The periodic cycle
Periodic cycle clip
Fertilization process clip
What is the ovulatory phase (Ovulation)?
In French
Introduction
Important stage in a woman's active life: the periodic cycle.
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​From puberty, the menstrual cycle takes shape to become the metronome of a woman's active life with its worries, its joys when a desired pregnancy is revealed.
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The ovulatory phase is crucial for finding the ovulation peak.
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The ovulatory phase is decisive in guaranteeing pregnancy. It is of short duration, a maximum of 72 hours. This is why you should not miss it if you want to be pregnant.
With PRIMEVIEW digital (ovulation test*) this “critical” period is more than 99% detectable.
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The ovulatory phase is generally between the ninth and nineteenth day. The ovulation hormone (LH) increases during this time to reach a peak. It is when it reaches this peak which lasts barely 3 days that fertilization is ideal.
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* By carrying out a test every day for 7 to 15 days you will know which are the ideal ovulation days to “get” pregnant.
Failure to appear on a specific date usually does not cause much concern, as various factors can disrupt the menstrual cycle. However, if this issue occurs frequently or unpredictably despite using contraception, it is advisable to consult a healthcare professional.
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Missing periods can also result from recent unprotected sex, especially if your menstrual cycle has always been regular. In such cases, the possibility of pregnancy cannot be excluded. A home pregnancy test offers a quick and easy solution to confirm or rule out this possibility.
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Thanks to modern pregnancy tests, a reliable result of up to 99% can be obtained as early as 4-5 days before the expected period delay. Thus, a test conducted on the first day of the absence of menstruation can provide almost certain confirmation.
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Take the time to review the information about our latest-generation pregnancy test and our blog, which will undoubtedly provide answers to any questions you may have.
I didn't have my period
The follicular phase (before the release of the follicle - egg)
​At the beginning of the follicular phase, estrogen and progesterone levels are low. Consequently, the superficial layers of the uterine lining (endometrium), which have thickened, disintegrate and are shed, leading to the onset of menstrual bleeding. During this stage, the level of follicle-stimulating hormone (FSH) increases slightly, initiating the development of numerous follicles (fluid-filled sacs), each containing one egg. As the follicular-stimulating hormone levels decrease later in this phase, typically a single follicle continues to develop. This particular follicle produces estrogen, causing a steady rise in estrogen levels.
The luteal phase (after the ovulatory phase)
During the luteal phase, which follows the ovulatory phase, levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) decrease. After releasing the egg, the ruptured follicle closes and transforms into the corpus luteum, which begins to secrete progesterone. Throughout most of this phase, estrogen levels also remain elevated. The combined effects of progesterone and estrogen facilitate the gradual thickening of the uterine lining, preparing it for the possibility of fertilization.
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If fertilization does not occur, the corpus luteum breaks down, leading to a decrease in progesterone production. This decrease, in turn, causes estrogen levels to drop, which triggers the breakdown and shedding of the uterine lining, marking the onset of menstrual bleeding and the start of a new menstrual cycle.
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Conversely, if fertilization occurs, the corpus luteum is maintained and continues to function during the early stages of pregnancy. It plays an essential role in supporting the pregnancy by continuing to produce progesterone, which is vital for maintaining the uterine lining and supporting the early growth of the embryo.
oocyte
fertility window
OVULATION
FSH
Estrogen
LH
Progesterone
th day
follicular phase
days
luteal phase
days
primary follicle
follicular cells
secondary ovocyte
follicular fluid
mature follicle (follicle of Graf)
ruptured follicle
early corpus luteum
corpus luteum fully formed
atretic follicle
corpus albicans
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Periodic cycle
The Ovulatory Phase - LH Detection - Fertilization
The ovulatory phase begins with an increase in the levels of luteinizing hormone (LH) and follicle-stimulating hormone. Luteinizing hormone stimulates the release of the egg (ovulation), which usually occurs 16 to 32 hours after the start of the hormonal surge. Estrogen levels decrease during this peak, and the increase in progesterone levels begins.
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With an ovulation test that detects luteinizing hormone (LH) and is generally done from the 10th day of the cycle, you will have the opportunity to know the most fertile period, which is between the 13th and 14th day of the cycle with a margin of error of ± 1 day.
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This will increase your chances of becoming pregnant through scheduled and well-managed fertilization.
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So, a question may arise:
Why take an ovulation test if I know the fertility window to be between the 13th and 14th day?
Ovulation tests can be particularly useful even if you know that the ovulatory peak usually occurs between the 13th and 14th day of the cycle, for several reasons:
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Individual Variability: Although the typical ovulation period is between the 13th and 14th day for a 28-day cycle, there is great variability from one woman to another and even from one cycle to another in the same woman. Ovulation tests can help identify the exact moment of ovulation, especially in women with irregular cycles.
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Fertility Window: Sperm can survive in the female reproductive system for about 5 days, and the egg remains viable for about 24 hours after ovulation. Using ovulation tests can help identify the optimal fertility window to maximize the chances of conception.
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Confirmation of Ovulation: Ovulation tests detect the rise of LH (luteinizing hormone) in the urine, which occurs about 24 to 36 hours before ovulation. This can confirm that ovulation is about to occur, which can be reassuring, especially for couples trying to conceive.
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Planning: For couples trying to conceive, knowing the exact time of ovulation can help strategically plan sexual intercourse to increase the chances of pregnancy.
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Reproductive Health Monitoring: For some women, regular use of ovulation tests can help identify patterns or irregularities in their cycle, which can be useful for diagnosing potential fertility issues.
In summary, although the ovulation period can be predicted with some generality, ovulation tests offer a more precise and personalized method to identify the optimal time for conception.
The pregnancy
Preparing for eviction
After 9 months
An essential stage in the early phases of pregnancy, implantation describes the moment when the embryo implants itself in the uterine lining.
What is at stake during these crucial days?
Definition of implantation
Implantation refers to the moment when the embryo fully embeds itself into the lining of the uterus. This pivotal stage in pregnancy begins approximately on the 7th day after fertilization, which corresponds to about the 21st or 22nd day after the start of the last menstrual period, and extends until around the 10th day of pregnancy.
The implantation
We often conflate fertilization and gestation. However, the initial days, or even hours, of pregnancy are critical, marked by events essential for the successful implantation of the embryo into the uterine lining. Here are the main steps:
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Segmentation: After dividing into two equal cells (blastomeres) within just 30 hours, the egg continues to divide into 4, 8, and then 16 cells, 60 hours post-fertilization. At this stage, it is referred to as a morula, resembling a blackberry.
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Migration: Starting from the 72nd hour, the embryo begins to move from the outer part of the fallopian tube towards the uterine cavity. During this 3-day journey, the composing cells differentiate. On one side is the embryonic bud, and on the other, the trophoblast, which will develop into the placenta. This stage is called the blastocyst.
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Arrival in the Uterus: This occurs 4 to 5 days after fertilization. The embryonic pole then attaches to the uterine mucosa, initiating the implantation process.
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Implantation Process: Between 7 and 10 days post-fertilization, the embryo embeds itself in the uterine lining through several stages. By the 7th day, its outer cells (the trophoblast) produce enzymes that facilitate its integration into the outer layer of the mucosa, known as the epithelium. This 'docking' period lasts until the 9th day post-fertilization, when the blastocyst fully embeds into the mucosa. By the 10th day, a temporary plug of uterine fibers seals the breach created by the embryo's passage during implantation.
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Cellular Development: During the implantation days, cellular development progresses vigorously:
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In the second week of pregnancy, the embryonic disc, derived from the embryonic bud and the blastocyst, forms. Initially consisting of two layers, it evolves into three layers by the 5th week of gestational age. This step is crucial as all the embryo's cells will originate from this disc.
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On the 8th day post-fertilization, the amniotic cavity forms as the embryonic bud and the trophoblast separate. Enclosed by a membrane called the amnion, the well-known amniotic sac, in which the baby develops over the next nine months, begins to grow.
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Fertilization - gestation
Implantation, HCG and symptoms
It is this phase that particularly interests us and which allows us to determine a pregnancy from this moment.
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If we cannot really speak of symptoms of implantation, the hormonal impregnation essential to the success of gestation can be at the origin of the famous signs of pregnancy that we often seek to identify as early as possible (swelling breasts, fatigue, irritability, etc.).
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Indeed, during these first days of gestation and implantation, 2 major hormones interact:
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progesterone, produced in large quantities by the corpus luteum in the ovaries (which also releases estrogen), prevents normal uterine contractions during periods from taking place and participates in the thickening and vascularization of the uterine mucosa. Its objective: to maintain the pregnancy.
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the hormone HCG (chorionic gonadotropin) is secreted by the trophoblast to ensure the maintenance of the activity of the corpus luteum for 3 months, the time that the placenta can ensure exchanges between mother and child. The secretion of this hormone begins with implantation, 9 days after fertilization. Thus, before becoming pregnant, the HCG level is stable around 8 IU / l. After implantation, it doubles every 2 to 3 days until around 8 weeks before stabilizing around 5000 IU/l for the remainder of the pregnancy. It is by measuring the HCG level that the pregnancy is confirmed (by urine test and/or serology), even if the exact dating of the gestation is only possible with ultrasound but with PRIMEVIEW digital A SUFFICIENT DATE PRECISE allows you to determine the status of your pregnancy up to 3 weeks after implantation.
FOR MORE INFORMATION REGARDING PRIMEVIEW digital click below