Yeah, It usually happens during pregnancy.
Pregnancy Hormones have been found to play a significant part in causing hemroids in females, as does the extra weight carried during pregnancy contribute to the development of hemroids.
For the most part, most pregnant women decide to put up with the hemroids until after the baby is born.

Some relief tips for hemorrhoids in pregnancy:

1. Many women find relief from alternating hot and cold treatments.

2.  In addition to this treatment regimen, do be sure to only use plain, soft, white toilet paper or premoistened wipes.

3. Never sit on a toilet for too long trying to make something happen, that will only make the hemroids worse.


You can find many more informations as above by going to this link:
http://www.hemorrhoidshemroids.com/pregnancy-prolapse-hemroids-hemorrhoids.html.
It's a good one. I think it can help you.