It's not known how the woman was related to the family at this stage.
Gaining popularity over the last few years, gender reveal parties are hosted by expectant parents to reveal the sex of their impending arrival.
Often the announcement can be something as simple as cutting a cake to find pink or blue inside, or releasing a balloon to determine the gender.
However, in recent years, many parents have amped up the celebrations by finding bigger and better ways to surprise their guests.
In Australia last year a car which was bellowing out blue smoke was abandoned by the driver after the car burst into flames.
The same year a gunshot at a party in the US sparked a wildfire that burned almost 47,000 hectares of land, resulting in $US 8 million in damage.