Pumping while PG?

A couple weeks ago we found out we are expecting baby #2 (I'm about 7w). We are super excited, as it took us 2 1/2 years to conceive DD1. I exclusively breastfeed, which requires pumping 2x/day at work. Since becoming pg, my supply has tanked. I called Lactation to ask for some guidance in keeping my supply going, at least thru the end of the month, when DD1 will be 1 yo. I was told that I may need to stop pumping because the suction of a pump versus a baby can be too strong and can cause early labor, primarily in high risk pregnancies. She then told me to talk to my OB. The nurse at my OB said she thought I could keep pumping but didn't seem too certain and said she'd need to talk to my Dr.

All in all, I feel confused and felt that in talking to both nurses, that not only did they not really know the answers but they seemed to be saying I need to accept that my supply is tanking and I may need to supplement with formula this last month. Between pumping at work, nursing at home and using some freezer stash, I am pretty sure we can make it. My question is this--does anyone have experience with continuing to pump while pg? In terrified of doing something to jeopardize our unborn baby's health but want to give my daughter the best nutrition possible while I can. Thank you in advance for your advice!