IPOs in the United States may be lagging overall, but in med-tech we have seen a flurry of IPO activity, sparking some long overdue optimism regarding the health of the industry. Most recently, Natera, a California-based company, began trading (NASDAQ: NTRA) this past Thursday at $22.10 after pricing 10 million shares of its common stock at $18, the high end of the expected $17 to $18 range. Natera is a genetic testing company that develops non-invasive methods for analyzing DNA. ConforMIS, a Massachusetts-based company, also received a warm welcome from investors when it began trading last Wednesday (NASDAQ: CFMS) at...