Erica Gunderson, PhD, discusses link between lactation and maternal cardiometabolic health

Erica P. Gunderson, PhD, MS, MPH, RD | 2022-2023 March of Dimes Agnes Higgins Award Winner in Maternal-Fetal Nutrition at the Pediatric Academic Societies (PAS) meeting in Washington, DC on April 30, 2023.

Contemporary OB/GYN:

Hi and thank you so much for joining us. I'm Joshua Fitch of Contemporary Pediatrics® and Contemporary OBGYN®.

Erica Gunderson, PhD, MS, MPH, RD:

I'm Dr. Erica Gunderson. I'm a senior research scientist at the Division of Research at Kaiser Permanente Northern California in Oakland, and I'm also professor of Health Systems Sciences at the Bernard Tyson Kaiser Permanente School of Medicine in Pasadena, California.

Contemporary OB/GYN:

Dr. Gunderson, thank you so much for taking the time to join us. First congratulations on receiving the March of Dimes Agnes Higgins Award and maternal fetal nutrition at this year's Pediatric Academic Society's meeting in DC. First, can you just briefly tell us what that means to you?

Gunderson:

I'm so honored to receive the March of Dimes award for Agnes Higgins, maternal fetal nutrition. It means a huge amount to me because of my early career was in public health, nutrition and nutritional sciences. I actually learned about Agnes Higgins and the Montreal diet dispensary, and her work with underprivileged pregnant women were in my training in graduate school. Soshe really inspired me to go into public health as well, and to actually do change move into employment in public health in low income communities. My first job out of graduate school, was with a WIC program in the city of Pasadena Health Department. And of course, Agnes Higgins was her foundational work was the inspiration for the Women, Infants and children's program in the United States that began in the 1960s. So I really feel like I followed in her footsteps in many ways, and from that position, I went to the West Los Angeles premature prevention project, and that was a community public health program in Los Angeles County where I led the nutrition component of that intervention it was into for 5,000 pregnant women, and they were low income and I was the nutritionist as part of the nurse practitioner teams, in clinics that served very low income women, and I went to eight different public health clinics in Los Angeles County every week to provide the new direct nutrition care. So I feel really honored to be given an award with her namesake.

Contemporary OB/GYN: 

Certainly sounds like an amazing story, congratulations once again. Dr. Gunderson. Can you explain to our audience, your lifetime research of this critical link between breastfeeding, gestational diabetes and hypertension on future maternal health, and its relation to childhood obesity? I know a big question.

Gunderson:

Well, there's many parts to the question, I would say, and I think that pregnancy is a challenging, physiologic condition that's imposed upon women. And it results sometimes in complications such as gestational diabetes, and hypertensive disorders of pregnancy. Those occur and about 8% of all women develop gestational diabetes and close to 5 to 10% of women develop hypertensive disorders of pregnancy and both are really important outcomes that not only impact fetal health and development but in the short term and the long-term child health, but they also have lasting impact on the woman herself and her future risk of cardiometabolic diseases. So how does how did these links between these adverse pregnancy outcomes relate to lactation, as well as future cardiovascular health and metabolic health and women? Well, the studies I've been doing have been looking at a continuum a longitudinal continuum, which is is really important for women to understand, which is that the continuum of health starts with pre pregnancy or preconception, metabolic status, metabolic profiles, as well as what happens during pregnancy, and then what after pregnancy, the lactation piece is part of that continuum. So to to obtain optimal health, you really want to prepare for pregnancy and be in the best health you can be before you become pregnant. Then during pregnancy, of course, there are steps to take to to help you have the best outcomes for pregnancy and delivery, and then there's this post-delivery year period or longer, where recovery takes place and we're a lactation is sort of part of the natural continuum to help women recover from the, you know, incredible demands of pregnancy on metabolic and physiologic needs. And those needs are important because you got to transfer nutrients to for optimal field growth and development. But some women adapt their adaptations to those demands that are sometimes result in these pregnancy complications. And we have ways to treat those during pregnancy. But for example, hypertensive disorders, can occur without warning. Sowe're always looking at ways to prevent in ways to improve the pregnancy state. If you have these increases in triglycerides, increases in blood glucose during pregnancy for the woman, increases in blood pressure, and other blood volume that increases the burden on the heart, how do we recover from those? Even if you have not developed any complications, how do women recover from those adverse changes in their metabolic profiles, that are certainly much needed to support good pregnancy outcomes, but how do we recover to the pre pregnancy state that women started out? Lactation seems to offer a lot of advantages in that respect, because the production of milk results in moving these additional lipids and glucose and the decrease in insulin requirements that can help the pancreatic beta cells potentially rest and offload from the earlier demands. So that seems to help the recovery to the prior cardiometabolic profile for women and it also, of course, breastfeeding has tremendous lasting benefits for the child as well.

Contemporary OB/GYN: 

Thank you, Dr. Gunderson. From a diabetes standpoint, what is the benefit of longer breastfeeding, and why is it associated with a 50% lower risk of developing type 2 diabetes?

Gunderson:

So I've been doing prospective longitudinal cohort studies in a multicenter study known as the CARDIA study of black and white women, and it's a 30 year follow up study of young women starting from age 18 to 30. So we, in 30 years, we're going across their entire childbearing life course. So that study is incredible. And it's designed in that it systematically tested women for different cardiometabolic risk factors both before and after the pregnancies as they happen naturally over the lifetime. It has more than one pregnancy for each woman. So those gave us a window in a way to control for differences in risk factors going into pregnancy, and to evaluate as well the pregnancy complication differences so that we could isolate what might be the impact of lactation alone on future diabetes risks. We found up to a 50% relative risk reduction in incidence of type 2 diabetes more than a decade after the last birth and accounting for socioeconomic and behavioral and preconception risk factor profiles. And these were healthy women. So that's the other advantage of following this cohort. And we found this similar finding in a totally different cohort of racially and ethnically diverse women with gestational diabetes that had also longer breastfeeding was associated with up to 50% relative reduction in the two year incidence of type 2 diabetes after pregnancy.

Contemporary OB/GYN: 

Based on your studies, what blood pressure patterns during pregnancy can help identify these patients likely to to develop complications later in their respective pregnancies.

Gunderson:

We published a study in about 175,000 women have diverse racial and ethnic backgrounds that were we looked at the blood pressure measurements that are routinely measured during the first 20 weeks of pregnancies, women come in for care. On average, women had four blood pressures measured in different weeks, from early pregnancy to 20 weeks, and we found six different patterns to those blood pressures, and some blood pressures were modestly elevated, and others were blood pressure changes that were not quite what would be expected, they were slightly increasing over time, instead of decreasing in blood pressure by mid gestation. So these blood pressure patterns were actually quite effective in showing the increasing risk at higher blood pressure patterns, and so that risk increases by six to seven fold with the higher blood pressure levels for preeclampsia, and more than 20 fold, for risk of gestational hypertension. And these are serious disorders of pregnancy that are responsible for much of the morbidity and mortality and during pregnancy in the perinatal period. So we were really interested in going further and looking at how we might do early prediction at an individual level to try to do a better job of either monitoring and ultimately preventing some of these disorders of pregnancy. I think in the future, we're really hopeful that we can determine what sort of risk assessments are needed for women who are pregnant before conception, but also after delivery. What sort of screening can we do for certain women to monitor and help early prevention of diabetes and heart disease and women? I think that we have more work to do with lactation as well, because we don't really know the biological mechanisms. So we need more research to understand that better to truly conclude that what are the specific pathways and the connections? I think, women, you know, we need also, I really think in this venue, we need more support for women. More education before delivery, in terms of what to expect and what if they choose to breastfeed? How can we best support them if we they choose not to, let's also support them well, but we want to basically make the information available but I do think social policy needs to be improved, so that women can recover the best way possible from pregnancy and it's exceedingly intense demands on the physical cardiometabolic profile as well as the physiology and and also to make sure we prevent the severe maternal morbidity and mortality associated with the complications of pregnancy and recognize them not only during delivery, but post delivery as well.