Obsessive–compulsive disorder (OCD) is an anxiety syndrome characterized by the presence of recurrent or persistent thoughts, impulses or images (obsessions) that are experienced as intrusive or distressing by the person, and that he or she attempts to ignore or suppress by performing repetitive behaviours or mental acts (compulsions). 

Epidemiological studies report a lifetime disorder's prevalence of 1–4% in the general population, equal for men and women, although it is more commonly diagnosed among boys than girls. Most of the time, symptoms of OCD occur before age 25. 

Symptoms (Pic. 1) usually begin gradually, tend to vary in severity throughout the individual’s life, and generally worsen when intense stress is experienced by the person. Common symptoms include uncontrollable, reoccurring thoughts (obsessions) and behaviors (compulsions). OCD, considered a lifelong disorder, can be so severe and time-consuming to the point of significantly interfering with the person’s normal routine, occupational (or academic) functioning, or usual social activities or relationships. 

The cause is unknown. Both environmental and genetic factors are believed to play a role. Risk factors include a history of child abuse or other stress-inducing event.

Possible causes of OCD:

  • Genetics - There appear to be some genetic components with identical twins more often affected than non-identical twins. Further, individuals with OCD are more likely to have first-degree family members exhibiting the same disorders than do matched controls. 
  • Autoimmune - A controversial hypothesis is that some cases of rapid onset of OCD in children and adolescents may be caused by a syndrome connected to Group A streptococcal infections, known as pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS).

There are several subtypes of obsessive-compulsive disorder described:

  1. Contamination obsessions with washing/cleaning compulsions - Patients usually focus on feelings of discomfort associated with contamination and wash or clean excessively to reduce these feelings of stress.
  2. Harm obsessions with checking compulsions - Patients have intense thoughts related to possible harm to themselves or others and use checking rituals to relieve their stress.
  3. Obsessions without visible compulsions - This subtype often relates to unwanted obsessions surrounding sexual, religious, or aggressive themes.
  4. Symmetry obsessions with ordering, arranging, and counting compulsions - Patients feel a strong need to arrange and rearrange objects until they are "just right”.
  5. Hoarding - The main symptom and characteristic of hoarding is the obvious inability to discard of objects.

Most adults recognise that their obsessions and compulsions do not make sense, but that is not always the case. In addition, children may not realise that something is wrong, and too often even healthcare professionals do not identify the need for appropriate interventions, contributing to make OCD a very difficult-to-treat disorder. 

Formal diagnosis may be performed by a psychologist, psychiatrist, clinical social worker, or other licensed mental health professional. To be diagnosed with OCD, a person must have obsessions, compulsions, or both, according to the Diagnostic and Statistical Manual of Mental Disorders (DSM). Several features characterize clinically significant obsessions and compulsions. Such obsessions, the DSM says, are recurrent and persistent thoughts, impulses or images that are experienced as intrusive and that cause marked anxiety or distress. These thoughts, impulses or images are of a degree or type that lies outside the normal range of worries about conventional problems. A person may attempt to ignore or suppress such obsessions, or to neutralize them with some other thought or action, and will tend to recognize the obsessions.

There are different ways to treat OCD. These include psychotherapies, drugs (antidepressants) or a combination of both. Cognitive–behavioural therapy (CBT) combined with antidepressant medication currently represents the best treatment option for OCD. This blended intervention does not provide a ‘cure’ for OCD, but controls the symptoms and enables people with OCD to restore normal functioning in their lives.


OCD is characterized by persistent and intrusive thoughts, images, and urges (obsessions; eg, contamination, pathological doubt, somatic concerns, symmetry) and repetitive behaviors or mental acts generally performed under rigid sets of rules in response to obsessions (compulsions; eg, checking, washing, counting). Typically, patients acknowledge the illogical or exaggerated nature of these thoughts and behaviors but struggle to overcome obsessions and resist engaging in compulsions. In the context of OCD, obsessions or compulsions are time-consuming (eg, take >1 hour per day) or cause clinically significant distress or impairment in social, occupational, or other important areas of functioning. 

Sufferers of OCD also generally display many non-OCD symptoms, such as signs of depression, excessive worry, extreme tension as well as severe occupational, social and family dysfunction. Aside from the compulsive behaviours, there are no physical symptoms of OCD; however, OCD sufferers can develop physical problems. For example, in the presence of germ obsession, they may wash their hands (Pic. 2) so much as to make their skin red, raw and painful.

Most people with OCD present with both obsessions and compulsions, but some persons may experience just one or the other. OCD symptoms manifestation also vary greatly from individual to individual, and access to flexible, innovative, affordable and evidence-based psychological treatments for OCD is required.

Associated diseases

Major depressive disorder

Major depressive disorder (MDD) is a debilitating disease that is characterized by depressed mood, diminished interests, impaired cognitive function and vegetative symptoms, such as disturbed sleep or appetite. Compared with the general population, patients with MDD report substantial functional impairment. The level of functional impairment associated with depression has been shown to equal or exceed that associated with other severe chronic general medical conditions, such as diabetes and congestive heart failure.


Complications of OCD include anxiety with panic symptom, depression (Pic. 3), and suicidal thoughts.


Anxiety is an emotion characterized by an unpleasant state of inner turmoil, often accompanied by nervous behavior, such as pacing back and forth, somatic complaints, and rumination. It is the subjectively unpleasant feelings of dread over anticipated events, such as the feeling of imminent death. Anxiety is not the same as fear, which is a response to a real or perceived immediate threat, whereas anxiety is the expectation of future threat.


Depression may directly cause infertility as the physiology causes elevated prolactin levels, the upset of the Hypothalamic–pituitary–adrenal axis (control system that refers to the hypothalamus, pituitary gland, and gonadal glands), thyroid dysfunction and problems with ovulation in women.

The mood disorders in man may also lead to decreased fertility through the induction of some sexual disorders (e.g. erectile dysfunction) and through the negative impact on semen quality caused by hormonal imbalance.

Risk factors


Twin studies show a high heritable component to OCD, with concordance rates of 80%–87% in monozygotic twins and 47%–50% in dizygotic twins. There is a fourfold increased risk of OCD among relatives of probands.

Changes in brain structure

Previous neuroimaging studies have demonstrated that changes of white (WM) and grey matter (GM) in several brain regions seem to be involved in the pathogenesis of OCD.


People who have experienced abuse (physical or sexual) in childhood or other trauma are at an increased risk for developing OCD.


It is not possible to prevent OCD from starting, but the best way to prevent a relapse of OCD symptoms is by staying with the therapy and taking any medicines exactly as they have been prescribed.

OCD-associated stress and anxiety (either chronic or acute) can really throw off fertility, as in any stress and anxiety disorder. Although the psychological consequences of infertility are evident, it is not so clear how psychological disorders can affect fertility.

Female fertility

In women, unhealthy stress reaction of the body may break gonadotropin-releasing hormone pulsation (GnRH; utmost importance in controlling the menstruation cycle) and lead to anovulation when the ovaries do not release the egg during a menstrual cycle. The egg cannot meet the sperm, and hence not fertilized.

Male fertility

The mood disorders in man may also lead to decreased fertility through the induction of some sexual disorders (e.g. erectile dysfunction or ejaculatory disorders) and through the negative impact on semen quality caused by hormonal imbalance. Sexual dysfunction may cause difficulty conceiving. And vice-versa, attempts to conceive may cause sexual dysfunctions.

Quality of life is reduced across all domains in OCD. One mechanism by which depressive disorders may influence fertility is by the symptoms of decreased energy, libido, self-esteem, increased guilt and psychomotor retardation.

While psychological or pharmacological treatment can lead to a reduction of OCD symptoms and an increase in quality of life, symptoms may persist at moderate levels even following adequate treatment courses, and completely symptom-free periods are uncommon. 

In pediatric OCD, around 40% still have the disorder in adulthood, and around 40% qualify for remission.

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