(Reuters Health) - Young adults who were born prematurely may have weaker muscles than their peers born at full term, a Finnish study suggests.
These young adults born preterm also considered themselves less physically fit, even though the study didn’t find their cardiorespiratory fitness levels to be much different than people who weren’t born early.
Pregnancy normally lasts about 40 weeks, and babies born after 37 weeks are considered full term. In the weeks immediately after birth, preemies often have difficulty breathing and digesting food. Some premature infants also encounter longer-term challenges such as impaired vision, hearing, and cognitive skills as well as social and behavioral problems.
Previous research has also found that the tiniest and most immature preemies may have poor muscular fitness. But the current study is important because it suggests that this problem may extend to all pre-term babies, even those who are only slightly early or a little bit underweight, said lead author Dr. Marjaana Tikanmaki of the National Institute for Health and Welfare and University of Oulu in Finland.
“The differences in muscular fitness of young adults born preterm were detected in our study across the full range of preterm birth, but not for cardiovascular fitness,” Tikanmaki said by email.
But, Tikanmaki added, “The test we used to measure cardiovascular fitness may not be sensitive enough to detect small differences between those born preterm and those born at term.”
To see how the timing of birth might impact fitness later in life, the researchers studied 139 young adults born before 34 weeks gestation, which is considered early preterm, as well as 247 people born from 34 to 36 weeks, or late preterm. They compared these individuals to a control group of 352 full term individuals.
On average, the participants were around 23 years old.
Researchers assessed muscular fitness based on the number of modified push-ups performed in 40 seconds, a test that measures short-term endurance capacity of the upper body and the ability to stabilize the trunk.
On average, women did about 10 push-ups and men managed about 14. But the people who were born preterm typically did about one less push-up than their full-term peers.
In another assessment of muscular fitness, researchers also examined grip strength based on how hard people could squeeze a force-measuring device with their dominant hand.
With this test, people born early preterm didn’t do as well as those born late preterm or full term.
To check cardiorespiratory fitness, researchers asked participants to step on and off a bench at a set pace for four minutes.
By the end of this test, the average heart rate for women was 160 beats a minute, while it was 153 beats a minute for the men. There wasn’t a difference based on the timing of birth.
Researchers also asked participants to rate their own fitness, from 1 to 5, with higher scores for better abilities in this area. Average scores were 2.3 for women and 2.6 for men.
The early preterm people typically scored themselves about 0.2 points lower than full-term participants, and higher scores were linked to better measurements of physical fitness, the researchers reported in the journal Pediatrics.
One limitation of the study is that the cardiorespiratory fitness test didn’t necessarily push people to their maximum ability, a type of exercise that often takes longer and may gradually increase in difficulty until participants can no longer continue.
It’s also possible that these relatively young participants may have been too fit relative to older adults to detect large differences in their cardiovascular health, Tikanmaki noted.
Even so, the results highlight the importance of focusing on heart health early in life to ward off potential problems down the line, noted Dr. Ravi Shah, a researcher at Harvard Medical School in Boston who wasn’t involved in the study.
“These findings support efforts to reduce obesity and improve physical fitness throughout early life, though any specific recommendations regarding exercise should be individualized and undertaken only after counseling from a physician,” Shah said by email.
SOURCE: bit.ly/1QY3kYT Pediatrics, online December 29, 2015.
"At 17 weeks pregnant, I was told my baby was going to die. He was very small and wasn't able to get enough nutrients to grow. I wasn't going to give up on my baby, so I was very closely monitored. Jonah was born on Nov. 7, 2014 weighing two pounds, three ounces. He stayed in the NICU, an hour away from my house, for 78 days. He is now a year old and 14 pounds. Still small, but he's growing at his own little pace. He's been through a lot in his life already. He's my little miracle fighter."
"Both of my babies were preemies, and so our experiences with the NICU staff will always be something I'll remember. Our daughter was born six and a half weeks early, and although healthier at birth than her brother, both still dropped to three pounds, 12 ounces. She's the light of our world and the two make the perfect pair to our family."
"My son Elijah was born at 30 weeks, one day. My water broke when I was just 24 weeks pregnant and I had to stay on hospital bedrest for six weeks before he came. Due to intrauterine growth restraint (also known as IUGR), he weighed one pound, 12 ounces at birth and was 11 inches long. He spent 91 days in the NICU. It was such an emotional roller coaster but we are so grateful that he is alive and thriving! He is now two years old. Aside from being lactose intolerant, he is doing fantastic! He's a growing and active toddler!"
"My Talan was born 9 years ago at 26 weeks and two pounds, five ounces. He spent two months in the NICU and did exceptionally well. He overcame the usual holes in heart, brain bleeding, tube feeding and Apnea spells. After reaching four pounds and coming home, he also had to deal with torticollous and speech delay, but both were cleared up with therapy. Now, he is extremely healthy and intelligent, a star soccer player and in the gifted class at school. We are so blessed and thankful to have such a great story to share. Miracles do happen everyday."
"Drew was born at 35 weeks. His lungs were failing him and he had a stay in the NICU. It was the longest two weeks for my husband and I. While in the NICU, he developed jaundice and had to stay a little longer. The day we brought him home was the best. He's now a happy, healthy 6-year-old boy who is full of energy and is the apple of his daddy's eye. I thank God every day for our little preemie!"
"My twin girls, Stevie and Harper, were born at 34 weeks and spent three weeks in the NICU. They had difficulty breathing, maintaining body temperature and eating. We were so lucky to have the NICU staff to help guide us through the process. We are so blessed that our girls are now 10 months old and thriving. They are almost on target for the average 10 month old."
Jessica Koegler Yeager
"Jack is ten now. He was born six weeks early and spent three weeks in the NICU."
"Our baby boy Bodie was born at 34 weeks and weighed four pounds, 8 ounces. I was diagnosed with a condition called uterine didelphys during some of our first ultrasounds. Bodie is our miracle baby, as there is a huge miscarriage rate with this condition. We knew there were high chances of Bodie being born early as well. Luckily we only spent 18 days in the NICU. We now have a hefty and healthy 6-month-old who is officially off the preemie charts."
"My son Parker was born on July 9, 2006 at 30 weeks. He was two pounds, 13 ounces. He spent 49 days in the NICU. Having a baby that ends up in the NICU is simultaneously the best and worst time of your life. Even after you come home from the NICU, there are challenges. He is such a warrior -- he is now 9 and in fourth grade. He has developed into such a strong and amazing young man.He is small for his age, but he tells everyone who comments on his size that he is just 'fun size.'"
"This is my son, Jesse. He was born when I was 25 weeks and six days pregnant. He weighed two pounds, two ounces and measured 13.5 inches, at one point dropping in weight to one pound, 11 ounces. He spent 66 days in the NICU with a few ups and downs, and a few more when he came home, but he's doing awesome now! He's nine months old and weighs in at 15 pounds, 12 ounces, 24.5 inches. He had a rough entrance into the world but now he's ready to take it on!"
"Elliott was born eight weeks premature at just about 32 weeks after my water broke at 28 weeks. He was born at three pounds, three ounces and was 16 inches long. He spent six weeks in the NICU, and eventually came home on oxygen. He is now almost 15 months old and catching up wonderfully and thriving."
"Both of my babies were preemies, and so our experiences with the NICU staff will always be something I'll remember. Our son, who was eight-plus weeks early is a thriving 6-year-old and a constant ball of energy in motion."
"I have a unique set of twins that were born at exactly 33 weeks. They stayed 24 and 34 days in the NICU. To our surprise, Maxwell (Baby B), was born with albinism while his twin brother Miles was not.They had challenges in the beginning of their lives and came home on apnea monitors. But they are normal happy, healthy and amazing 2-year-olds now."
"This is my son, my miracle! He was delivered via emergency C-section at 26 weeks after I developed HELLP syndrome. Weighing only 550 grams, he suffered numerous complications and spent 157 days in the NICU. He is now 9 and I am in absolute awe of the person he is! He is my constant reminder that miracles do happen!"
"My twins, Breckin and Cameron, were born at 30 weeks. They were three pounds, one ounce at birth and stayed in the NICU for 54 days. Today, they are healthy, happy and thriving 21-month-old boys!"
"My son Luke was born at 29 weeks, six days. He weighed just under two pounds and was 13 inches long. At 3 years old, he's now a happy, funny, dancing maniac!"
"My daughter Makenzie was born 11 weeks early and weighed two pounds, 12 ounces. She spent 45 days in the NICU. She is a happy, smart little girl who will turn 4 on December 1! Unfortunately, because she was born too soon she now suffers from cerebral palsy. She is unable to walk by herself but we are diligent with her therapies and making sure she receives every opportunity possible to thrive! My daughter is a joy and inspiration to me every single day. I am so proud to be her mother and share our journey as a preemie family and also a special needs family."
"Seth Thomas Pender Jr. was born Aug. 2, 2015 at 33 weeks. He was in the neonatal intensive care unit for 16 long days. At birth he weighed five pounds, seven ounces. While in the NICU his weight dropped to four pounds, 11 ounces. Seth is now 3.5 months old and a very healthy, happy boy!"
"This is my daughter, Bay Olivia. She was born eight weeks premature. She faced many of the common problems premature babies face. She suffered with reflux until she was about 1. One other, less common problem she faced was a life-threatening polyp unknowingly growing on her vocal cord for the eight weeks she was in the NICU. She is now 2 and is as healthy as she can be!!! She brings joy to our whole family. She is our very own miracle."
"Jasper was born five weeks early on Aug. 29, 2010. He was in the NICU not for being underweight or underdeveloped, but he had a hole in his lung, that wasn't discovered until 2 a.m. on the morning that we were to be discharged. It was truly a miracle that it was found before we went home. As terrifying as the whole situation and experience was, we are extremely blessed that things happened the way that they did. He is now a thriving 5-year-old with no limits to the future. Such a loving, old soul that makes my heart smile every single day."
"Born in July at 32 weeks, and yesterday next to her NICU octopus."
"My little boy Junior was born at 28 weeks; he weighed two pounds, eight ounces. He was in the NICU for two weeks, and he went on CPAP for a week and then came off that. Then a week later he needed to be put on oxygen -- he spent two weeks there, then went back to a special care unit and continued on oxygen. Junior had a hole in his heart but it closed up when he was about four months old. He was in hospital from birth -- Jan. 22, 2015 -- until Mar. 30. Once he came home it was all a distant memory -- he is now 10 months old. He crawls, he tries to copy words. And his weight is 21 pounds now -- he's caught up to children who were full term. He has done amazing, and I'm so proud if him. He always will be my miracle."
"Ryker was born a month early after my month-and-a-half-long stay in the hospital. We had high blood sugar and low fluid. He was having a hard time breathing and eating. Ryker was in the hospital about two weeks before I could bring him home. He is so amazing, smart and funny."