Maternal Intravenous Fluids During Labor and Newborn Weight Loss
by Anne Eglash MD, IBCLC, FABM
After covering SARS-CoV-2 in the last few CQWs, I thought I would take a break and discuss something germane, like weight loss, and then realized that with the changes we are witnessing in newborn care, this an important topic to highlight. Many new dyads are being discharged from the hospital after 24 hours for an uncomplicated vaginal delivery, and 48 hours after a cesarean birth, to reduce exposure of families to COVID-19 and to save on personal protective equipment for health care workers. In some communities it is harder for families to find follow-up care because physician offices are trying to keep people with non-urgent problems out of the office. A new mother recently shared with me that she was advised to supplement with formula at the time of hospital discharge to prevent the need for frequent weight checks.
Many lactation specialists have observed for years that infants born to mothers who have received copious IV fluid during labor appear to lose excessive weight despite breastfeeding well. I personally have seen infants with 10-12% weight loss at 24 hours.
The study for this week’s CQW is a French study that was retrospective, evaluating the relationship between maternal IV fluid and newborn weight loss. The researchers studied 150 records of patients who were low risk and gave birth to a single term healthy breastfeeding infant in 2016. They reviewed the amount of IV fluid given to the mothers, and correlated this with the newborn weights done from birth thru day 4.
The researchers found that when mothers received at least 1500ml of IV fluids, there was a greater likelihood of an 8% newborn weight loss at 72 hours.
Interestingly, they state that the French Society of Anesthesia and Intensive Care does not recommend IV fluids before an epidural to prevent a drop in maternal blood pressure, but 85% of mothers who received an epidural received at least 1500 ml of IV fluid.
I realize that this is not the first study done on this topic, and the results corroborate the findings in similar previous studies.
- Mothers who underwent an emergency cesarean were at higher risk for increased IV fluids.
- Longer labor was associated with more IV fluids.
- Mothers with a higher BMI received more IV fluids.
- Mothers receiving pitocin/oxytocin during labor received more IV fluids.
See the Answer
The main purpose of our study has been to establish a link between the administration of intravenous fluids during Labor and the weight loss experienced by infants during hospitalization.
We conducted a retrospective observational study using a descriptive and comparative method. We studied 150 records of patients who gave birth at term (low-risk pregnancy) of a single healthy new born with breastfeeding in a university hospital center between 1 January 2016 and 31 July 2016. Maternal, obstetrical and neonatal characteristics were registered to determine the influence of vascular filling by univariate and multivariate analysis and identified factors that may lead to increase neonatal weight loss.
One hundred and fifty mother–child couples were studied. Newborns whom mothers received at least 1500mL of solute during Labor lose significantly more weight until the third day of life (p<.001) compared to women who received less than 1500 mL, also observed for neonatal weight loss greater than 8% (p=.043). In addition, the obstetrical factors most significantly associated with an increase in the volume of solute injected were the duration of Labor (p<.001), the administration of oxytocin (p<.001), epidural analgesia (p=.01) and emergency cesarean section during Labor (p<.001).
We found a link between vascular volume injected during Labor and increased risk of neonatal weight loss. Taking this factor into account when monitoring Labor in the birth room is essential to prevent and adapt neonatal management in the event of excessive weight loss. Influence of intrapartum maternal fluids on weight loss in breastfed newborns.
The authors did not see a relationship between higher BMI and IV fluids. This study only included mothers who were ‘low risk’, but they didn’t define what that meant. I would expect that if they included mothers at high risk for a delay in lactation such as those with gestational diabetes, morbid obesity, pre-eclampsia, etc, they would have calculated a higher average weight loss by day 3.
I know that some communities are using the 24 hour weight as the baseline weight; please send us a comment if you are.
We need an increased awareness of this issue among physicians and other providers caring for newborns, particularly in the time of COVID-19, so that infants are not discharged at 24 hours with a recommendation to be supplemented. Perhaps maternal IV fluid administration could become a vital sign in the newborn chart, like the Apgar score. Coupling this with a calculator that could ‘correct’ the weight loss in the first 24 hours may help to reduce the risk of supplementing healthy breastfeeding newborns. The other option is to simply refrain from judging the weight loss in the first 24 hours, and focus on the incremental weight changes from 24-96 hours of life.