Orofacial clefts occur very early in pregnancy and so smoking cessation right after recognition of pregnancy is unlikely to reduce the exposure during the critical time period.Maternal alcohol use has also been linked to cleft lip and palate due to the effects on the cranial neural crest cells. The degree of the effect, however, is unknown and requires further research. Some forms of maternal hypertension treatment have been linked to cleft lip and palate. Other environmental factors that have been studied include seasonal causes (such as pesticide exposure); maternal diet and vitamin intake; retinoids (members of the vitamin A family); anticonvulsant drugs; nitrate compounds; organic solvents; parental exposure to lead; alcohol; cigarette use; and a number of other psychoactive drugs (e.g. cocaine, crack cocaine, heroin). Current research continues to investigate the extent to which folic acid can reduce the incidence of clefting. Folic acid alone or in combination with vitamins and minerals prevents neural tube defects but does not have a clear effect on cleft lip palate incidence. The mechanism behind beneficial folate supplementation is due to folate playing a pivotal role in DNA synthesis and methylation and contributes to both development and gene expression. Diagnosis
Traditionally, the diagnosis is made at the time of birth by physical examination. Recent advances in prenatal diagnosis have allowed obstetricians to diagnose facial clefts in utero with ultrasonography.Clefts can also affect other parts of the face, such as the eyes, ears, nose, cheeks, and forehead. In 1976, Paul Tessier described fifteen lines of cleft.
Women may be more aware of PVCs at the time of the menstrual period.Premature ventricular contractions may be associated with underlying heart disease, and certain characteristics are therefore elicited routinely: the presence of signs of heart disease or a known history of heart disease (e.g. previous myocardial infarction), as well as heart disease or sudden cardiac death in close relatives. PVCs and palpitation associated with syncope (transient loss of consciousness) or provoked by exertion are also concerning. Physical examination is focused on identifying evidence of underlying heart disease. Causes
Premature ventricular contractions occur in healthy persons of any age, but are more prevalent in the elderly and in men. In a very significant proportion of people they occur spontaneously with no known cause.Some possible underlying causes of PVCs include:

Non-cardiac causes
Adrenaline excess
Anemia
Catecholamine excess
Certain medicines such as tricyclic antidepressants, digoxin, sympathomimetics, aminophylline
Chemical (electrolyte) abnormalities in the blood (for example hypokalemia (low blood potassium), which can occur in those taking diuretics ("water pills") and hypomagnesaemia (magnesium deficiency)). Contact with the carina (trachea/bronchi) when performing medical suctioning stimulates vagus nerve
Drugs/substances such as:Amphetamines
Alcohol
Caffeine
Cocaine
Nicotine
Theobromine
Hypercapnia (CO2 poisoning)
Hypertension (high blood pressure)
Hyperthyroidism
High blood calcium
Hypoxia and/or hypercapnia
Lack of sleep/exhaustion
Sarcoidosis
Smoking
Stress
Anxiety

Cardiac causes
Any structural heart disease which alters electrical conduction pathways due to tissue alterations
Cardiomyopathy, hypertrophic or dilated
Myocardial infarction
Myocarditis
Myocardial contusion
Mitral valve prolapse

Pathophysiology
Normally, impulses pass through both ventricles almost at the same time and the depolarization waves of the two ventricles partially cancel each other out in the ECG.