Progesterone is a hormone — a chemical messenger the body makes. It is one of the main hormones of the female monthly cycle, though other bodies make a little too.

ProgesteroneProgesterone（黃體素） is a hormone是一種荷爾蒙——a chemical messenger the body makes身體製造出來的化學傳訊物質。It is one of the main hormones of the female monthly cycle它是女性月經週期裡主要的荷爾蒙之一，though other bodies make a little too不過其他人的身體也會製造一點點。

After an egg leaves the ovary, progesterone rises. It gets the soft inside of the womb ready, so that if a baby starts, there is a place to grow. If there is no pregnancy, the level falls, and a period begins. During pregnancy it stays high and helps keep the womb calm.

After an egg leaves the ovary卵子從卵巢排出之後，progesterone risesprogesterone 的濃度就會升高。It gets the soft inside of the womb ready它會把子宮內壁柔軟的組織準備好，so that if a baby starts, there is a place to grow這樣萬一開始懷孕，就有地方可以讓寶寶生長。If there is no pregnancy如果沒有懷孕，the level falls濃度就會下降，and a period begins月經就會開始。During pregnancy it stays high懷孕期間它會維持在高濃度，and helps keep the womb calm幫助讓子宮保持穩定。

Doctors also put progesterone, or close copies of it, in birth-control pills (they help stop the monthly egg), and sometimes use it as medicine when periods are irregular or when an early pregnancy needs support.

Doctors also put progesterone, or close copies of it, in birth-control pills醫生也會把 progesterone，或是很接近它的合成物，放進避孕藥裡（they help stop the monthly egg幫助阻止每個月排卵），and sometimes use it as medicine when periods are irregular or when an early pregnancy needs support有時候在月經不規律，或早期懷孕需要支持的時候，也會拿它當藥物使用。

Though actually, people lump ‘female hormones’ together. Oestrogen (also spelled estrogen) and progesterone work as a pair, but they are not the same job: oestrogen builds and changes many tissues; progesterone is the one especially tied to ‘ready for a baby’ and to holding a pregnancy.

Though actually不過其實，people lump 'female hormones' together人們常把「女性荷爾蒙」全部混為一談。Oestrogen (also spelled estrogen) and progesterone work as a pairOestrogen（也拼作 estrogen，雌激素）和 progesterone 是一對搭檔，but they are not the same job但工作不一樣：oestrogen builds and changes many tissuesoestrogen 負責建造、改變許多組織；progesterone is the one especially tied to 'ready for a baby' and to holding a pregnancyprogesterone 則特別跟「為懷孕做好準備」和「維持懷孕」有關。

You do not need the chemistry. You need: body chemical, monthly cycle and pregnancy, also in the pill.

You do not need the chemistry你不需要懂化學細節。You need你需要記住的是：body chemical身體裡的化學物質、monthly cycle and pregnancy跟月經週期和懷孕有關，also in the pill也用在避孕藥裡。