A 2008 study found that over 85% of women having a vaginal birth sustain some form of perineal trauma, and 60-70% receive stitches. A retrospective study of 8,603 vaginal deliveries in 1994 found a third degree tear had been clinically diagnosed in only 50 women (0.6%). However, when the same authors used anal endosonography in a consecutive group of 202 deliveries, there was evidence of third degree tears in 35% of first-time mothers and 44% of mothers with previous children. These numbers are confirmed by other researchers in 1999.

A study by the Agency for Healthcare Research and Quality (AHRQ) found that in 2011, first- and second-degree perineal tear was the most common complicating condition for vaginal deliveries in the U.S. among women covered by either private insurance or Medicaid.

Second-degree perineal laceration rates were higher for women covered by private insurance than for women covered by Medicaid.

Several techniques are used to reduce the risk of tearing, but with little evidence for efficacy. Antenatal digital perineal massage is often advocated, and may reduce the risk of trauma only in nulliparous women. ‘Hands on’ techniques employed by midwives, in which the foetal head is guided through the vagina at a controlled rate have been widely advocated, but their efficacy is unclear. Waterbirth and labouring in water are popular for several reasons, and it has been suggested that by softening the perineum they might reduce the rate of tearing. However, this effect has never been clearly demonstrated.

One of the main causes is suggested to be excessive and repetitive straining during defecation. Other causes include weakness of the pelvic floor muscles (secondary to age related neuropathic degeneration or traumatic injury during pregnancy and labor.

Urethral strictures most commonly result from injury, urethral instrumentation, infection, non-infectious inflammatory conditions of the urethra, and after prior hypospadias surgery. Less common causes include congenital urethral strictures and those resulting from malignancy.

Urethral strictures after blunt trauma can generally be divided into two sub-types;

- Pelvic fracture-associated urethral disruption occurs in as many as 15% of severe pelvic fractures. These injuries are typically managed with suprapubic tube placement and delayed urethroplasty 3 months later. Early endoscopic realignment may be used in select cases instead of a suprapubic tube, but these patients should be monitored closely as vast majority of them will require urethroplasty.

- Blunt trauma to the perineum compresses the bulbar urethra against the pubic symphysis, causing a "crush" injury. These patients are typically treated with suprapubic tube and delayed urethroplasty.

Other specific causes of urethral stricture include:

- Instrumentation (e.g., after transurethral resection of prostate, transurethral resection of bladder tumor, or endoscopic kidney surgery)

- Infection (typically with Gonorrhea)

- Lichen sclerosus

- Surgery to address hypospadias can result in a delayed urethral stricture, even decades after the original surgery.

Surgical treatments may be used to treat the condition, and include retro-rectal levatorplasty, post-anal repair, retro-anal levator plate myorrhaphy.

The use of bioengineered urethral tissue is promising, but still in the early stages. The Wake Forest Institute of Regenerative Medicine has pioneered the first bioengineered human urethra, and in 2006 implanted urethral tissue grown on bioabsorbable scaffolding (approximating the size and shape of the affected areas) in five young (human) males who suffered from congenital defects, physical trauma, or an unspecified disorder necessitating urethral reconstruction. As of March, 2011, all five recipients report the transplants have functioned well.

Post-void dribbling or post-micturition dribbling is the where urine remaining in the urethra after voiding the bladder slowly leaks out after urination. A common and usually benign complaint, it may be a symptom of urethral diverticulum, prostatitis and other medical problems.

Men who experience dribbling, especially after prostate cancer surgery, will choose to wear incontinence pads to stay dry. Also known as guards for men, these incontinence pads conform to the male body. Some of the most popular male guards are from Tena, Depends, and Prevail. Simple ways to prevent dribbling include: strengthening pelvic muscles with Kegel exercises, changing position while urinating, or pressing on the perineum to evacuate the remaining urine from the urethra. Sitting down while urinating is also shown to alleviate complaints: a meta-analysis on the effects of voiding position in elderly males with benign prostate hyperplasia found an improvement of urologic parameters in this position, while in healthy males no such influence was found.

Obstructed defecation has many causes, so the management in any individual case is specific to the cause of the symptom. For rectal internal intususception treatment is surgical, either STARR or rectopexy. For rectocele STARR or mesh implantation. For anismus/ pelvic floor dessynergia: biofeedback exercise.

In dogs, perineal hernia usually is found on the right side. Most cases are in older intact (not neutered) male dogs (93 percent in one study). Breeds that may be at risk include Welsh Corgis, Boxers, Australian Kelpies, Boston Terriers, Collies, Dachshunds, Old English Sheepdogs, and Pekingese. Perineal hernias are rare in female dogs and uncommon in cats.

Dogs with benign prostatic hyperplasia have been found to have increased relaxin levels and suspected subsequent weakening of the pelvic diaphragm. In cats, perineal hernias are seen most commonly following perineal urethrostomy surgery or secondary to megacolon. Medical treatment consists of treatment of the underlying disease, enemas, and stool softeners. Because only about 20 percent of cases treated medically are free of symptoms, surgery is often necessary. Recurrence is common with or without surgery.

Several surgeries have been described for perineal hernias in dogs. The current standard involves transposition of the internal obturator muscle. This technique has a lower recurrence and complication rate than traditional hernia repair. A new technique uses porcine small intestinal submucosa as a biomaterial to help repair the defect. This is can also be done in combination with internal obturator muscle transposition, especially when that muscle is weak.

One review stated that the most common causes of disruption to the defecation cycle are associated with pregnancy and childbirth, gynaecological descent or neurogenic disturbances of the brain-bowel axis. Patients with obstructed defecation appear to have impaired pelvic floor function.

Specific causes include:

- Anismus and pelvic floor dysfunction

- Rectocele

- "Rectal invagination" (likely refers to rectal intussusception)

- Internal anal sphincter hypertonia

- Anal stenosis

- Fecal impaction

- Rectal or anal cancer

- Descending perineum syndrome

If cesarean section is obtained in a timely manner, prognosis is good. Prolonged obstructed labour can lead to stillbirth, obstetric fistula, and maternal death.

In 2013 it resulted in 19,000 maternal deaths down from 29,000 deaths in 1990.

In humans, a major cause of perineal hernia is perineal surgery without adequate reconstruction. In some cases, particularly surgeries to remove the coccyx and distal sacrum, adequate reconstruction is very difficult to achieve. The posterior perineum is a preferred point of access for surgery in the pelvic cavity, particularly in the presacral space. Surgeries here include repair of rectal prolapse and anterior meningocele, radical perineal prostatectomy, removal of tumors including sacrococcygeal teratoma, and coccygectomy. Perineal hernia is a common complication of coccygectomy in adults, but not in infants and children (see coccygectomy).

The standard surgical technique for repair of perineal hernia uses a prosthetic mesh, but this technique has a high rate of failure due to insufficient anchoring. Promising new techniques to reduce the rate of failure include an orthopedic anchoring system, a gluteus maximus muscle flap, an acellular human dermis graft, and an acellular pig collagen graft.

Bloody show is the passage of a small amount of blood or blood-tinged mucus through the vagina near the end of pregnancy. It can occur just before labor or in early labor as the cervix changes shape, freeing mucus and blood that occupied the cervical glands or cervical os. Bloody show is a relatively common feature of pregnancy, and it does not signify increased risk to the mother or baby . A larger amount of bleeding, however, may signify a more dangerous, abnormal complication of pregnancy, such as placental abruption or placenta previa. Large amounts of bleeding during or after childbirth itself may come from uterine atony or laceration of the cervix, vagina, or perineum.

Three common signs of the onset of labor are:

1. A bloody show

2. Rupture of membranes ("Water breaking")

3. Onset of tightenings or contractions

However, these may occur at any time and in any order. Some women neither experience a bloody show nor have their "water break" until well into advanced labor. Therefore, neither bloody show nor rupture of membranes are required to establish labor.

Odynorgasmia, or painful ejaculation, is a physical syndrome described by pain or burning sensation of the urethra or perineum during or following ejaculation. Causes include infections associated with urethritis, prostatitis, epididymitis, as well as use of anti-depressants.

A malfunctioning bladder sphincter, leading to retrograde ejaculation, may be a result either of:

- Autonomic nervous system dysfunction. (Dysautonomia)

- Operation on the prostate. It is a common complication of transurethral resection of the prostate, a procedure in which prostate tissue is removed, slice by slice, through a resectoscope passed along the urethra.

It can also be caused by a retroperitoneal lymph node dissection for testicular cancer if nerve pathways to the bladder sphincter are damaged, with the resulting retrograde ejaculation being either temporary or permanent. Modern nerve-sparing techniques seek to reduce this risk; however, it may also occur as the result of Green Light Laser prostate surgery.

Surgery on the bladder neck accounted for about ten percent of the cases of retrograde ejaculation or anejaculation reported in a literature review.

Retrograde ejaculation is a common side effect of medications, such as tamsulosin, that are used to relax the muscles of the urinary tract, treating conditions such as benign prostatic hyperplasia. By relaxing the bladder sphincter muscle, the likelihood of retrograde ejaculation is increased.

The medications that mostly cause it are antidepressant and antipsychotic medication, as well as NRIs such as atomoxetine; patients experiencing this phenomenon tend to quit the medications.

Retrograde ejaculation can also be a complication of diabetes, especially in cases of diabetics with long term poor blood sugar control. This is due to neuropathy of the bladder sphincter. Post-pubertal males (aged 17 to 20 years) who experience repeated episodes of retrograde ejaculation are often diagnosed with urethral stricture disease shortly after the initial complaint arises. It is currently not known whether a congenital malformation of the bulbous urethra is responsible, or if pressure applied to the base of the penis or perineum immediately preceding ejaculatory inevitability may have inadvertently damaged the urethra. This damage is most often seen within 0.5 cm of the ejaculatory duct (usually distal to the duct).

Retrograde ejaculation can also result from pinching closed the urethral opening, to avoid creating a mess upon ejaculation (known as "Hughes' technique").

Even with successful surgery, patients may have long-term problems with:

- incontinence, where serious usually treated with some form of continent urinary diversion such as the Mitrofanoff

- depression and psycho-social complications

- sexual dysfunction

Retrograde ejaculation occurs when semen, which would, in most cases, be ejaculated via the urethra, is redirected to the urinary bladder. Normally, the sphincter of the bladder contracts before ejaculation forcing the semen to exit via the urethra, the path of least resistance. When the bladder sphincter does not function properly, retrograde ejaculation may occur. It can also be induced deliberately by a male as a primitive form of male birth control (known as "coitus saxonicus") or as part of certain alternative medicine practices.

It is often associated with alcoholism and eating disorders and there is some evidence that presence of a hiatal hernia is a predisposing condition. Forceful vomiting causes tearing of the mucosa at the junction. NSAID abuse is also a rare association.

The tear involves the mucosa and submucosa but not the muscular layer (contrast to Boerhaave syndrome which involves all the layers). The mean age is more than 60 and 80% are men.

Hyperemesis gravidarum, which is severe morning sickness associated with vomiting and retching in pregnancy, is also a known cause of Mallory-Weiss tear.

When an infant is born with PSH, the most difficult management decision has often been the sex assignment, since genitalia with this degree of ambiguity do not resemble either sex very well with respect to looks or function. Many infants with PPHS have been assigned and raised as female despite presence of testes and XY chromosomes.

Nearly all parents of infants with PPSH are offered surgical reconstruction, to either further masculinize or feminize the external genitalia.

Treatment with testosterone postnatally does not close the urethra or change the malformation, but in some cases may enlarge the penis slightly.

Fournier's gangrene ( an aggressive and rapidly spreading infection of the perineum ) usually presents with fever and intense pain. It is a rare condition but fatal if not identified and aggressively treated with a combination of surgical debridement and broad spectrum antibiotics.

The main treatment for isolated epispadias is a comprehensive surgical repair of the genito-urinary area usually during the first 7 years of life, including reconstruction of the urethra, closure of the penile shaft and mobilisation of the corpora. The most popular and successful technique is known as the modified Cantwell-Ransley approach. In recent decades however increasing success has been achieved with the complete penile disassembly technique despite its association with greater and more serious risk of damage.

There are several misfortunes associated with precipitate delivery for both the mother and the infant. They are classified as maternal and neonatal.

Mallory–Weiss syndrome or gastro-esophageal laceration syndrome refers to bleeding from a laceration in the mucosa at the junction of the stomach and esophagus. This is usually caused by severe vomiting because of alcoholism or bulimia, but can be caused by any conditions which causes violent vomiting and retching such as food poisoning. The syndrome presents with hematemesis. The laceration is sometimes referred to as a "Mallory-Weiss tear".

Precipitate delivery may cause lacerations of the cervix, vagina, and/or perineum. Rapid descent and delivery of an infant does not allow maternal tissues adequate time to stretch and accommodate the passage of the infant.

There may be hemorrhaging originating from lacerations and/or hematomas of the cervix, vagina, or perineum. There may also be hemorrhaging from the uterus. Uterine atony may result from muscular exhaustion after unusually strong and rapid labor.

There may be infection as a result of unsterile delivery.