There are various things you can try:
something to do with your diaphragm muscle.
Yes you can ive acctualy done it and i can tell you its not nice well if you've had hiccupps you will know what i mean.
Possibly, but it's not a very reliable symptom. Many people get frequent hiccups occasionally and aren't pregnant. If you are later for your period, take a home test. If you don't want to wait that long, go see a doctor.
They are involuntary muscle spasms and occur naturally. There is no way to prevent them completely, but some people have them far less frequently than others. If you have chronic hiccups, you should see a medical professional for advice. The one form of hiccups that is mostly preventable is from eating too much, or too quickly. The stomach can secrete too much acid, or distend, and this can trigger the vagus nerve to cause hiccups. Some cases of hiccups can be avoided by only drinking in moderation, avoiding very hot or very cold food, and avoiding cold showers. When carbonated beverages are consumed, they usually cause belches, which are not hiccups.