view of a teenage boy and girl sitting outdoors and talking
Stockbyte/Stockbyte/Getty Images

Some women do not make enough progesterone, one of the dominant female hormones, to achieve and maintain a pregnancy. They may take progesterone supplements to increase progesterone levels before and during early pregnancy. Others take progesterone as part of hormone replacement therapy. Progesterone comes in many forms, including as micronized capsules made from plant sources. Prometrium, a type of micronized progesterone, is considered a natural progesterone, according to Women & Infants Hospital of Rhode Island.

Types of Progesterone

The term "natural" progesterone may be used to mean different things. Progesterones found in birth control pills, called progestins, are man-made chemicals with similar effects as progesterone, which the ovaries produce in early pregnancy. Natural progesterones made from plant sources include micronized oral progesterone, injectable progesterone in oil, and vaginal creams and gels. Wild yam creams are also called "natural" progesterone. Wild yam can be synthesized into progesterone in the laboratory, but your body cannot convert wild yam to progesterone on its own.


Natural progesterone supplements are often used in artificial reproductive technology to ensure that progesterone levels will remain high enough to support embryo implantation. Women who have recurrent miscarriages due to low progesterone levels may also use natural progesterone. Pregnant women should not take synthetic progestins due to the risk of birth defects. Natural progesterones are safe to use in pregnancy, the Women & Infants Hospital of Rhode Island states.

Problems With Oral Progesterone

In the past, natural progesterone was given via injection because it wasn't well absorbed by mouth. Gels and creams containing natural progesterone are well absorbed but messy and uncomfortable. Prometrium is a micronized progesterone, meaning that the drug is partially broken down for easier absorption. You can also insert Prometrium capsules vaginally.


If you're taking progesterone to increase your levels during pregnancy, it's important to take only natural progesterones such as Prometrium. Prometrium is chemically identical to the progesterone your ovaries produce. Because Prometrium contains peanut oil, you should not use this product if you have a peanut allergy. Compounding pharmacies can make micronized progesterone that does not contain peanut oil. Although the warning labels on Prometrium say not to use it in pregnancy, this product, like other natural progesterone, will not harm your baby, according to the Women & Infants Hospital of Rhode Island. Prometrium can cause drowsiness, bloating or breast tenderness.