Aspiration of accumulated fluid (ascites) from the abdominal/pleural cavity may be necessary, as well as opioids for the pain. If the OHSS develops within an IVF protocol, it can be prudent to postpone transfer of the pre-embryos since establishment of pregnancy can lengthen the recovery time or contribute to a more severe course. Over time, if carefully monitored, the condition will naturally reverse to normal – so treatment is typically supportive, although a woman may need to be treated or hospitalized for pain, paracentesis, and/or intravenous hydration.[citation needed]