Marry in Pakistan and wait for your husband to sponsor you through consular processing. Chances of coming in to see a US citizen fiancee when you are 6 months pregnant - not too great. Also maybe you guys should consider him visiting you. Your fiancee should work with an experienced attorney to have the process go smooth.
This is not legal advice and a client attorney relationship is not created. For a free consultation call (718)234-5588.
You may request the visitor's visa, but I think you will have a hard time proving the required non-immigrant intent as your fiance lives in the United States and the consular officer may think you are coming to stay. I had a client in a similar situation and she requested the visitor visa and it was granted. But I think that's more the exception than the rule.
I am sorry about your father. But, I must agree with Ms. Vaisman ... you should forget about trying to get a tourist visa ... especially since you are pregnant and it will soon be dangerous to fly.
Get married and file for the greencard.
Don't worry, the child will be a US Citizen and you can get his/her passport at the US Consul the same time as you get your papers.
PROFESSOR OF IMMIGRATION LAW for over 10 years -- This blog posting is offered for informational purposes only. It does not constitute an attorney-client relationship. Also, keep in mind that this is an INTERNET BLOG. You should not rely on anything you read here to make decisions which impact on your life. Meet with an attorney, via Skype, or in person, to obtain competent personal and professional guidance.
The fees to apply for a visitor visa to the US is less than $100. The worst the consular officer can do is deny your application for a visitor visa. A denial should have no adverse effect on the immigrant visa petition your husband will be filing for you once you two are married.
There is always that chance that you will be interviewed by a consular officer who will look beyond the strict language of law and approve your visitor visa application.