There are plenty of reasons to lose weight before a pregnancy. For one, being svelte before you conceive means it'll be easier for you to regain your pre-pregnancy body once your baby arrives. For another, the thought of carrying around 30 or more pounds of extra pregnancy weight can be daunting enough without worrying about your own pooch. And, if you're severely overweight, slimming down before you conceive can help your baby avoid several health issues.

In a recent study, researchers from the University of Wisconsin - Madison analysed 281 newborn babies and their mothers iron levels. Iron is crucial for fetal development - about 50 percent of the iron needed for infant growth is obtained before birth - and obesity in adults often hinders iron transmission in the intestine (and, in pregnant women, to the placenta). The women's body mass index was calculated before delivery, and a score of 30 or above was defined as obese.

The results showed evidence that babies born to obese women had deficient iron levels, which could be dangerous. So if you're thinking about starting a family, you have more reasons to get in shape besides looking great in a bikini - you'll also want to reach a healthy weight so your children can get the best shot at life.