Going into a hot tub or sauna it will cause miscarriage is that correct?

No, going into a hot tub or sauna does not automatically cause a miscarriage. The temperature of a hot tub or sauna does not generally exceed body temperature, so it is unlikely to significantly harm the development of the fetus. It is important to keep in mind that every pregnant woman and their condition is unique, so consult with your healthcare provider for personalized advice during pregnancy and before taking part in any activity that affects body temperature.