It’s also responsible for breast development and preparing the body for breastfeeding.
Progesterone keeps a balance withestrogen, the other primary sex hormone in those assigned female at birth.
Progesterone also helps to producetestosterone, the primary sex hormone in males.
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Recap
Progesterone is produced primarily by the ovary after ovulation and the placenta during pregnancy.
It’s also made in lesser amounts by the adrenal glands and the testes.
Function
Progesterone plays a few different roles, starting with causing breasts to grow at puberty.
Its main jobs are preparing the body for pregnancy and supporting a pregnancy if it occurs.
Progesterone is the dominant hormone inthe luteal phase, which is the second half of a menstrual cycle.
The luteal phase begins after ovulation and continues until the first day of your period.
Breast Development
Beginning at puberty, progesterone stimulates the growth of breast tissue.
During each luteal phase, the breast tissue is stimulated.
Mastalgia(breast pain) due to the swelling is a common symptom ofpremenstrual syndrome (PMS).
If you become pregnant, progesterone prepares your breasts for milk production andlactation.
Menstrual Cycle
After ovulation, the corpus luteum ramps up its progesterone production.
This results in a period and a new menstrual cycle begins.
At around 10 weeks, the placenta takes over progesterone production for the remainder of the pregnancy.
Progesterone is at its highest point in the third trimester.
Progesterone is critical in supporting a pregnancy because it thickens the uterine lining.
A thick uterine lining helps a fertilized egg grow into an embryo, and then to a fetus.
Progesterone levels fluctuate throughout the menstrual cycle and increase after ovulation to prepare the uterus for pregnancy.
If pregnancy occurs, progesterone is produced by the placenta to help maintain the pregnancy.
Progesterone is also responsible for breast growth at puberty and to prepare for breastfeeding.
Recent studies suggest that progesterone supplements may help prevent miscarriages.
One way progesterone does this is via its metabolite, a compound known as allopregnanolone.
Allopregnanolone works on a particular receptor in your brain called the GABA receptor.
It also contributes to fatigue that’s common during the early part of pregnancy.
For some people, the luteal phase rise in progesterone can cause varying degrees of anxiety and agitation.
It is thought that this reaction is due to a disruption in the processing of allopregnanolone.
Micronized progesterone, which is decreased in particle size for longer effect, can be taken in some instances.
Supplemental progesterone may also be used during IVF orintrauterine insemination (IUI)to help promote pregnancy.
For Contraception
Oral medications containing progestins are commonly used as a contraceptive to prevent pregnancy.
An increase in progesterone and its properties prevents ovulation.
Different synthetic progestins act on the progesterone hormone receptors in your body.
Progestins are used in allhormone-containing contraceptivesincluding:
Most of these synthetic progestins are derived from testosterone.
Taking an estrogen replacement alone will effectively treat these symptoms and protect your bones.
Progesterone can be supplemented in certain situations.
Forms include pills,shots, vaginal gels, and suppositories.
It also plays a role in breast development and preparing for breastfeeding.
In males, progesterone produced by the adrenal glands and testes plays a role in making testosterone.
Different types and formulations ofsupplemental progesteronehave many different usesincluding helping promote pregnancy and for contraception.
If you have any concerns about your hormone levels, discuss them with your healthcare provider.
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