November 20, 2017

A 26-year-old, formerly obese woman steps into Dr. Marie Menke’s office with a small, happy tear forming in her right eye. They’ve been meeting for months, discussing non-invasive methods for reaching a healthy weight and increasing fertility. Now, forty pounds lighter than when she first walked into that same room, a smile spreads across the woman’s face. “I did it,” she says, “I got pregnant on my own.”

It’s success stories like these that drive Dr. Menke, a reproductive endocrinologist with Magee-Womens Research Institute and an OB/GYN with UPMC, to help women achieve healthy pregnancies. For her, much of the battle against infertility and obesity comes down to education and making sure the patient knows exactly what her options are, especially since obesity and infertility are often closely linked.

But Dr. Menke’s insight into the factors that make for a healthy and successful pregnancy doesn’t just come from years of education and experience. When she’s not in the exam room with patients, she spends a good deal of her time in the lab, trying to understand the mysterious link between infertility and obesity.

Polycystic Ovary Syndrome and Weight Loss in Mice

Marie Menke, MD, MPH

To learn more about that link, Dr. Menke has taken a deep dive into polycystic ovary syndrome (PCOS), a disease that can impact both lean and obese women—but with a greater impact on the latter. The disease, which often presents itself outwardly with excess acne and hair, causes elevated male hormones and many small cysts on the ovaries. Women with PCOS also have a decreased number of periods and trouble getting pregnant because they don’t always ovulate. While this can happen to women of all body types, obesity seems to increase the chances for ovulatory and menstrual cycle dysfunction. Because of this, Dr. Menke suspects PCOS stems from excess adipose (fat) tissue, as adipose tissue is capable of creating weak strains of hormones that can disrupt the balance within a woman’s body.

Partially because of that hunch, Dr. Menke and a team of researchers turned their attention to mice. With the hypothesis that less fat tissue would increase fertility, the team mutated an enzyme within the mice that prevented fat cells from being used for energy, essentially causing the mice to drop their excess weight. But the researchers soon discovered something fascinating. While the male mice soon died off because of the weight loss, the female mice were somehow able to reverse the effects of the mutation; they were able to regain their excess weight. The results shocked Dr. Menke and her team, who were unable to pinpoint exactly what caused the different reactions.

“The nice part about doing studies with both sexes is they may actually help you identify things in one particular sex that may help the other,” Dr. Menke says. “Each sex has different hormone structures, so that may have an effect, but it’s too soon to conclude with any certainty.”

As incredible as the results were, the findings were less exciting: the team was unable to find a marked increase in fertility among the female mice with the mutated enzyme when they dropped the weight. “Why that is, we’re not 100% sure yet. It does seem like the eggs do need some fat for energy. There must be a delicate balance, though, between too little and too much, and that requires more evaluation.”

It’s also going to take more work to understand why the female mice were able to regain the fat stores, and what this suggests, if anything, about fat growth in women.

Fat Tissue and Infertility

That’s not to say we don’t know anything. Previous studies have shown the majority of women seeking help with infertility are obese, as infertility is three times higher in obese women. Obese women also require more time to achieve pregnancy, a fact demonstrated by a study that found the probability of pregnancy decreases 5% for each unit of BMI exceeding 29 kg/m2.

Still, there’s plenty more to learn about the connection between fat tissue and infertility. Based on the studies, there’s much we don’t understand about good and bad fats within the body. But Dr. Menke is optimistic we’ll crack the code soon. Because of the research happening in labs right now, she believes we’ll understand the role of these fats within the next decade.

In the meantime, Dr. Menke and her colleagues are focused on what can be done now to help women struggling with infertility, especially in areas where obesity rates are higher. One study with Dr. John Harris, a primary investigator at Magee-Womens Research Institute, has analyzed the geographic distribution of In Vitro Maturation (IVM) centers across the country. While they’ve found that here’s still a large number of women who don’t have any facilities nearby, these centers are pivotal in helping obese women in remote areas overcome infertility, especially as long as obesity rates remain high.

A Healing Touch

Overcoming infertility is easier by first overcoming obesity. Obesity has skyrocketed over the last three decades, something Dr. Menke attributes to increased food portion sizes, lifestyle decisions, and sedentary environments. Worse, the health aspects of obesity have been downplayed, Dr. Menke claims. “As physicians, we need to always tell patients that obesity has an impact. You could compare it to smoking, where physicians recognize that it’s very hard to quit, but they continue to explain what the potential consequences are. Patients need to be able to make their own choices based on the evidence in front of them, as opposed to living under the impression that everything will be okay without making changes.”

That’s why Dr. Menke makes a point of sitting with patients so they understand their treatment options for infertility. Dr. Menke goes down the list of necessities for preparing the body for conception: reaching a healthy and stable weight (being obese or overweight often interferes with pregnancy), maintaining a healthy lifestyle (getting regular exercise, eating properly, etc.), knowing the body (especially the menstrual cycle), and setting realistic expectations (most healthy women only have a 20-25% chance of getting pregnant in a given month). It’s her hope that with education, some patients will be able to take control of their health in such a way that they’ll be able to get pregnant on their own, without invasive medical intervention.

Her research has made her much more comfortable talking to patients about obesity. “I used to feel like I was being judgmental, but when you look at the data you see that it’s a necessary thing to talk about, however uncomfortable it may be. The worst thing that could happen is having a patient that doesn’t know. If they don’t want to make any changes, that will be their decision, but even if only one out of so many decide ‘I’m going to try to lose the weight,’ that’s a success.”

Support Dr. Menke’s research into obesity and infertility by donating to Magee-Womens Research Institute today!