Question 1

What are congenital anomalies?

Accepted Answer

Congenital anomalies (birth defects) are structural or functional abnormalities present from birth — affecting approximately 3-6% of births globally. They include structural anomalies (heart defects, neural tube defects, cleft lip/palate, limb defects), chromosomal anomalies (Down syndrome, Turner syndrome), metabolic disorders (phenylketonuria, congenital hypothyroidism) and functional disabilities. Major anomalies — those affecting function or requiring medical treatment — affect 6.1 million babies per year.

Question 2

What causes congenital anomalies?

Accepted Answer

Causes include: genetic factors (chromosomal abnormalities, single-gene mutations — account for approximately 30-40% of cases); infectious causes during pregnancy (rubella, CMV, toxoplasma, Zika virus causing foetal damage); nutritional factors (folate deficiency causing neural tube defects; iodine deficiency causing cretinism; vitamin A excess causing teratogenicity); medications (thalidomide, valproate, retinoids); environmental exposures (alcohol, tobacco, air pollution, pesticides); and unknown causes in approximately 50% of cases.

Question 3

How does folic acid prevent neural tube defects?

Accepted Answer

The neural tube — which forms the brain and spinal cord — closes within the first 28 days after conception, before most women know they are pregnant. Adequate folate is essential for this process. Periconceptional folic acid supplementation (400 μg/day, beginning at least one month before conception and continuing through the first trimester) reduces the risk of neural tube defects by 50-70%. Because closure occurs before pregnancy recognition, folic acid supplementation ideally begins before conception — or food fortification ensures all women of reproductive age have adequate folate.

Question 4

What is the global folic acid fortification situation?

Accepted Answer

Over 80 countries mandate folic acid fortification of flour — providing population-wide NTD prevention without requiring individual supplementation. Countries with mandatory fortification have seen 20-40% reductions in NTD prevalence. However, fortification coverage is uneven: many LMICs have voluntary rather than mandatory fortification; some populations rely on unfortified traditional flours. WHO strongly recommends mandatory folic acid food fortification in all countries.

Question 5

What are congenital heart defects?

Accepted Answer

Congenital heart defects (CHDs) are the most common major congenital anomaly — affecting approximately 8 per 1,000 live births (about 1.35 million births/year globally). The spectrum ranges from minor defects (small ventricular septal defects that may close spontaneously) to complex malformations requiring multiple surgeries. CHDs cause approximately 85,000 neonatal deaths per year — the largest single category of congenital anomaly deaths. Paediatric cardiac surgery can correct most CHDs but is unavailable in most LMICs.

Question 6

What is Down syndrome?

Accepted Answer

Down syndrome (Trisomy 21) — caused by an extra copy of chromosome 21 — is the most common chromosomal anomaly, affecting approximately 1 in 700 live births. It causes intellectual disability, characteristic facial features and increased risk of congenital heart defects (50%), acute leukaemia, hearing loss, and early-onset Alzheimer's disease (after 40). Life expectancy has increased from approximately 25 years in the 1980s to 60+ years in high-income countries with modern healthcare. Down syndrome is a human variation, not a disease — people with Down syndrome lead meaningful, fulfilling lives.

Question 7

What is newborn screening?

Accepted Answer

Newborn screening (NBS) uses a heel-prick blood spot taken within 24-72 hours of birth to screen for treatable metabolic, endocrine and haematological disorders. Early treatment prevents intellectual disability, disability and death in affected infants who appear healthy at birth. Standard screening in high-income countries covers 20-50+ conditions including: phenylketonuria (PKU); congenital hypothyroidism; cystic fibrosis; congenital adrenal hyperplasia; galactosaemia; and haemoglobin disorders (sickle cell). Most LMIC newborns receive no screening.

Question 8

How do infections during pregnancy cause birth defects?

Accepted Answer

Several infections during pregnancy cause congenital anomalies: rubella — congenital rubella syndrome (cataracts, hearing loss, cardiac defects) — the most important vaccine-preventable cause, now rare in countries with MMR vaccination; Zika virus — microcephaly and congenital Zika syndrome; cytomegalovirus (CMV) — the most common congenital infection globally, causing hearing loss and intellectual disability; toxoplasmosis — from cat faeces or undercooked meat — causing chorioretinitis and brain damage; and syphilis — causing stillbirth, neonatal death and severe disability.

Question 9

What teratogenic medicines should be avoided in pregnancy?

Accepted Answer

Several commonly used medicines are teratogenic: valproate (anti-epileptic) — causes neural tube defects, facial anomalies and autism spectrum disorder — the "valproate tragedy" has led to PRAC restrictions in the EU; thalidomide — causes limb reduction defects — now restricted to specific indications with strict REMS programmes; isotretinoin (acne treatment) — causes severe craniofacial, cardiac and CNS anomalies; warfarin — causes warfarin embryopathy; and ACE inhibitors — cause renal anomalies. Pre-conception counselling about teratogenic medicines is essential.

Question 10

What is the surgical care gap for congenital anomalies?

Accepted Answer

95% of children born with serious congenital anomalies in LMICs die in the first year of life — without access to surgical care that is routine in high-income countries. Paediatric cardiac surgery, cleft lip/palate repair, spina bifida management and orthopaedic surgery for club foot or limb defects are absent or extremely limited in most LMICs. Operation Smile, the Global Alliance for Surgery and Smile Train provide surgical access for some conditions — but the structural gap is enormous.

Question 11

How does Georgia manage congenital anomalies?

Accepted Answer

Georgia has made progress in newborn screening implementation, with a national NBS programme covering congenital hypothyroidism and PKU — conditions that were historically undetected and caused preventable intellectual disability. Folic acid supplementation campaigns have been implemented. PHIG's accreditation work addresses congenital anomaly detection and management standards in Georgian hospitals. The Georgian Medical Journal covers congenital anomaly epidemiology in the South Caucasus.

Question 12

How does GMJ News cover congenital anomalies?

Accepted Answer

GMJ News covers WHO congenital anomaly burden data, folic acid fortification policy, newborn screening programme expansion, rubella elimination progress, and the surgical care gap for birth defects. Congenital anomaly prevention and newborn screening are direct public health priorities for PHIG.

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