A baby with Down syndrome in their mother’s arms (Morse, 2022).  

Introduction 

In the United States, 1 in 33 babies are born with a birth defect each year (Birth Defects and Your Baby, 2023). Birth defects are medical conditions that occur before or at birth and can have numerous causes behind them. Although many birth defect conditions can be detected during pregnancy, some may not be found until after birth. Precautions are taken by many mothers to ensure the birthing of healthy babies and lower the risk of birthing a child with medical conditions that can alter the family’s life. In our current generation, as education has advanced for females, so has the pursuit of careers. With advancements in women’s education and careers, family life has been placed on hold for many to achieve their goals before committing to motherhood. However, I have personally witnessed some mothers I know who had kids at an older age and have faced birth defects in their newborns. These mothers have advised their fellow females pursuing a similar timeline to reconsider and plan differently to avoid medical complications.  

With any pregnancy, there will always be complications involved and many factors such as genetics and environment can play a factor in birth defects, but the age at which a mother chooses to have kids is a controllable factor in avoiding birth defects. Having kids earlier does not guarantee that a child will be born with no birth defects but has shown a lower rate of birth defects. Minimal research has been done on the correlation between maternal age and birth defects, most of which was conducted before 2010. I propose a research study to be done on the rate of birth defects in pregnant women of various ages to determine the “safe ages” to conceive. Every parent will have a different genetic history which may propose an issue but by condensing the selected population to parents without any prior genetic disorder history, the study can be performed to obtain data on the current population’s maternal age effects on the rate of birth defects. I hypothesize that as maternal age increases, birth defects will increase in the offspring. 

Background 

Known causes of birth defects include mothers who have used or were exposed to drugs or substances during their pregnancy, medical conditions of diabetes and obesity, consumption of certain medications known to have side effects if pregnant, and parents having a history of birth defects within the family (CDC, 2021). Previous research studies that have been performed on maternal age and birth defects were conducted primarily in the late 1990s and early 2000s focusing on ages 20-40. Trisomy 21, trisomy 18, trisomy 13, triple X syndrome, Klinefelter’s syndrome, and c-section delivery are some of the birth defects found in women who conceived at an older age (MARKETINGUAE, 2020). No new research has been performed in the last few years pertaining to maternal age and birth defects.  

Based on women’s reproductive years, the suggested ages of conceiving are late teens to late 20s and at the start of 30, it is said that fertility declines (The American College of Obstetricians and Gynecologists, 2020). Correlations between maternal age and fertility have been established but have lacked data on the effect of birth defects on the babies born. Research studies that have focused on maternal age and birth defects have excluded mothers carrying children with the known causes of birth defects to be able to reduce variables that prevent the researchers from seeing the direct correlation between the age of mothers and birth defects. It is believed that maternal age can be a cause of birth defects in mothers not experiencing established causes of birth defects.  

Methods 

Baird, P. A., Sadovnick, A. D., Yee, I. M. L., & Baird, P. A. (1991). Maternal age and birth defects: a population study. The Lancet, 337(8740), 527–530. https://doi.org/10.1016/0140-6736(91)91306-f 

In this study, the population focused on was the British Columbia livebirths, excluding stillbirths, in 1966 and they were observed until 1981 to provide enough time for diagnosis of birth defects. They utilized “aetiology” codes to classify and sort the birth defects of the live births into different categories based on the chromosomal disorders. Findings included no correlation between maternal age and unknown aetiology occurring if already tested for chromosomal disorders of mothers aged above 34. Focusing only on people tested for chromosomal disorders and using chromosomal disorders as the only forms of birth defects is not sufficient to conclude maternal age does not impact birth defects.  

Fett-Conte, A., & Oliveira, C. (2015). Birth defects: Risk factors and consequences. Journal of Pediatric Genetics, 02(02), 085–090. https://doi.org/10.3233/pge-13052 

This journal focused on the risk factors that contribute to birth defects and the consequences that follow. Although it was stated that increasing maternal and paternal age contributes to birth defects, advanced maternal age was related primarily to Down syndrome. The journal states that increased age’s correlation to birth defects is not clear and this suggests that more research must be conducted to obtain data to find a clear correlation. The uncertainty of the correlation between maternal age and birth defects despite assumptions is not sufficient nor is focusing on one autosomal disease, emphasizing the need for further research.   

Gill, S. K., Broussard, C., Devine, O., Green, R. F., Rasmussen, S. A., & Reefhuis, J. (2012). Association between maternal age and birth defects of unknown etiology ― United States, 1997-2007. Birth Defects Research Part A: Clinical and Molecular Teratology, 94(12), 1010–1018. https://doi.org/10.1002/bdra.23049 

A population-based case-control study was used and consisted of data from birth defect surveillance systems in multiple states within the United States. This study had an interesting finding that women under 20 years old had fewer birth defects related to chromosomal diseases but were at an increased risk for gastroschisis. However, the data included women exposed to known factors causing birth defects such as smoking cigarettes. The use of data with mothers exposed to known causes of birth defects hinders the ability to decipher a specific correlation between maternal age and birth defects.  

Harris, B. S., Bishop, K. C., Kemeny, H. R., Walker, J. S., Rhee, E., & Kuller, J. A. (2017). Risk Factors for Birth Defects. Obstetrical & Gynecological Survey, 72(2), 123–135. https://doi.org/10.1097/OGX.0000000000000405 

This article focused on common maternal risk factors for birth defects which included alcohol use, folic acid deficiency, obesity, uncontrolled maternal diabetes mellitus, uncontrolled maternal phenylketonuria, advanced maternal age, illicit drug use, smoking, advanced paternal age, radiation exposure, and much more. Chromosomal abnormalities were stated to be a result of increasing maternal age, but it was also found that nonchromosomal malformations increased after age 25. The focus on nonchromosomal malformations suggests birth defects are not limited to chromosomal diseases with increased maternal age. This provides a scope to further investigate maternal age effects on birth defects from a perspective beyond chromosomal conditions.  

Outcomes 

By conducting further research, more data can be obtained on women conceiving at an older age with present education and career dynamics. The anticipated outcomes include seeing a positive correlation between the increase in maternal age and birth defects. Birth defects beyond chromosomal conditions can be determined and established to serve as a precaution for women who plan on delaying pregnancy. Access to potential risks of pregnancies with increased maternal age can also help parents plan accordingly or seek professional help for their specific circumstances. Furthermore, it can help many families avoid facing the consequences of birth defects by taking effective measures to prevent chances of birth defects. Conducting more recent research can provide a clear correlation between maternal age and birth defects to inform future mothers whilst also giving recent data to support the conclusions drawn so it is more relevant to the present society today.  

References 

Baird, P. A., Sadovnick, A. D., Yee, I. M. L., & Baird, P. A. (1991). Maternal age and birth defects: a population study. The Lancet, 337(8740), 527–530. https://doi.org/10.1016/0140-6736(91)91306-f 

Birth defects and your baby. (2023). Www.marchofdimes.org. https://www.marchofdimes.org/find-support/topics/planning-baby/birth-defects-and-your-baby#:~:text=About%201%20in%2033%20babies 

CDC. (2021, November 5). What are Birth Defects? | CDC. Centers for Disease Control and Prevention. https://www.cdc.gov/ncbddd/birthdefects/facts.html#:~:text=Smoking%2C%20drinking%20alcohol%2C%20or%20taking 

Fett-Conte, A., & Oliveira, C. (2015). Birth defects: Risk factors and consequences. Journal of Pediatric Genetics, 02(02), 085–090. https://doi.org/10.3233/pge-13052 

Gill, S. K., Broussard, C., Devine, O., Green, R. F., Rasmussen, S. A., & Reefhuis, J. (2012). Association between maternal age and birth defects of unknown etiology ― United States, 1997-2007. Birth Defects Research Part A: Clinical and Molecular Teratology, 94(12), 1010–1018. https://doi.org/10.1002/bdra.23049 

Harris, B. S., Bishop, K. C., Kemeny, H. R., Walker, J. S., Rhee, E., & Kuller, J. A. (2017). Risk Factors for Birth Defects. Obstetrical & Gynecological Survey, 72(2), 123–135. https://doi.org/10.1097/OGX.0000000000000405 

MARKETINGUAE. (2020, September 1). What does my age have to do with my genetics? – Middle East. Www.igenomix.net. https://www.igenomix.net/fertility-challenges/what-does-my-age-have-to-do-with-my-genetics/#:~:text=Therefore%2C%20pregnancy%20in%20advanced%20age 

Morse, J. (2022, January 25). 6 things to expect with Down syndrome babies | Pediatrics | Your Pregnancy Matters | UT Southwestern Medical Center. Utswmed.org. https://utswmed.org/medblog/down-syndrome-babies/ 

The American College of Obstetricians and Gynecologists. (2020, October). Having a Baby After Age 35: How Aging Affects Fertility and Pregnancy. Www.acog.org. https://www.acog.org/womens-health/faqs/having-a-baby-after-age-35-how-aging-affects-fertility-and-pregnancy#:~:text=A%20woman