Why your weight matters when you want to have a baby

October 24, 2019 | by Karen Druzak, MD
Categories: Healthy Driven Moms

If you’re thinking about starting a family, you may also be thinking about how to prepare for a healthy pregnancy.

Maybe you set up a preconception visit with your doctor, started taking folic acid or a prenatal vitamin and quit some unhealthy habits. Are you missing anything?

Another important factor in a healthy pregnancy is a healthy weight. Being overweight or underweight can affect your ability to get pregnant, cause problems during pregnancy and affect the health of your baby.

Why exactly does your weight matter when you want to have a baby?

If you’re overweight (body mass index or BMI is 25 - 29.9) or obese (BMI is 30 or greater), it affects your:

  • Fertility – As your BMI climbs, it can become more difficult to get pregnant. One reason is that being overweight or obese can cause you to stop ovulating. Studies suggest that overweight or obese women can increase their chances of getting pregnant by losing weight. According to the American College of Obstetricians and Gynecologists, losing even a small amount of weight (about 10-20 pounds) can improve your overall health and pave the way for a healthier pregnancy.
  • Pregnancy – Obesity during pregnancy puts you at risk of several serious health problems, including gestational diabetes, preeclampsia (high blood pressure) and sleep apnea, all which come with complications. The higher a woman’s BMI, the greater the risk of miscarriage and stillbirth. Overweight and obese women also have longer labors and are more likely to have a c-section, which can pose a greater risk of infection, bleeding and other complications than for women of normal weight.
  • Baby’s health – Babies born to mothers who are overweight or obese are at higher risk for health problems, such as birth defects (neural tube defects, heart defects), obesity, type 2 diabetes and high cholesterol.

Likewise, being underweight (BMI is 18.5 or less) affects your:

  • Fertility – Being underweight can cause your body to stop making estrogen, which can cause irregular periods. If your body fat drops so low, you could stop ovulating and your periods could stop completely.
  • Pregnancy – Your body needs to be able to support a developing baby. If you're underweight at the start of your pregnancy, you have a greater risk of having your baby early. Preterm babies (born before 37 weeks of pregnancy) are more prone to infection, jaundice, breathing problems and long-term health issues.
  • Baby’s health – Babies born to mothers who are underweight are at higher risk for health problems, such as low birth weight (smaller than 5.5 pounds). Low birth weight babies are more likely to have breathing or vision problems among others, and health problems later in life like heart disease, diabetes and developmental disabilities.

Making the decision to start trying for a baby is a huge milestone. The more physically and mentally prepared you are, the healthier your journey will be. Reaching a healthy weight can improve your chances of a healthy pregnancy and baby. Since a healthy weight is different for everyone, talk to your doctor about what it means for you.

If you struggle with excess weight and obesity, you are not alone. For some women, weight loss surgery can offer renewed hope. Keep in mind, most doctors recommend waiting for 12-24 months to get pregnant after weight loss surgery.

Endeavor Health® Weight Management at Edward-Elmhurst Health offers surgical and non-surgical options to help you achieve permanent weight loss and the healthy, active life you were meant to live. To schedule an appointment call, 331-221-6100.

The Family Birthing Centers at Edward-Elmhurst Health provide expert care from the minute you decide to have a baby until well after your child is born. Learn more about our pregnancy and baby services.

Find an OB-GYN.

Related blogs:

7 steps to take before you start trying for a baby

Tips to stay healthy during pregnancy

Fit mamas benefit during pregnancy and after

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Tips to stay healthy during pregnancy


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