What risks do women face with home births and no prenatal screening, including no ultrasounds (ultrasound imaging)?

Risks of Home Birth Without Prenatal Screening or Ultrasounds

Women who choose home births without any prenatal screening or ultrasounds face substantially increased risks of undetected fetal abnormalities, missed pregnancy complications, and elevated neonatal mortality—particularly when combined with the inherently higher perinatal death rates already associated with planned home births in the United States.

Undetected Chromosomal Abnormalities

Without prenatal screening, chromosomal abnormalities like Down syndrome (trisomy 21), trisomy 18, and trisomy 13 will go completely undetected until birth:

• First-trimester combined screening (nuchal translucency ultrasound + PAPP-A + hCG) detects approximately 70% of Down syndrome cases with a 5% false-positive rate 1
• Cell-free DNA screening achieves 99% detection for trisomy 21, making it the most accurate screening test available 1
• Sequential/integrated screening approaches detect 93% of trisomy 21 and 82% of all aneuploidies 1

By forgoing all screening, women lose the opportunity for informed decision-making about continuing the pregnancy or preparing for a child with special needs. This is particularly concerning because any woman of any age can have a fetus with chromosomal abnormalities 1.

Missed Structural Fetal Abnormalities

Ultrasound examination is critical for detecting major structural defects that significantly impact morbidity and mortality:

• Congenital heart defects are associated with increased nuchal translucency measurements and can be detected early 1
• Diaphragmatic hernias, skeletal dysplasias, and genetic syndromes present with ultrasound findings that would otherwise go undetected 1
• Neural tube defects require either maternal serum AFP screening or anatomic ultrasound survey between 16-20 weeks for detection 2

Without ultrasound, life-threatening conditions requiring immediate neonatal intervention or planned delivery at a tertiary center will be missed, resulting in preventable neonatal deaths or severe morbidity.

Unrecognized High-Risk Pregnancy Conditions

The absence of prenatal care means missing conditions that contraindicate home birth:

Absolute Contraindications That Will Go Undetected:

• Breech presentation (requires ultrasound confirmation) 3
• Multiple gestations (twins, triplets) 3
• Placenta previa or other placental abnormalities (requires ultrasound)
• Fetal growth restriction, particularly with low PAPP-A levels (<0.4 MoM) 2

Contraindicated home births are increasing in the United States (from 481 in 1990 to 1,396 in 2015), and these carry substantially elevated risks 3.

Elevated Neonatal Mortality Risk

The combination of home birth setting plus absence of screening creates compounded risks:

• Planned home births in the United States have a neonatal mortality rate of 13.66 per 10,000 live births compared to 3.27 per 10,000 for hospital midwife-attended births (odds ratio 4.19,95% CI 3.62-4.84) 4
• This 4-fold increased risk applies even to low-risk pregnancies 4, 5
• When risk factors are present (which would be unknown without screening), the mortality differences increase further 4
• Unintended/unplanned home births have even higher mortality at 27.98 per 10,000 live births 4

The increased mortality is attributed to deliveries of patients with unrecognized increased risks, absence of standardized criteria to exclude high-risk deliveries, and inadequate midwifery training standards in the United States 5.

Missed Maternal Health Risks

Without prenatal screening, maternal conditions affecting pregnancy outcomes go undetected:

• Toxoplasmosis infection during pregnancy has MTCT risk ranging from <5% early in pregnancy to 71% at 37 weeks, with prompt treatment reducing transmission by 52% 1
• Low PAPP-A levels (<0.4 MoM) indicate major risk for fetal growth restriction, warranting increased surveillance and aspirin prophylaxis 2
• Gestational diabetes, preeclampsia risk factors, and other medical conditions requiring monitoring will be missed

Inability to Optimize Pregnancy Outcomes

The absence of prenatal care eliminates opportunities for intervention:

• Aspirin prophylaxis (75-100 mg daily before 16 weeks) can prevent preeclampsia and growth restriction in high-risk patients 2
• Prompt treatment of maternal infections reduces vertical transmission 1
• Planned delivery at appropriate facilities for detected abnormalities improves neonatal outcomes
• Accurate pregnancy dating (critical for determining term vs preterm) requires early ultrasound

Critical Pitfalls and Caveats

The most dangerous scenario is combining home birth (already higher risk in the US) with complete absence of screening, because:

1. Risk factors that absolutely contraindicate home birth remain unknown
2. Conditions requiring immediate neonatal resuscitation or surgery are discovered only after delivery
3. The woman cannot provide truly informed consent about home birth risks without knowing her actual risk status
4. Transfer to hospital during labor for complications has worse outcomes than planned hospital delivery

Most concerning: Nearly all women choosing contraindicated home births receive prenatal care (>95%), suggesting they choose home birth despite knowing risks 3. Without any prenatal care, women cannot even make this informed choice.

The evidence is clear that hospital births should be supported for all patients, especially those with increased risks 5, but without screening, those increased risks remain invisible until potentially catastrophic outcomes occur.