Pregnancy is an incredibly dynamic process and the fetus is intimately attuned to its mother. It learns the day-night cycles from the rhythms of her sleep and activity. It knows her voice. The fetus comes to appreciate her taste in food. It is a powerful learning organism.
If the mother fails to provide vital nutrients, the fetus prepares for a world of scarcity, changing its metabolism to wring the most out of every calorie. Such a baby might be born with liver and pancreas with less capacity of processing fats and sugars, predisposing the adult to high cholesterol and diabetes. If mom‘s stress hormones are high, the baby prepares for a harsh world, recalibrating its nervous system to be on high alert for potential threats.
The womb experience prepares a child for emotional resilience and susceptibility to disease. Unfortunately, this experience is not always under the mother's control. If a woman is anxious for months on end, such as from a problematic marriage, work of financial strains, high levels of stress related cortisol may reach her fetus. Since the fetus's brain does not need as many receptors to sense the hormone's presence, it develops fewer.
Having fewer cortisol receptors can impair a person's ability to cope with the world, leading to greater wear and tear on the body and difficulty managing strong emotions without lashing out, withdrawing or becoming depressed. Infants of pregnant mothers who developed posttraumatic stress disorder after the 9/11 attacks were more easily upset by loud noises and unfamiliar people.
In this manner, temperament is not genetically determined but also affected by in utero exposure to the mother's mood. A large research program in England found that women who ranked in the top 15 percent for anxiety during pregnancy had children with double the rate of emotional and behavioral problems by the time they were 10 years old. In contrast, mild anxiety in the mother may have beneficial effects. Another study demonstrated that two year olds whose mothers were moderately anxious or depressed during pregnancy performed better on average on reasoning and coordination tasks.
Birth is a beginning, however, not an ending. Nurturing and mental stimulation can reverse the effects of a problematic pregnancy. Moms who are very turned into their newborns have babies with normal cortisol levels, no matter the mother's anxiety or depression prior to birth. If children learn good exercise and eating habits, they are unlikely to become obese or get diabetes. And if their parents and other caregivers engage and nurture them, they are less likely to develop learning or conduct disorders.
Dr. Weekley is a clinical psychologist practicing in Covington. He specializes in the treatment of adults for depression, anxiety, relationship problems and medical issues. He can be reached at (770) 441-9244.
