated hypertension and preeclampsia, which is thought to be related to chronic inflammation, insulin resistance, and high lipid (fat) levels in the blood.  Placental growth and function is also affected by maternal obesity due to similar mechanisms, which cause problems in the baby's development.

Spontaneous preterm births have also been linked to obesity. It is often medically indicated to induce labor prematurely due to the presence of complications caused by maternal obesity, such as preeclampsia or diabetes.  On the other end of the spectrum, post-term pregnancies are also linked to maternal obesity, which may be due to hormonal imbalances or simply that the estimated delivery dates are calculated incorrectly due to changes in the frequency of ovulation in obese women.

Photo from:  http://www.boldsky.com/pregnancy-parenting/
basics/2012/obesity-in-pregnancy-avoiding-180112.html

References

Ramsey, P., Schenken, R., Lockword, C., Pi-Sunyer, X., & Barss, V.  (2017). Obesity in 

            pregnancy:  Complications and maternal management, UpToDate.  Retrieved from

             https://www.uptodate.com/contents/obesity-in-pregnancy-complications-

            and-maternal-management

Squibb, L. (2014).  Pregancy, delivery, and childhood obesity.  International Journal of

            Childbirth Education, 29(2), 73-77.

Zozzaro-Smith, P., Bacak, S., Conway, C., Park, J., Glantz, J., & Thornburg, L.  (2016). Association between obesity during pregnancy and the adequacy of prenatal care.  Maternal & Child Health Journal, 20(1), 158-163. doi: 10.1007/s10995-015-1815-x