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After giving birth to her daughter in 2009, Allison Karavos happily lost her 30 pounds of baby weight (plus another 10 she'd been trying to lose pre-pregnancy) by eating right, walking with the stroller, and breastfeeding. She was thrilled to say sayonara to the weight -- but about five months postpartum, she regained 15 pounds. She attributed it to slips in her eating and new-mommy exhaustion: "I thought it was because I was tired and craving carbs. I figured it was normal after having a baby."
However, when she started having vision problems, noticed that her voice sounded gravelly, and experienced joint pain and numbness in her hands, she went to her doctor, who gave her a blood test. It turned out that the weight gain and other symptoms were due to severe hypothyroidism. Karavos's thyroid gland, which regulates metabolism, was under-active. "There's an increased chance of a woman developing a hypothyroid condition during or right after pregnancy because of changes in the immune system," explains Pamela Peeke, M.D., author of Body for Life for Women. Untreated, hypothyroidism can lead to obesity, infertility, and heart disease.
After Karavos was put on a thyroid supplement to jump-start her thyroid and metabolism, her energy returned. "I noticed a difference almost right away. I wasn't in as much pain. My vision cleared up. I was sleeping better and within a week I could walk around the mall more easily," she says. Plus, being more active helped her lose weight. Today, she is expecting her second child and working with her doctor to maintain healthy thyroid levels during her pregnancy.
Like Karavos, many women attribute their mysterious weight gain or bloating to being a busy mom. But if you're doing all the right things (exercising regularly, eating right, and getting plenty of sleep) and still can't fit into your clothes, see your doctor to determine if a medical condition could be sabotaging your ability to stay slim. Read on for a rundown of some of the most common culprits.