For most cases the diagnosis for congenital amputation is not made until the infant is born. One procedure that is helpful in determining this condition in an infant is an ultrasound examination of a fetus when still in the mother's abdomen as it can reveal the absence of a limb. However, since ultrasounds are routine they may not pick up all the signs of some of the more subtle birth defects.

The most popular method of treatment for congenital amputation is having the child be fit for a prosthesis which can lead to normal development, so the muscles don't atrophy. If there is congenital amputation of the fingers, plastic surgery can be performed by using the big toe or second toes in place of the missing fingers of the hand.

In rare cases of amniotic banding syndrome, if diagnosed "in utero", fetal surgery may be considered to save a limb which is in danger of amputation.

Studies suggest that prenatal care for mothers during their pregnancies can prevent congenital amputation. Knowing environmental and genetic risks is also important. Heavy exposure to chemicals, smoking, alcohol, poor diet, or engaging in any other teratogenic activities while pregnant can increase the risk of having a child born with a congenital amputation. Folic acid is a multivitamin that has been found to reduce birth defects.

Carrier testing for Roberts syndrome requires prior identification of the disease-causing mutation in the family. Carriers for the disorder are heterozygotes due to the autosomal recessive nature of the disease. Carriers are also not at risk for contracting Roberts syndrome themselves. A prenatal diagnosis of Roberts syndrome requires an ultrasound examination paired with cytogenetic testing or prior identification of the disease-causing ESCO2 mutations in the family.

Ectromelia is a congenital condition where long bones are missing or underdeveloped.

Examples include:

- Amelia

- Hemimelia

- Phocomelia

- Sirenomelia

Prosthesis is a synthetic alternative for missing limbs, teeth, and various other body parts. Advances in prosthetic limbs have increased greatly during the twentieth century. The use of new materials such as modern plastics, complex procedures and better pigments have created lighter in weight and more realistic looking artificial limbs. With the advancement of myoelectric prosthetic limbs, patients are able to move their limbs without the use of cords or other devices. The myoelectric limbs can detect electric signals from the nervous system and muscles. They were first used on adults, but now they are being fitted to children.

Patients that receive a loss of limbs due to phocomelia are typically treated with prosthetics. Infants at the age of 6 months are recommended to have a prosthetic mitten fitted; enabling them to get used to the prosthesis. A hook will be added when the child reaches the age of 2 years. Eventually the patient may receive a myoelectric prosthetic limb. Patients are treated in this way due to the lack of understanding at a young age and the absence of necessary tissues and bones to hold the prosthetic limb.

Dysmelia can be caused by

- inheritance of abnormal genes, e.g. polydactyly, ectrodactyly or brachydactyly, symptoms of deformed limbs then often occur in combination with other symptoms (syndromes)

- external causes during pregnancy (thus not inherited), e.g. via amniotic band syndrome

- teratogenic drugs (e.g. thalidomide, which causes phocomelia) or environmental chemicals

- ionizing radiation (nuclear weapons, radioiodine, radiation therapy)

- infections

- metabolic imbalance

Cytogenetic preparations that have been stained by either Giemsa or C-banding techniques will show two characteristic chromosomal abnormalities. The first chromosomal abnormality is called premature centromere separation (PCS) and is the most likely pathogenic mechanism for Roberts syndrome. Chromosomes that have PCS will have their centromeres separate during metaphase rather than anaphase (one phase earlier than normal chromosomes). The second chromosomal abnormality is called heterochromatin repulsion (HR). Chromosomes that have HR experience separation of the heterochromatic regions during metaphase. Chromosomes with these two abnormalities will display a "railroad track" appearance because of the absence of primary constriction and repulsion at the heterochromatic regions. The heterochromatic regions are the areas near the centromeres and nucleolar organizers. Carrier status cannot be determined by cytogenetic testing. Other common findings of cytogenetic testing on Roberts syndrome patients are listed below.

- Aneuploidy- the occurrence of one or more extra or missing chromosomes

- Micronucleation- nucleus is smaller than normal

- Multilobulated Nuclei- the nucleus has more than one lobe

Dysmelia can refer to

- missing (aplasia) limbs: amelia, oligodactyly, congenital amputation e.g. Tibial or Radial aplasia

- malformation of limbs: shortening (micromelia, rhizomelia or mesomelia), ectrodactyly, phocomelia, meromelia, syndactyly, brachydactyly, club foot

- too many limbs: polymelia, polydactyly, polysyndactyly

- others: Tetraamelia, hemimelia, Symbrachydactyly

Although significant progress has been made in identifying the etiology of some birth defects, approximately 65% have no known or identifiable cause. These are referred to as sporadic, a term that implies an unknown cause, random occurrence regardless of maternal living conditions, and a low recurrence risk for future children. For 20-25% of anomalies there seems to be a "multifactorial" cause, meaning a complex interaction of multiple minor genetic anomalies with environmental risk factors. Another 10–13% of anomalies have a purely environmental cause (e.g. infections, illness, or drug abuse in the mother). Only 12–25% of anomalies have a purely genetic cause. Of these, the majority are chromosomal anomalies.

Congenital anomalies resulted in about 632,000 deaths per year in 2013 down from 751,000 in 1990. The type with the greatest death are congenital heart disease (323,000), followed by neural tube defects (69,000).

Many studies have found that the frequency of occurrence of certain congenital malformations depends on the sex of the child (table). For example, pyloric stenosis occurs more often in males while congenital hip dislocation is four to five times more likely to occur in females. Among children with one kidney, there are approximately twice as many males, whereas among children with three kidneys there are approximately 2.5 times more females. The same pattern is observed among infants with excessive number of ribs, vertebrae, teeth and other organs which in a process of evolution have undergone reduction—among them there are more females. Contrarily, among the infants with their scarcity, there are more males. Anencephaly is shown to occur approximately twice as frequently in females. The number of boys born with 6 fingers is two times higher than the number of girls. Now various techniques are available to detect congenital anomalies in fetus before birth.

About 3% of newborns have a "major physical anomaly", meaning a physical anomaly that has cosmetic or functional significance.

Physical congenital abnormalities are the leading cause of infant mortality in the United States, accounting for more than 20% of all infant deaths. Seven to ten percent of all children will require extensive medical care to diagnose or treat a birth defect.

- Data obtained on opposite-sex twins. ** — Data were obtained in the period 1983–1994.

P. M. Rajewski and A. L. Sherman (1976) have analyzed the frequency of congenital anomalies in relation to the system of the organism. Prevalence of men was recorded for the anomalies of phylogenetically younger organs and systems.

In respect of an etiology, sexual distinctions can be divided on appearing before and after differentiation of male's gonads in during embryonic development, which begins from eighteenth week. The testosterone level in male embryos thus raises considerably. The subsequent hormonal and physiological distinctions of male and female embryos can explain some sexual differences in frequency of congenital defects. It is difficult to explain the observed differences in the frequency of birth defects between the sexes by the details of the reproductive functions or the influence of environmental and social factors.

Ear agenesis is a medical condition in which people are born without ears.

Because the middle and inner ears are necessary for hearing, people with complete agenesis of the ears are totally deaf. Minor agenesis that affects only the visible parts of the outer ear, which may be called microtia, typically produces cosmetic concerns and perhaps hearing impairment if the opening to the ear canal is blocked, but not deafness.

Phocomelia is a condition that involves malformations of the arms and legs. Although many factors can cause phocomelia, the prominent roots come from the use of the drug thalidomide and from genetic inheritance. Occurrence in an individual results in various abnormalities to the face, limbs, ears, nose, vessels and many other underdevelopments. Although operations may improve some abnormalities, many are not surgically treatable due to the lack of nerves and other related structures.

The term is from Ancient Greek φώκη "phōkē", "seal (animal)" + "-o-" interfix + μέλος "melos", "limb" + English suffix "-ia") is an extremely rare congenital disorder involving malformation of the limbs (dysmelia). Étienne Geoffroy Saint-Hilaire coined the term in 1836.

Eye agenesis is a medical condition in which people are born with no eyes.

RL syndrome is characterized by renal dysplasia, growth retardation, phocomelia or mesomelia, radiohumeral fusion (joining of radius and humerus), rib abnormalities, anomalies of the external genitalia and potter-like facies among many others.

Renal dysplasia-limb defects syndrome (RL syndrome), also known as Ulbright–Hodes syndrome, is a very rare autosomal recessive congenital disorder. It has been described in three infants, all of whom died shortly after birth.

A unibrow is part of normal human variation, but can also stem from developmental disorders. A unibrow is a recognized feature of Cornelia De Lange syndrome, a genetic disorder whose main features include moderate to severe learning difficulties, limb abnormalities such as oligodactyly (fewer than normal fingers or toes) and phocomelia (malformed limbs), and facial abnormalities including a long philtrum (the slight depression/line between the nose and mouth).

Other medical conditions associated with a unibrow include:

- Waardenburg Syndrome;

- Patau Syndrome;

- Smith-Lemli-Opitz Syndrome;

- Sanfilippo Syndrome;

- 3p Deletion Syndrome;

- Chromosome Deletion Dillan 4p Syndrome (Wolf–Hirschhorn Syndrome);

- Gorlin Syndrome (Basal Cell Nevus Syndrome);

- Frontometaphyseal Dysplasia;

- ATRX Syndrome;

- Chromosome 9q34 Microdeletion Syndrome or Kleefstra syndrome.

A unibrow (or monobrow; called synophrys in medicine) is a single eyebrow created when the two eyebrows meet in the middle above the bridge of the nose. The hair above the bridge of the nose is usually of the same color and thickness as the eyebrows, giving the appearance that they converge to form one uninterrupted line of hair.

Common investigations include blood urea nitrogen (BUN) and electrolytes, liver function tests, urinalysis, and thyroid function tests. Hematological investigations include hematocrit levels, which are usually raised in HG. An ultrasound scan may be needed to know gestational status and to exclude molar or partial molar pregnancy.

Hyperemesis gravidarum is considered a diagnosis of exclusion. HG can be associated with serious problems in the mother or baby, such as Wernicke's encephalopathy, coagulopathy, peripheral neuropathy.

Women experiencing hyperemesis gravidarum often are dehydrated and lose weight despite efforts to eat. The onset of the nausea and vomiting in hyperemesis gravidarum is typically before the twenty-second week of pregnancy.