Melanie Cole (Host): While exercise and maintaining healthy weight are so important, physical activity should be done in moderation when trying to get pregnant and certainly something that you should speak to your healthcare provider about. My guest today is Dr. William Ziegler. He's a specialist in reproductive endocrinology and infertility and he's the Medical Director of the Reproductive Science Center of New Jersey. Welcome to the show, Dr. Ziegler. So, we're always told to exercise and it helps us get healthy and maintain a good, healthy pregnancy, but during fertility and conception and trying to get pregnant, is exercise--can it be both good and bad?

Dr. William Ziegler (Guest): Yes. Which exercise and infertility will vary from individual to individual. There is no really just one size fits all. We do know that exercise and infertility are linked and we know that being overweight is just as bad as being underweight. Those that undergo a very vigorous exercise regime, may be actually hurting their chances for conceiving.

Melanie: Wow. So what do we consider you know, a vigorous routine? What do you consider that?

Dr. Ziegler: Well, there's been some research out that basically has mentioned that women who exercise four hours or more per week, have a forty percent less likelihood of having a live birth versus those that don't. So, even just exercising four hours per week can actually compromise fertility. It's very hard to quantify what is a strenuous exercise as well as they type of exercise. We know like with men, those that are bike riders have a lower sperm count than those that don't and a lot of it has to do with the equipment, has to do with what they're wearing, and the temperature in which the testicles are at because they are kind of wedged between the body and the seat of the bicycle. With women, again, we try to target their heart rate. We like to have the heart rate, if they're going to be working out, to be between 110 and 120. We don't want it to be at a range which is for weight reduction. We also look at body mass index and we like to have the body mass index between 20 and 25 and that would equal around 117 to 145 pounds for someone whose five feet, four inches tall.

Melanie: Well, this is so contrary to what most people hear about the benefits of exercise. So, when you are working with women and discussing fertility treatments and such, when you're telling them about exercise and they're questioning you, "But I thought I was supposed to take walks and go for runs and keep doing aerobics," or whatever it is, what are the reasons that you tell them?

Dr. Ziegler: Well, what we kind of tell patients is very similar to when you eat and you go out running and you get stomach cramps. You don't use your stomach to run, so when you do vigorous exercise, the blood's going to go to the organs that need it, to the muscles, to the lungs, to the heart, and to the brain. As with reproduction, you don't use your uterus and you don't use your ovaries to do vigorous exercise, so we try to have them curtail that. If they want to participate in vigorous exercise, we usually recommend it just during their period time, but during a treatment cycle, we kind of recommend curtailing any cardio activity. I kind of bring up the suggestion of what's called “mall walking”. It's walking in the mall. You're just strolling. If you want to do isolated muscle groups, that's fine, but nothing that's going to be classified as cardio activity.

Melanie: So, we want to watch out for our heart rate, and does the internal body temperature, does that have something to do with it, or can it inhibit ovulation? What's happening?

Dr. Ziegler: Well, the big thing is that with just exercise, you do have an increase in adrenaline, and adrenaline can affect the pituitary hormones. It can also affect peripheral fat tissue, which basically produces a hormone called “leptin”. Leptin kind of communicates to your higher centers within your brain to tell it that I'm healthy enough to get pregnant. If you start having these drastic weight losses, then the Leptin levels fall and the pituitary gland reads that as “Well, I'm not healthy enough to get pregnant. I am under a lot of stress”, and it starts to shut down someone's ovulation. So, that's kind of where the whole thing with exercise comes into play.

Melanie: So, if a woman is already in very good shape and exercises a lot, and then they're having a little trouble getting pregnant and you tell them to curtail it and then do you sort of keep a watch on whether that was one of the causes, or is this something that now she has to sort of curtail until she's pregnant?

Dr. Ziegler: Well, a lot of times, when women are exercising, like especially gymnasts, that they notice their cycles start becoming irregular and then they actually stop. In that situation, it's usually because of low body fat. We know that women that are involved with dance and even the Rockettes, we had some of them as patients, that when they start training for the Christmas show, their periods stop, not because of the weight loss, but because of the strenuous exercise and the stress in which they're under. So, then and what we do recommend to our patients is again to help them get pregnant, to curtail those activities. We watch their cycles and see if they start becoming regular. If they don't become regular within a certain period of time, and we usually say within three or four months, then it's time for us to intervene and possibly even use medication to help them ovulate.

Melanie: So, exercise basically is just individual. Is that what you're saying? Kind of give us your best advice about what you tell patients and what you tell women about including exercise in their daily regime, whether they should cut back, or how individual is it, really?

Dr. Ziegler: Well, we actually take a look at their body fat, you take a look at their body mass index, and we take a look at the type of activities in which they are participating in. If they are long-distance runners and they like running marathons, we kind of recommend again, curtailing that and, like I mentioned before, we just say casual walking is fine, but nothing that's power walking and if they want to free weights, that's fine, also, but nothing that's going to cause them to do cardio, or something in which they want to lose weight.

Melanie: So, you basically just don't want to worry about the weight loss while you're trying to conceive.

Dr. Ziegler: Right.

Melanie: That's great advice, Dr. Ziegler. It really is great advice. So, just tell us why women should look to the Reproductive Science Center of New Jersey for their care

Dr. Ziegler: Well, we kind of look at couples as part of the team and it's kind of a team approach. We want to do what's comfortable for them, and we want to address their needs, both medically and psychologically. A lot of times you have to look outside the box, take a look at their social habits, and kind of even address those, which a lot of times, patients do not find that being a big issue.

Melanie: Wow. It's great information. Thank you so much for being with us today. You're listening to Fertility Talk with the Reproductive Science Center of New Jersey. And for more information, you can go to www.fertilitynj.com. That's www.fertilitynj.com. This is Melanie Cole. Thanks so much for listening.