Ask the doctors: Moms need support during ‘fourth trimester’
Q: My daughter and my daughter-in-law got pregnant at the same time. They just had their babies, and something that keeps coming up is the idea of the fourth trimester. That's not a term that was used when I had my own children, and I would like to learn more.
A: As most people probably know, the 40 weeks of pregnancy are divided into trimesters. These periods of about 13 or 14 weeks each are a way to track the developmental milestones of the growing fetus and the arc of pregnancy in the woman as well.
With the birth of the baby, the pregnancy has technically ended, but significant changes to the mother's body continue for several months. With the arrival of the baby and their needs, this postpartum period for the mother often goes unaddressed. This has given rise to the idea of the fourth trimester.
In addition to recovering from the physical and emotional rigors of giving birth, the mother's body is now undergoing rapid hormonal shifts. As her uterus returns to prepregnancy size, she often experiences spasms and cramping, which can become severe. With the birth of the baby, milk production begins. This can make breasts heavy, tight and tender.
Meanwhile, the swift retreat of pregnancy hormones can lead to hair loss, vaginal dryness and night sweats. Persistent fatigue is common. The risk of postpartum depression increases at this time.
The idea of the fourth trimester applies to the infant as well. Those first 12 weeks of life outside of the womb bring seismic changes. The newborn must learn to eat, develop sleep patterns, manage temperature changes, adjust to the physical sensations of being touched, and even learn the basics of the weight of gravity. And for both mother and infant, forming a bond is important.
The numerous changes that take place throughout the fourth trimester translate into a need for preparation, a network of supportive care and ongoing awareness. This means helping the woman in her physical, mental and emotional recovery. Family and friends can make sure she gets enough rest, eats a healthy diet and drinks enough water.
There are many ways to lend a hand. Managing well-wishers by keeping visits short can be helpful to a tired mom. Volunteering to shop, clean, do laundry, change diapers and soothe a crying baby can make the postpartum period less challenging. Also important is to watch for warning signs of emotional distress. If she needs any support with mental health, help her get the help she needs.
Baby blues, which is a hormone-driven letdown after birth, is estimated to affect up to three-fourths of new mothers. These symptoms typically ease within the first few weeks. If they continue — or if they grow more severe — it may be a sign of postpartum depression. This is a condition that requires medical care.
The fourth trimester is about the physical and emotional changes in the first months after giving birth and helping the new mother navigate them.
• Dr. Eve Glazier is an internist and associate professor of medicine at UCLA Health. Dr. Elizabeth Ko is an internist and assistant professor of medicine at UCLA Health. Send your questions to askthedoctors@mednet.ucla.edu.
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