New research published in the Annals of Internal Medicine shows that undergoing a CT scan shortly before conception is associated with a modest increase in the risk of miscarriage, ectopic pregnancy, stillbirth, and congenital abnormalities. The closer the CT occurs to conception and the higher the number of scans, the greater the risk. Although women who received CT scans often had more underlying health conditions, researchers still found a potential association between preconception CT exposure and adverse pregnancy outcomes. Experts emphasize that CT scans remain essential when clinically indicated, but unnecessary radiation should be minimized, especially for women planning pregnancy.
Risk of Pregnancy Loss (after CT before conception):
- 1 CT scan: 8% increased risk
- 2 CT scans: 14% increased risk
- 3 or more CT scans: 19% increased risk
- CT performed 1–2 months before conception: 24% increased risk
Risk of Congenital Abnormalities (within the first year of life):
- 1 CT scan: 6% increased risk
- 2 CT scans: 11% increased risk
- 3 or more CT scans: 15% increased risk
Higher risk when CT scanned areas include:
- abdomen
- pelvis
- lower spine
Underlying health conditions more common in women who had CT scans:
- endometriosis
- pelvic inflammatory disease
- thyroid disorders
- hypertension
Expert Opinions:
- CT should still be used when medically necessary
- Unnecessary radiation exposure should be avoided
- For women planning pregnancy, alternative imaging (ultrasound, MRI) is preferable
- Clinicians should be more judicious in ordering CT scans
