What weight should you be to get pregnant?

You hear it often, but I have to say it again: your weight is a major factor affecting your fertility and pregnancy outcomes.

When you are about to embark on a new pregnancy, your body does an audit. You could compare it to a financial assessment of starting a major construction project. It’s about evaluating the risk as well as available resources.

Your body’s resources are what you don’t use immediately, the storage of glycogen and fat among other nutrients.

When some women don’t have enough body fat, they will struggle to produce healthy levels of hormones for pregnancy. This can get so bad that you will stop ovulating and having periods.

But what happens if your weight is too high?

We may argue that the body’s resources are abundant, but with excess fat you may face other fertility challenges.

Being overweight taxes your body. You may be using your energy for fighting chronic conditions associated with higher weight like inflammation, sleep deprivation, pain, high blood pressure, dysregulated reproduction (HPO) axis. In short, the resources you need to fall pregnant, you use up for managing chronic conditions.

No two overweight women are the same. One will fall pregnant easily and the other will struggle.

One of these women has a healthier diet, controls her weight, and exercises. While the other eats fast food and sits on the couch. It’s like one of them is putting money in the bank each month and the other is drawing down. And even if at a given moment, their account balance may look similar, the risk assessment and prognosis you can do in each situation is desperate.

This is the reason, when considering a fertility diet, the first element we need to discuss is your weight.

Calculate your BMI here.

What does your BMI say about chances to conceive?

If your BMI is

  • below 18.5 you are underweight,
  • between 18.5 and 24.9 is normal, healthy
  • above 25 you are overweight, and
  • Over 30 falls into the obese category.

However, keep in mind that BMI is just an indication. The are weaknesses:

  • Body mass index, it doesn’t show your actual fat mass. Your BMI could be within the normal range, but you could store unhealthy amounts of fat. Or opposite, you can have a high BMI, but a healthy fat mass.
  • Does your body store fat abdominally?  This is also a factor. BMI does not reflect this.

Despite this, most research articles commonly use BMI to describe the relationship between weight and your chances to fall pregnant. For this reason here, we are going to use BMI as a weight indicator. This must be viewed in the context of your general health and lifestyle.