If OI is moderate or severe, healthcare providers usually diagnose it during prenatal ultrasound at 18 to 24 weeks of pregnancy.
If a parent or sibling has OI, a healthcare provider can test the DNA of the fetus for the presence of an OI mutation. In this case, a healthcare provider obtains a sample of fetal cells by chorionic villus sampling (CVS) or amniocentesis. The fetal cells can also be tested for the presence of abnormal collagen.
For amniocentesis, a healthcare provider takes a small amount of fluid from the sac surrounding the fetus for testing. He or she takes the sample by inserting a thin needle into the uterus through the abdomen. For CVS, a healthcare provider uses a similar procedure to take a sample of tissue from the placenta for testing.
If OI is not detected prenatally, parents or a healthcare provider may notice symptoms in an infant or child. The healthcare provider may perform the following:
- Physical exam, which includes:
- Measuring the length of limbs
- Measuring the head circumference
- Examining the eyes and teeth
- Examining the spine and rib cage
- Personal and family medical history, which include questions about:
- Broken bones
- Hearing loss
- Brittle teeth
- Adult height
- Racial background
- Whether close relatives have had children together
- Bone density test
- Bone biopsy, in some cases