Heidelise Als, Ph.D., a developmental psychologist at Harvard Medical School, is fascinated by the amount of tactile stimulation a fetus gives itself. Als believes there is a mismatch between the environment given to preemies in hospitals and the environment they would have had in the womb. She has been working for years to change the care given to preemies so that they can curl up, bring their knees together, and touch things with their hands as they would have for weeks in the womb. Laterborns may have more room in the womb for such maneuvers than first babies. After the initial pregnancy, a woman's uterus is bigger and the umbilical cord longer, allowing more freedom of movement.
Fetuses react sharply to their mother's actions.
When mothers watch this on the screen, they laugh harder, and the fetus goes up and down even faster. We've wondered whether this is why people grow up liking roller coasters. Why people grow up liking hot chilies or spicy curries may also have something to do with the fetal environment. By 13 to 15 weeks a fetus' taste buds already look like a mature adult's, and doctors know that the amniotic fluid that surrounds it can smell strongly of curry, cumin, garlic, onion and other essences from a mother's diet. Whether or not a fetus can taste, there's little question that it can hear.