There’s a lot that happens once ovulation occurs! Your hormones go up and then down–a bit of a roller coaster ride. This is part of the reason why many people with periods experience a wide range of symptoms during this time!

Let’s dive into it a bit more. If you want to refresh your memory on what happens in the follicular phase, check out this post.

Progesterone Production

After ovulation, the follicle shell, now called the corpus luteum, produces progesterone.

Progesterone peaks about six to eight days post-ovulation, influenced by luteinizing hormone (LH). This is why progesterone is tested during this part of the menstrual cycle!

Progesterone causes some noticeable changes, like a slight rise in basal body temperature (BBT) and thicker, tackier, and more acidic cervical mucus. This mucus acts as a natural contraceptive, making it harder for sperm to survive and move compared to more fertile mucus.

Uterine Changes & Luteal phase length

During the luteal phase, the endometrial lining goes through a process called decidualization, making it more receptive to a potential pregnancy.

While both estrogen and progesterone are needed, progesterone plays a major role. It stabilizes the lining, recruits immune cells, and stimulates blood vessel growth.

If pregnancy occurs, decidualization continues, and the corpus luteum keeps producing progesterone and estrogen, as well as inhibin A to maintain the thick endometrial lining, prevent uterine contractions, and block new follicles from developing.

If there’s no pregnancy, then the sac called the corpus luteum breaks down after about ten to twelve days. This means a period will start roughly two weeks after ovulation. 

If you ovulate, you should have a period around 2 weeks later. This is a great retrospective tool for gauging ovulation–once you get a period, look back and see if you ovulated 12-14 days ago!

Obviously, there are time when this measurement can be inaccurate, like in cases of luteal phase defect, where the corpus luteum doesn’t produce enough progesterone, or the uterus doesn’t respond well to it. This can cause fertility issues, premenstrual spotting, recurrent pregnancy loss, and short menstrual cycles.

As the corpus luteum deteriorates in the late luteal phase, it becomes the corpus albicans. The levels of progesterone and estrogen drop, triggering a series of events: follicle recruitment for the next cycle, destabilization of the uterine lining, immunological changes, inflammation, and menstrual bleeding to shed the built-up lining.