It's difficult to pinpoint an exact weight that is "too small" for pregnancy, but a Body Mass Index (BMI) below 18.5 is generally considered underweight and can negatively impact fertility.
The Impact of Low Weight on Fertility
According to research, being underweight can make it more difficult to conceive. Here's why:
- Irregular or Absent Periods: Many women with a BMI below 18.5 experience irregular or absent menstrual cycles, indicating irregular or absent ovulation. Without regular ovulation, conceiving naturally is very difficult.
- Hormonal Imbalance: Low body weight can disrupt the hormonal balance necessary for ovulation and maintaining a healthy pregnancy.
- Increased Risk of Preterm Birth: Even if conception occurs, being underweight increases the risk of preterm birth.
BMI as a General Indicator
BMI is a calculation that uses your height and weight to estimate body fat. While not a perfect measure, it provides a general indication of whether you're at a healthy weight.
| BMI Category | BMI Range |
|---|---|
| Underweight | Below 18.5 |
| Normal weight | 18.5 - 24.9 |
| Overweight | 25 - 29.9 |
| Obese | 30 or greater |
Taking Action
If you have a BMI below 18.5 and are trying to conceive:
- Consult with a Healthcare Provider: Talk to your doctor or a registered dietitian to assess your overall health and develop a safe weight gain plan.
- Focus on Healthy Weight Gain: Aim for a gradual and healthy weight gain through a balanced diet rich in nutrients. "Gaining just a few pounds may make a difference in your likelihood of conceiving."
- Address Underlying Issues: Rule out any underlying medical conditions that may be contributing to your low weight.
