1. The Effects of Maternal Age on Childbirth Danielle Stevens, Advisor Jennifer Hancock Introduction There have been many studies that have analyzed the effects of maternal age on pregnancy and childbirth. A study by Huang (2008) reviewed information on the rate of stillbirths in women over 30. They compiled 913 citations all involving studies on stillbirths in women of advanced age. Overall, the consensus was that advanced maternal age is very strongly associated with an increased risk of stillbirth. Research performed by Gordon Smith et al. (2007) studied the effects of maternal age on the outcome of labor. According to their research, the risk of intrapartum cesarean delivery increased in a linear fashion as maternal age increased (Smith, 2007, 1128). A study performed by Delpisheh et al. (2008) acquired medical records from a hospital and did a comprehensive study on many aspects of pregnancy and child birth at advanced maternal age. Their study included elements such as low birth weight, diabetes, preeclampsia, and whether or not the pregnancy was carried to full term. Their analysis also included other aspects of the mother’s health and included those differences in their results. When their research as complete, they concluded that in women that wait to conceive at an advanced age, there is a higher risk of complication and a greater need to carefully monitor the mother’s prenatal health (Delpisheh, 2008, 969). The purpose of this study was to determine if there is a statistically significant difference in the amount of complications in women who give birth over the age of 34 when compared to younger mothers. The key factors that were evaluated were hypertension, gestational diabetes, preterm birth, and method of delivery. The hypothesis is that women over the age of 34 will experience a significant increase in complication. Subjects Medical charts we reviewed at River Rose Obstetrics and Gynecology in Athens, OH. A total of 194 charts were reviewed from 2006-2009. The subjects were divided into three age groups: 15-24 years of age, 25-34 years of age and 35-45 years of age. Data Collection The smoking and drug/alcohol habits during pregnancy were recorded. Body mass index (BMI) was calculated using the height and weight of the subjects before pregnancy. The parity of the subjects was also recorded. A subject was considered hypertensive if a diastolic blood pressure of greater than 110mmHg was recorded on a least 1 occasion or if a diastolic blood pressure of greater than 90mmHg was recorded on 2 or more consecutive visits. The charts were flagged if a subject experienced gestational diabetes. Preterm birth was defined as birth at less than 37 weeks. Four methods of delivery (vaginal, induced vaginal, primary cesarean, and repeat cesarean) were recorded. Statistical Analysis An ANOVA was used to determine if smoking practices, alcohol/drug exposure, parity and maternal BMI can be excluded as a contributing factors for complications. Chi-square analysis was used to determine if the rate of complications differed significantly between groups. Methods Table 1 shows the chi-square analysis of preterm birth among the age groups. The Chi-square was equal to 0.275 and was not significant. Table 2 shows the chi-square analysis for hypertension among the subjects. The chi-square is equal to 0.050 and was not significant. Table 3 shows the chi-square analysis for gestational diabetes. The chi-square is equal to 7.75 and is significant. Table 4 shows the chi-square analysis for the method of delivery. The chi-square is equal to 46.8 and is significant. Results The ANOVA for BMI was not significant (p = 0.111). The ANOVA for smoking habits during pregnancy was not significant (p = 0.095), and the ANOVA for alcohol/drug use was not significant ( p = 0.382). The ANOVA for parity was a significant (p = 6.26x10 -6 ). Conclusions The hypothesis that was tested in this study was to evaluate the effect of maternal age on childbirth. It was hypothesized that the older age group would experience complications at a significantly higher rate than the younger groups. BMI, smoking practices, alcohol/drug use, and parity were evaluated to rule out the possibility that the complications were arising from these sources. BMI, smoking, and drug use were the same across all three groups, however, parity was greater in the older age groups. Since most of the possible contributing factors were ruled out, complications were evaluated based on age alone. Preterm birth and hypertension were not significantly different across the groups, therefore the hypothesis not supported for these complications. Gestational diabetes did show significant results, with a more occurrence in the oldest age group. The method of delivery was also significantly different across the age groups. The results show that more of the younger women are giving birth vaginally, whereas the older women are having more cesarean section deliveries. Therefore, for these two factors the hypothesis was supported. The parity of the mothers was a contributing factor and may be the reason why there was not a significant difference in some of the variables. In future studies it would be beneficial to select a larger cohort and to look at other factors that may be contributing to the rate of complications among older women. Chan BCP, Lao TTH. 2008. Effect of parity and advanced maternal age on obstetric outcome. International Journal of Gynecology and Obstetrics 102: 237-241. Delpisheh A, Brabin L, Attia E, Brabin BJ. 2008. Pregnancy Late in Life: A Hospital-Based Study of Birth Outcomes. Journal of Women’s Health 17(4): 965-970. Huang L. 2008. Maternal age and Risk of stillbirth: a systemic review. Canadian Medical Association Journal 178: 165-172. Smith GCS, White IR, Pasupathy D, Missfelder-Lobos H, Pell JP, Charnock-Jones DS, Fleming M. 2007. The Effect of Delaying Childbirth on Primary Cesarean Section Rates. PloS Medicine 7(4): 1123-1131. References Acknowledgments River Rose Obstetrics and Gynecology of Athens, Ohio Professor Jennifer Hancock Dr. David Brown The Marietta College Biology Department Results