Hymen

Patient's question:

1. What does the hymen look like? Is it a transparent membrane (like plastic), or a thin layer of flesh? Can it be seen with the naked eye?
2. Where is the hymen located in the vagina? I noticed that there is a semi-circular opening in my vaginal area. Is this the vaginal opening, or the opening of the hymen?
3. Does the vaginal opening appear as a visible hole on the surface? I saw some diagrams of the external genitalia that directly drew a hole, but is it really that obvious in reality? Meanwhile, they drew the hymen to the left of the vaginal opening, yet it seems like there is nothing there. What exactly does the hymen look like? Could you please describe it in detail for me? Thank you.

Doctor's answer:

Hello: The vaginal opening of a virgin also has a ring-shaped mucosal fold called the hymen, which is a thin, membrane-like tissue containing connective tissue, blood vessels, and nerve endings. It can serve to partially close the vagina. The inner edge of the hymen is sharp and intact, and the hymen of an unmarried woman is usually light red. The hymen is typically not completely sealed, with a small opening in the middle to allow menstrual blood to flow out after puberty.
The shape, size, and thickness of the opening can vary from person to person. In unmarried individuals, the hymen opening is usually crescent-shaped or elliptical, but it can also be sieve-shaped, radiating, fish-mouth-shaped, or other shapes. Its size also varies, with some so small that a finger cannot pass through, while others are large enough to accommodate two fingers. The hymen is generally about 2 millimeters thick and often breaks during the first sexual intercourse, though there are exceptions. Some hymens are too narrow or thin and may break during exercise, vibration, or the insertion of a menstrual.
From a sexual perspective, people are more concerned about the vagina because it is directly related to sexual activity. People jokingly call it a "hole" or a "barrel," but it is actually not a cave—it is a closed space, somewhat like a balloon. The vaginal walls are normally tightly pressed together but can expand fully when needed. The vagina is a highly elastic muscular organ that can contract and relax. When contracted, even a small finger cannot fit inside, but when relaxed, the penis can be inserted or moved freely, even allowing a fetus to pass through.
The tightness of a woman's vagina varies greatly. Unmarried women typically have a tight vagina with elastic muscles, but after giving birth, the vaginal walls become looser, making the vagina more relaxed. Many people lack awareness of the vagina's potential for contraction and relaxation. Men may worry about causing harm to their partner during intercourse, and women may fear that sex will hurt them. In reality, such concerns are entirely unnecessary. The vagina's potential for stretching and adjustment can sometimes be quite remarkable.
Some people worry that a too-narrow vagina may restrict penile insertion. However, truly small vaginas and truly small penises are rare. The issue often lies in the woman's response during insertion. If the woman is highly aroused, even a large penis will not be a problem. Conversely, if the woman is not aroused, even a small penis may cause difficulties. Women who have been abstinent for a long time or those postmenopausal may have slower sexual responses when resuming intercourse. Therefore, do not insert without ensuring the woman is highly aroused, as this will only cause pain rather than pleasure. When childbirth causes excessive vaginal relaxation, it not only significantly reduces the woman's external and proprioceptive sensitivity during intercourse but also affects her response to her partner's external stimuli, though to a lesser extent. In such cases, Kegel exercises can help restore the muscle's tension, elasticity, and regulatory ability.
The anterior wall of the adult woman's vagina is shorter, about 7–9 centimeters long, while the posterior wall is longer, about 9–12 centimeters. Normally, the anterior and posterior walls are tightly pressed together, giving the cross-section an "H" shape. The upper part curves downward and backward, approaching the sacral fossa, while the lower part curves forward, giving the sagittal view of the vagina an "S" shape. The upper part of the vagina is wider and surrounds the cervix. The ring-shaped cavity between the cervix and the vaginal wall is called the vaginal fornix, which is divided into anterior, posterior, and left and right parts based on its location. The posterior fornix is particularly deep and wide, serving as a seminal reservoir. In the lithotomy position, the posterior fornix is the lowest part of the vagina, which is anatomically favorable for sperm to swim from the vagina to the cervix, as the external os of the normally positioned cervix faces the posterior fornix. The posterior fornix is the most easily expandable part of the vagina, providing necessary space for an erect penis while preventing excessive cervical displacement and potential sexual difficulties.