Adolescent obesity had detrimental effect on parity later on in life

Women who were obese during adolescence were more likely to have lifetime nulliparity and nulligravidity, according to new findings from the Study of Women’s Health Across the Nation.

“Importantly, this was true even after we controlled for adult body weight and other factors that affect fertility,” Alex J. Polotsky, MD, assistant professor of obstetrics and gynecology and women’s health in the division of reproductive endocrinology and infertility at Albert Einstein College of Medicine, told Endocrine Today.

For the cross-sectional analysis, Polotsky and colleagues examined whether adolescent obesity was associated with difficulties in becoming pregnant later in life. The study included 3,154 women aged 42 to 52 years.

Women were grouped by self-reported BMI during high school: BMI <18.5 (underweight); 18.5 to 24.9 (normal); 25 to 29.9 (overweight); or >30 (obese).

Overall, 527 women (16.7%) had never delivered a baby; 23% of the study population reported a history of infertility.

Adolescent obesity was significantly associated with adult BMI (P=.001). Further, the prevalence of lifetime nulliparity increased progressively as high school BMI increased: 12.7% for BMI <18.5; 16.7% for 18.5 to 24.9; 19.2% for 25 to 29.9; and 30.9% for >30 (P<.01).

Adolescent obesity was also associated with lifetime nulligravidity (OR=3.93; 95% CI, 2.12–7.26). Women who were obese as adolescents were significantly more likely to remain childless when compared with normal-weight women (OR=2.84; 95% CI, 1.59-5.10), according to multivariable logistic regression analysis and after adjustment for adult BMI, nongestational amenorrhea history, marital status, ethnicity, study site and socioeconomic status.

“Our study is one of the first reports that suggest reduced birth rates of obese young women over their lifetime,” Polotsky said.

“One of the potential clinical implications that our data may have for practice is increasing public awareness of the detrimental effects of obesity on fertility and reproduction,” he said. “Perhaps young obese girls may listen more carefully to advice about weight loss and exercise if they learn about the potential harmful effects of excessive weight.” – by Jennifer Southall

Polotsky AJ. Fertil Steril. 2010;93:2004-2011.