I'm not a doctor but I'm pretty sure a fetus is fine at the same temperature as it's mother. Pregnancy actually makes cooling itself more difficult for females and hormones can make it symptomatically worse. But so long as the mother's core temperature is operating within acceptable ranges the baby should be fine. I would think the conception process would be the issue more so than fetal development. If the fetus survives long enough to become a fetus most of the difficult work is done.

She looks 110% done with his shenanigans.