A good way to piss off a pregnant woman:

Is when her partner/husband/fiance/boyfriend/ turns down the water heater without telling her (Again!) so that there isn’t enough hot water for a hot bath which means a luke warm bath (only to be discovered when getting into the bath, which started off hot when she ran the bath to being with) equals one pissed off mama who is very uncomfortable with constant back pain and is limping due to a painful charlie horse in her calf for the last 2 days. Not to mention the sleep deprivation and and belly ache due to constipation. That is one sure way to do it. Which renders her unable to relax thus pissing her off even further in the midst of her discomfort.