por He Chadwick’s sign refers to the change in coloration of the cervix, vagina and genital lips in a woman’s gynecological physical examination, when there is suspicion of pregnancy.
Under normal conditions, the cervix and vagina are pink mucosa, and the labia are the color of the patient’s skin. The color change of these organs, from pink/reddish to blue or violet, occurs due to increased blood supply in that area.
Chadwick’s sign is one of the first indicators that warn the doctor that he may have a pregnant patient. That is, it is the first indication of a possible pregnancy.
Subsequently, and as time goes by, other changes occur in the female anatomy. All these alterations occur with the purpose of maintaining the fetus in a state of maturation until the moment of its expulsion through the birth canal.
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Chadwick’s sign
The change in coloration of the cervix, vagina, and vulva of a pregnant woman is known as Chadwick’s sign. It is evident to the gynecologist when performing the genital examination.
These changes were first described in 1836 by the French physician Étienne Joseph Jacquemin (1796-1872). However, the eponym 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.
Despite the fact that 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 skin color of the woman.
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 vascularization and the venous congestion cause the vaginal mucosa and the cervix to acquire a purplish color from the 6th week of pregnancy approximately.
Darkening of the skin on the outer lips and mount of Venus is a common change that occurs for the same reason.
In some cases, venous vascular congestion can lead to the formation of vulvar varices that can become very annoying during pregnancy.
Anatomy
Vagina
The vagina is part of the female internal genitalia. At the top of it is the cervix; the lower part is the opening to the outside.
The vagina consists of three layers:
– Mucous layer: it is a tunic that contains mucosal folds. It reacts to hormones by changing its thickness in each phase of the menstrual cycle.
– Muscle layer: it is formed by smooth muscle fibers and musculoskeletal.
– Adventitia layer: it is the connective tissue. Contains the neurovascular plexus.
As for 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 pudendal artery.
Vulva
The set of female external genital organs is known as the vulva. It is made up of the labia majora and minora, the clitoris and the mons pubis or mount of Venus.
The vulvar anatomy differs greatly from one person to another depending on the build, 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 pudendal, internal pudendal, and deep external pudendal).
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 inside 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 designed to keep the fetus in the uterus until the time of birth. A full pregnancy lasts between 38 and 40 weeks.
Some of the physical alterations in pregnant women are recognized with the naked eye, such as the increase in the size of the uterus or breasts.
However, in addition to these changes in the physiognomy of the woman, there are also subtle modifications that can be evidenced by the doctor during the gynecological physical examination.
These alterations can be found in early stages of pregnancy and are known as probable signs 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 late menstrual period, 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 signs of probability.
The signs of probability 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 are evident during the physical examination, the doctor should indicate a series of tests that confirm the diagnosis.
Although 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. For this reason, 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 heart activity through ultrasound with Doppler effect (ultrasound function that shows blood flow in an organ).
Physiological changes that occur in pregnant women, such as increased irrigation, modification of the collagen fibers of the uterine tissue, and increased pigmentation of the external genitalia and nipples, are some of the probable signs that lead to pregnancy. specialist to guide the definitive diagnosis of pregnancy.
References
Gossman, W; Fagan, SE; Sosa-Stanley, JN; et al. (2019). Anatomy, Abdomen and Pelvis, Uterus. Stat Pearls (FL). Taken from: ncbi.nlm.nih.gov
Chaudhry R, Chaudhry K. (2018). Anatomy, Abdomen and Pelvis, Uterine Arteries. Stat Pearls (FL). Taken from: ncbi.nlm.nih.gov
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
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
Seeman, M.V. (2014). Pseudocyesis, delusional pregnancy, and psychosis: The birth of a delusion. World journal of clinical cases. Taken from: ncbi.nlm.nih.gov