Q&A: Can being overweight affect my chances of getting pregnant?

To understand the answer to this question, you need to have an idea about how the body works. There are two sources of estrogen in the body: the ovary (directly) and the adrenal gland (indirectly). The ovary estrogen phases—up and down—in what are part of the variations of a normal menstrual cycle. Additionally adrenal glands make something called androstenedione, which is related to cholesterol, and actually even testosterone and progesterone. So it's common that hormones often are converted back and forth. In the case of the adrenal androstenedione, fat cells convert it into estrone—an estrogen.

So, if you're significantly overweight, while your ovaries are trying to behave and cycle normally, the steady input of estrone from this other pathway will interfere. A steady supply of estrogen will blunt the peaks and valleys of the ovary's function, which ultimately interferes with ovulation. Also, all of this estrogen can even lead to precancerous changes in the womb (uterus)—which are usually reversible.

Besides causing increased risk of heart disease, hypertension, and diabetes, obesity can also cause biochemistry to gang up on your chances for decent ovulation.

So how can you tell whether your weight is affecting your fertility?

• If you're having regular periods, then you're probably having regular ovulations.
• If your periods are sporadic, then probably so are your ovulations. Fewer ovulations mean fewer chances to become pregnant.