Just nine short weeks after conception, your baby’s head is responsible for half of his or her length. But there’s no need to worry, due to rapid growth during the upcoming weeks, your baby’s body will soon catch up. Your baby’s eyes are shut and quite apart but may respond to a dazzling brightness on mommy’s tummy. Your baby’s ears are lower during this trimester but will eventually rise to their normal birth position in the weeks ahead. Red blood cells are beginning to form in your baby’s liver. Reproductive organs, although appearing similar in both sexes and among the last to develop, are present. Ovaries are present in girls; testes are present in boys’ abdomens. It is during this week that your baby advances from embryo to fetus status. From now until 20 weeks (your halfway point), your baby’s weight will increase by 30% and his or her length will triple. By now, your baby roughly measures about 2 inches in length and weighs almost one third of an ounce.
At this time, ask your health care team if a Nuchal Translucency Screening (NTS) should be performed, as this test is not routinely performed in many states. This screening consists of a blood test and an ultrasound. Administered between Weeks 11-13, this screening for chromosomal abnormalities gives families important information on potential outcomes as early as possible. First trimester screening results can be combined with second trimester screen results to detect Down syndrome and Trisomy 18. This testing provides an estimate of risk only. A positive result, which indicates an increased risk, does not mean your baby has a problem.
During this screening, an ultrasound will measure the fluid accumulation behind the neck of the baby, called the nuchal translucency (NT). Extra fluid, (an increased NT) can be a sign of Down syndrome, Trisomy 18 or Trisomy 13.
Increased nuchal translucency has also been associated with other fetal anomalies such as cardiac defects. A second trimester fetal anatomy ultrasound and echocardiogram are recommended if the NT is increased.