The Effect of Obesity on Fertility

pants being stretched

While many women are aware of the substantial impact age has on fertility, you might not realize the negative influence that excess weight can have on your reproductive health. Take a look at some of the risks associated with obesity and reproduction.

Decreased Likelihood of Conception

Obesity has a large impact on a woman’s ability to conceive. The chance of a young woman with a BMI greater than 30 kg/m2 getting pregnant is as likely as a woman aged 35 or older successfully conceiving. There is a 3% drop in monthly fecundability, or the probability of a woman getting pregnant each month, for each BMI unit above 25 kg/m2.

Additionally, obesity can have an effect on male fertility.  According to a study published by Dr. Rajeshwari Sundaram at the NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development, couples in which both partners had a BMI of at least 35 kg/m2 had greater difficulty getting pregnant than couples with BMIs of 25 kg/m2 or lower. Maintaining a healthy BMI weight is crucial to increasing your chance of conceiving.

Increased Health Risks

Obesity can be harmful in pregnant women.  According to a 2015 American College of Obstetricians and Gynecologists Obesity in Pregnancy Practice bulletin, excess weight can cause spontaneous abortion, gestational diabetes, and preeclampsia.  Obesity during pregnancy can also be dangerous for the fetus as well.  The risk of stillbirth is increased by 30% for women with a BMI of 30 kg/m2 to 34.9 kg/m2, compared to women with normal values.  The risk doubles for women with a BMI of 40 kg/m2 or higher.  Maternal obesity also increases the child’s risk of congenital anomalies, metabolic syndrome, and childhood obesity.

Will Losing Weight Help Get Me Pregnant?

While losing weight will certainly improve the health of men and women who struggle with obesity, studies have been inconclusive about the effect of weight loss on a woman’s fertility. In one study that was published in the New England Journal of Medicine, there was no benefit found from preconception weight loss on the number live births. More infants were born to overweight women who received an infertility treatment (the medication clomiphene) than women who underwent a six-month weight loss before receiving clomiphene. However, the women in this study only reported modest weight loss, which could indicate that greater weight loss is required to see positive results on reproductive health.

While the results of studies on obesity and reproductive health have been mixed, it is clear that excessive weight can increase your risk of health problems during pregnancy. Your health should be your top priority. Your body (and your future baby!) will thank you.