Table 4 Risk of recurrent congenital anomaly in the second pregnancy (from any group, from the same group, from a different group) presented as natural frequency, by congenital anomaly group/subtype in the first pregnancy

Isolated anomalies

1 in 28

(24-32)

1 in 58

(48-75)

1 in 54

(44-69)

Nervous system

1 in 25

(18-35)

1 in 53

(32-90)

1 in 47

(29-68 ^b )

Neural tube defects

1 in 30

(19-49)

1 in 54

(28-103)

1 in 65^a

(33-65^b)

Anencephaly

1 in 26

(13-52)

1 in 69

(23-215)

1 in 41

(17-63^b)

Spina bifida

1 in 40

(18-61^b)

1 in 60

(23-161)

Hydrocephalus

1 in 20

(9-47)

1 in 25

(10-62^b)

Microcephaly

1 in 10

(5-25)

1 in 17

(6-54)

Cardiovascular

1 in 29

(23-36)

1 in 51

(38-68)

1 in 67 ^a

(48-92)

Ventricular septal defect (VSD)

1 in 25

(19-35)

1 in 42

(28-63)

1 in 64^a

(39-71^b)

Atrial septal defect (ASD)

1 in 21

(11-41)

1 in 27

(13-61)

Pulmonary valve stenosis

1 in 49

(19-61^b)

1 in 66

(22-205)

Aortic valve atresia/stenosis

1 in 33

(11-61^b)

1 in 50

(13-201)

Coarctation of the aorta

1 in 30

(12-61^b)

1 in 41

(13-127)

Orofacial clefts

1 in 28

(17-48)

1 in 50

(25-99)

1 in 64 ^a

(30-64 ^b )

Cleft lip

1 in 26

(10-61^b)

1 in 34

(12-62^b)

Cleft lip and palate

1 in 26

(12-57)

1 in 31

(13-74)

Cleft palate

1 in 28

(12-61^b)

1 in 47

(16-62^b)

Digestive system

1 in 31

(18-54)

1 in 93

(35-246)

1 in 46

(23-64 ^b )

Diaphragmatic hernia

1 in 16

(7-38)

1 in 26

(9-62^b)

Abdominal wall

1 in 61 ^a

(24-61 ^b )

1 in 62 ^a

(28-62 ^b )

Gastroschisis

1 in 57

(19-61^b)

1 in 62^a

(22-62^b)

Urinary

1 in 22

(16-31)

1 in 47

(29-76)

1 in 42

(26-66 ^b )

Cystic kidney disease

1 in 18

(9-36)

1 in 29

(12-70)

1 in 48

(16-63^b)

Limb

1 in 49

(21-61 ^b )

1 in 61 ^a

(23-62 ^b )

Polydactyly

1 in 14

(4-55)

1 in 14

(4-55)

Musculoskeletal

1 in 12

(5-31)

1 in 12

(5-31)

Syndromic anomalies

1 in 19

(15-22)

1 in 35

(28-48)

1 in 40

(31-55)

Chromosomal syndromes

1 in 23

(17-30)

1 in 37

(26-53)

1 in 59

(37-75 ^b )

Down syndrome

1 in 36

(22-59)

1 in 77

(37-160)

1 in 67^a

(34-67^b)

Edward syndrome

1 in 23

(9-61)

Turner syndrome

1 in 24

(9-61^b)

Genetic syndromes and microdeletions

1 in 11

(8-15)

1 in 18

(12-29)

1 in 26

(15-44)

DiGeorge syndrome

1 in 12

(5-29)

1 in 15

(6-40)

Stickler syndrome

1 in 2

(1-8)

1 in 2

(1-8)

Other syndromes, sequences, etc.

1 in 23

(12-43)

1 in 70

(23-216)

1 in 34

(16-63 ^b )

Other genetic anomalies

1 in 6

(3-13)

1 in 7

(3-17)

Multiple congenital anomalies

1 in 21

(13-35)

1 in 25

(15-41)

Any congenital anomaly

1 in 24

(22-27)

1 in 49

(42-59)

1 in 49

(42-59)