What There Is To Know

The luteal phase

The luteal phase corresponds to the second half of the cycle in women. What happens during this period? What is the role of hormones at this time? Why is the luteal phase so important if a pregnancy is scheduled?

The different phases of the cycle

The female cycle that begins on the first day of menstruation physiologically comprises two phases: the follicular phase and then the luteal phase, of similar duration and separated by ovulation

During the first phase, called the follicular phase, a follicle (contained in one of the ovaries) will grow, ripen, and eventually rupture, letting an egg escape. It is ovulation that occurs in the middle of the cycle. During this first phase of the cycle, while developing, the follicle makes hormones: estrogen.

After ovulation, the second phase of the cycle is set up: the luteal phase ...

What happens during the luteal phase?

The luteal phase has 2 phases:

  • The glandular transformation phase from the 15th to the 21st day: under the combined action of estrogen and progesterone, which has just appeared after ovulation, the glands present in the thickness of the uterine lining become more important.
  • The glandular secretion phase from the 22nd to the 28th day: the glands and small arteries developed in the mucous membranes.

This is exactly how it works:

After ovulation, a follicle breaks, changes and forms a kind of small gland called yellow body.

In addition to estrogen, the corpus luteum then secretes progesterone, the hormone of motherhood, whose essential function is to prepare the endometrium for implantation of the embryo.

In case of fertilization (encounter of a spermatozoon with an egg), the corpus luteum continues its secretions of hormones allowing the pregnancy to be well put in place.

Without fertilization, the life of the corpus luteum is limited to twelve days, after which it involutes and disappears. Hormonal levels fall, the rules occur. Depending on ovulation, the duration of the luteal phase may be shorter.

What effects do ovarian hormones have on the endometrium?

During the first part of the cyle (follicular phase) under the influence of estrogen, the uterine lining gradually thickens. And the glands of the cervix produce cervical mucus, a clear, viscous liquid that is essential for the sperm to rise to the egg.

In the second part of the cycle, that is to say during the luteal phase, under the influence of progesterone, the lining of the uterus is transformed and ready to receive the egg (in case of fertilization between a spermatozoon and the egg). The cervical mucus thickens and becomes impermeable to spermatozoa (which will no longer move towards the uterus).

In the absence of fertilization, the progressive desquamation of the lining of the uterus over a few days will constitute the rules (or menstruation).

To understand better, here is a schematic presentation of ovulation and rules:

Author: Dr. Nicolas Evrard
Expert consultant: Dr. Alain Tamborini, gynecologist.

Popular Posts

Category What There Is To Know, Next Article

Rules: daily life and hygiene during menstruation - What There Is To Know
What There Is To Know

Rules: daily life and hygiene during menstruation

Hygiene during menstruation Perfect hygiene is imperative during menstruation because it not only keeps you clean and avoids unpleasant odors, but also protects against infections. Here are some tips to follow during the period of the rules: Wash daily with an intimate soap or mild soap, without going too deep into the vagina to avoid altered vaginal flora
Read More
Abortion (IVG): the different forms of abortion - What There Is To Know
What There Is To Know

Abortion (IVG): the different forms of abortion

Depending on the technique used, and especially the progress of pregnancy, the abortions can be done by going to a city doctor, or a center of orthogeny (public or private institution). Here describes the two forms of voluntary termination of pregnancy. Drug-induced abortion can now be practiced in the office by a liberal doctor who has made an agreement with a public hospital or clinic
Read More
The vagina - What There Is To Know
What There Is To Know

The vagina

The vagina is one of the parts of the female genitalia. It opens at the level of the vulva and small lips. The term vagina is often used to designate the entire external genitalia of the woman, but this name is incorrect, the vagina being internal. The correct term for the external genitalia is the "vulva"
Read More
Emergency contraception: Another morning pill - What There Is To Know
What There Is To Know

Emergency contraception: Another morning pill

Since 2009, another pill of the next day is available: called EllaOne®, in pharmacy. The active substance used for its composition is ulipristal acetate, and contrary to the classic morning after pill that becomes inactive after 3 days, EllaOne® remains effective for 5 days following unprotected or poorly protected sexual intercourse (that's all even taking it soon after the report that it will be the most effective).
Read More