* Q3 net profit 374 mln euros, vs 244 mln forecast
* Q3 sales down 4 percent to 1.55 bln euros (Adds detail)
AMSTERDAM Nov 8 (Reuters) - Dutch insurer Aegon beat expectations for quarterly net profit, helped by lower impairment charges, higher investment returns and a stronger dollar.
Aegon said on Thursday third-quarter net profit rose to 374 million euros ($477 million), compared with a forecast for 244 million in a Reuters poll.
Underlying earnings rose 31 percent to 472 million euros, beating a forecast for 435 million, while sales fell 4 percent to 1.55 billion.
Aegon reported 405 million euros in life insurance sales in the period, mostly in the United States with weaker markets in the Netherlands, Britain and Spain.
Chief executive Alex Wynaendts said while there were signs of gradually improving market conditions, there remained considerable uncertainty. "Consequently ... it is prudent and necessary to maintain a sufficient financial buffer while at the same time adhering to our strict risk and pricing discipline." ($1 = 0.7840 euro) (Reporting by Anthony Deutsch; Editing by Dan Lalor)