Low Progesterone in Women

Hey guys, question on behalf of my fiance here. Lately my fiance’s period has disappeared (spotted last month, completely gone this month). It’s happened before and last time it happened she was told by doctors that her progesterone was low. I’m not sure if it is related but she was tested in China. Unfortunately she doesn’t still have the paperwork which tells exactly what the progesterone levels were but here are her symptoms in addition to her period loss (she’s 26 years old, 100 pounds, 5’3" or so):

moodswings,
extreme tiredness despite lots of sleep,
unexplained weight gain/water retention/puffiness
cold feet
dry skin, possible loss of appetite

She says it was recommended she undergo progesterone injections. Any input from you guys? Thanks as always for the free advice.

There are numerous potential causes of secondary amenorrhea (defined as missing at least 3 periods in someone who previously had normal menses) or oligomenorrhea (<9 cycles per year or >35 day long cycles), and “low progesterone” alone is not adequate to explain what’s going on.

Without seeing her full laboratory evaluation it’s hard to be of much help here. Is she still in China? Or can she be seen by a gynecologist in the U.S.?