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ACOG Recognizes the Fourth Trimester

Originally posted October 10, 2018.

In May of 2018, the American College of Obstetricians and Gynecologists (ACOG) expanded the definition of postpartum care of mom and baby and embraced the inclusive concept of the “fourth trimester.” For decades, American mom-baby advocacy groups have used the fourth trimester as a way to conceptualize newborn care in the first three months. And now ACOG validates and identifies this conceptualization of the fourth trimester as a sensitive period of development for both mom and baby.

Since the 1950’s, the mom-baby advocacy groups, such as La Leche League, conceptualized newborn parenting in the fourth trimester as informed by the human evolutionary scale. They normalize baby’s crying by framing it as a signal to be picked up and comforted by his or her caregivers. La Leche League says that it’s normal to provide comfort for a newborn baby by way of nursing, carrying and co-sleeping. All these behaviors imitate the womb environment of warmth, movement and lots of touch. La Leche League normalizes that a baby’s crying is his or her way of communicating with and connecting with their loved ones, and is not a form of manipulation. La Leche League says “It’s normal to ‘Pick the baby up!’ ” Using the construct of the fourth trimester, La Leche League is a positive community intervention for education about and parenting the newborn.

In 2003, Dr. Harvey Karp, a pedicatrician, was one of the first doctors to popularize the concept of the fourth trimester when he published his book, Happiest Baby on the Block. In his book, Dr. Karp explicitly discusses the fourth trimester as an extension of the three trimesters of pregnancy. During nine months of pregnancy, there is, of course, unbelievable complex development. What Dr. Karp brings in is the information archeologists have pieced together about evolving human brain development. As humans evolved, our brains become larger and more complex. At birth, the newborn does not have all brain structures fully developed. This way, the baby’s head can fit through mom’s birth canal. After birth, the baby gets down to the business of growing body and brain. And early humans used slings to carry their young with them. Primitive cultures still in existence today give us a glimpse into the parenting practices of early humans. The !Kung is one such culture that practices the traditional methods of hunting, gathering and carrying their young while working.

Eventually, the fourth trimester began to be defined as a time of healing for both mother and baby as research revealed a high prevalence of women’s postpartum physical and mental discomforts. The past few decades of research revealed postpartum women suffer from high rates of perinatal mood disorders and also physical disorders of the pelvic floor. These two important areas of postpartum mindbody care are treatable if identified properly and then referred to mental heath professionals and physical therapists specializing in care for postpartum women.

This new focus on the fourth trimester by the American organization, ACOG, as a special time of rest, growth and development is a good thing. Perhaps we can borrow some ideas for the fourth trimester from other cultures and give them an American flavor? In Britain, for example, their National Health System, sends specially trained nurses out for home visits in the postpartum period to check up on both mom and baby. In China, “doing the month” is a formalized period of time when postpartum women are cared for by extended family members. When doing the month, postpartum women rest and eat specific foods to heal from childbirth and delay re-joining the bustle of everyday life.

Latest research indicates that postpartum women need personalized, non-judgmental support that meets their individualized needs. In a country such as the US, where extended families are scattered and there is dwindling support for postpartum women, it is great news that ACOG has chosen to redefine and enhance our understanding of the postpartum period. ACOG sees the fourth trimester as a time when both mother and baby need ongoing care at least for the 12 weeks after delivery.

ACOG’s position helps move the narrative in American culture towards more compassionate care for both mothers babies and families.


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