CHADWICK'S SIGN - WHAT IS IT, ANATOMY, PREGNANCY, DIAGNOSIS - ANATOMY AND PHYSIOLOGY - 2024

The Chadwick 's sign refers to the discoloration of the cervix, vagina and labia in gynecological physical examination of a woman, when suspected pregnancy.

Under normal conditions, the cervix and vagina are pinkish mucous, and the vaginal lips are the color of the patient's skin. The change in color of these organs, from pink / reddish to blue or purple occurs due to the increase in blood supply in that area.

By Inferis - https://www.flickr.com/photos/inferis/98747420/, CC BY-SA 2.0, The Chadwick sign is one of the first indicators that warns the doctor that a pregnant patient may have. In other words, it is the first sign of a possible pregnancy.

Later, and as time passes, other changes occur in the female anatomy. All these alterations occur with the purpose of maintaining the fetus in a maturing state until the moment of its expulsion through the birth canal.

Chadwick sign

Chadwick's sign is the discoloration of the cervix, vagina and vulva of a pregnant woman. It is evident to the gynecologist when performing the genital examination.

These changes were described for the first time in 1836 by the French physician Étienne Joseph Jacquemin (1796-1872). However, the eponymous of the sign comes from the name of Dr. James Read Chadwick, who in 1886 wrote and published a series of cases describing the changes evidenced by Jacquemin.

Although the physiological alterations discussed in Chadwick's publication credited Jacquemin as the first to describe them, Chadwick became popular for the name of this sign.

The internal genitalia, cervix and vagina, are pink colored organs similar to the mucosa of the mouth. The color of the vulva matches the woman's skin color.

Both the vagina and the vulva are organs that receive an extensive blood supply from various arterial groups forming a true arterio-venous network.

During pregnancy, blood flow to and from the external genitalia increases, causing venous congestion. Both the increased vascularity and venous congestion cause the vaginal mucosa and cervix to acquire a purplish color from approximately the 6th week of pregnancy.

Darkening of the skin on the outer lips and mons pubis is a common change that occurs for the same reason.

In some cases, venous vascular congestion can lead to the formation of vulvar varicose veins that can become very bothersome during pregnancy.

Anatomy

Vagina

The vagina is part of a woman's internal genitalia. At the top of it is the cervix; the lower part is the opening to the outside.

CC BY-SA 3.0, The vagina consists of three layers:

- Mucous layer: it is a tunic that contains mucous folds. It reacts to hormones by changing its thickness in each phase of the menstrual cycle.

- Muscle layer: it is made up of smooth and musculoskeletal muscle fibers.

- Adventitial layer: it is the connective tissue. It contains the neuro-vascular plexus.

Regarding the blood supply of the vaginal mucosa, it is made up of an important arterial network that involves direct branches of the uterine arteries, the hypogastric artery and the internal pudenda.

Vulva

The vulva is known as the set of external genital organs of women. It is made up of the labia majora and minora, the clitoris and the mons pubis or mons pubis.

By No machine-readable author provided. Daniduc ~ commonswiki assumed (based on copyright claims). - No machine-readable source provided. Own work assumed (based on copyright claims)., Public Domain, The vulvar anatomy differs a lot from one person to another depending on the texture, size, skin color, thickness of the labia minora, among other characteristics; therefore, it is not possible to describe specific anatomical features that are common to all women.

The vulva is abundantly supplied by the three pudendal arteries (superficial external pudenda, internal pudenda, and deep external pudenda).

Pregnancy

The term pregnancy refers to the physiological changes that occur in the woman so that she can maintain and cope with the pregnancy.

For its part, the term gestation is the development of the fetus within the uterus. Gestation begins when the embryo implants in the uterus and ends with birth.

Pregnancy consists of three periods of three months each or trimesters. When the woman begins the third trimester, the fetus is already viable to live outside the uterus.

- Physiology

Pregnancy begins when the embryo, which is the egg fertilized by the sperm, implants itself in the deep layer of the uterus. There it receives adequate blood nutrition to continue its development.

Once this occurs, a series of physiological changes begin in the woman that are intended to keep the fetus in the womb until the moment of birth. A full pregnancy lasts between 38 and 40 weeks.

Some of the physical alterations in pregnant women are recognized by the naked eye, such as an increase in the size of the uterus or breasts.

However, in addition to these changes in the woman's physiognomy, there are also subtle modifications that can be evidenced by the doctor during the gynecological physical examination.

These changes can be found in the early stages of pregnancy and are known as signs of probability of pregnancy.

- Diagnosis

Signs of certainty and signs of probability

There are signs and symptoms that make a woman suspect a pregnancy. Some of them are well known, such as delayed menstruation date, morning sickness, and breast pain and enlargement, among others.

During the gynecological physical examination of a woman who suspects pregnancy, the specialist doctor pays special attention to the so-called probability signs.

Probability signs are the changes that can be found in a pregnant woman and that guide the diagnosis but do not ensure that the patient is pregnant.

The signs of probability give a high degree of suspicion of pregnancy and if one or more is evident during the physical examination, the doctor should order a series of tests that confirm the diagnosis.

Despite the fact that these signs are present in a large percentage of pregnant women, there are conditions such as pseudocyesis or psychological pregnancy, in which the woman can experience these changes without actually being pregnant. This is why the diagnosis must be confirmed.

Those signs that ensure the diagnosis of pregnancy are known as certainty signs. Among them are:

- Pelvic ultrasound that shows the presence of the fetus in the uterus.

- Fetal cardiac activity through ultrasound with Doppler effect (ultrasound function that shows blood flow in an organ).

From Guimi - http://guimi.net Own work, CC BY-SA 2.5, Physiological changes that occur in pregnant women such as increased blood flow, modification of collagen fibers in uterine tissue, and increased pigmentation of the external genitalia and nipples, are some of the likely signs that lead to specialist to guide the definitive diagnosis of pregnancy.

References

1. Gossman, W; Fagan, SE; Sosa-Stanley, JN; et al. (2019). Anatomy, Abdomen and Pelvis, Uterus. StatPearls (FL). Taken from: ncbi.nlm.nih.gov
2. Chaudhry R, ​​Chaudhry K. (2018). Anatomy, Abdomen and Pelvis, Uterine Arteries. StatPearls (FL). Taken from: ncbi.nlm.nih.gov
3. Motosko, CC, Bieber, AK, Pomeranz, MK, Stein, JA, & Martires, KJ (2017). Physiologic changes of pregnancy: A review of the literature. International journal of women's dermatology. Taken from: ncbi.nlm.nih.gov
4. Bastian, LA; Piscitelli JT. (1997) Is this patient pregnant: can you reliably rule in or rule out early pregnancy by clinical examination? Taken from: ncbi.nlm.nih.gov
5. Seeman, MV (2014). Pseudocyesis, delusional pregnancy, and psychosis: The birth of a delusion. World journal of clinical cases. Taken from: ncbi.nlm.nih.gov