One of the most interesting things I learned had to do with the effects of exercise and stress on obesity. Quick endocrine lesson for you, when the body is under stress it secretes a hormone called cortisol. This signals the body to make a few changes that basically puts your body in a hypothyroid state. You have probably heard about the body reducing metabolic rate when a person is fasting — this is the process that causes that.
Just as an aside, feeling out of control, being a perfectionist, having a high need for social approval and having overly high expectations of yourself all cause this stress response.
So why is this interesting? It turns out that while a metabolic stress (such as not eating) and a social stress (such as being a perfectionist or having a high need for acceptance) can each cause about a 10% increase in hormonal response; when they are combined they cause a 70% increase in hormonal response. When this was studied in monkeys the stress was so extreme it was found that their regular menstrual cycles stopped. Being underweight has a stronger effect on fertility than being overweight, but once a woman is pregnant the underweight woman actually has fewer pregnancy problems.
Stress has effects during pregnancy as well, for example it increases the risk of preterm labor, increases the risk of congenital malformations and the risk of poor fetal neuro-development.
The moral of this story was short and sweet, you need to understand the problems the woman is dealing with to help her reach her optimal health. If obesity is an issue, look for indications that the woman is under excess stress. As you form a plan to help her maintain the healthiest weight possible, remember when a woman is already stressed and exercising is adding to that stress it has the potential to sabotage her weight loss efforts rather than help them. For some overweight women, the secret to weight loss success not exercise, but to lessen to stress in their lives. This does not mean exercise is without value, but not every woman is at a point in her journey to health for exercise to have the weight loss benefits we are normally inclined to expect.