Pregnancy is transformative, not just emotionally but physically as well. One of the most common concerns among expectant mothers is weight gain. How much is too much? What’s considered healthy.1 Learn about the factors that contribute to a healthy pregnancy weight gain!
The Role of the Placenta and Uterus in Weight Gain
The placenta, a fascinating organ developed soon after fertilization, supports the growing fetus. By the end of the pregnancy, this organ alone weighs approximately 700g2. Additionally, the muscular wall of the uterus expands, and along with the amniotic fluid, it forms a protective environment for the baby. Together, the baby, the reproductive organs (the uterus and the placenta), and the breast tissue account for nearly half of the recommended added body weight during pregnancy (see table below).3
How Blood Volume and Fluids Contribute to Pregnancy Weight
During pregnancy, a mother’s blood volume increases. This surge caters to the heightened demand for blood in her organs and also serves as nature’s way of preparing for potential blood loss during delivery.3Another common phenomenon towards the end of pregnancy is edema, where the body’s cells absorb excessive water.4 Combined, the increase in fluids is responsible for almost a quarter of the weight gain during pregnancy.3
The Significance of Fat Tissue Accumulation During Pregnancy
Almost a third of the weight gain during pregnancy is attributed to fat tissue. This accumulation of energy is more efficient during pregnancy, ensuring the baby’s proper growth and preparing the body for breastfeeding.5 While this is an advantage when nutrition is scarce, it can become a challenge in societies where energy rich food is available in abundance.
Your Body Mass Index (BMI) before the pregnancy plays a crucial role in determining the recommended weight gain.3 See the table below for guidance. There are several health problems associated with excessive weight gain, e.g. gestational diabetes, pregnancy related hypertension and retention of a higher weight after pregnancy.6
Energy Intake During Pregnancy
Contrary to popular belief, the body doesn’t require a significantly higher energy intake during pregnancy. In the first trimester, just a little extra, equivalent to an additional egg or a slice of whole grain bread daily, suffices. The second trimester demands slightly more, but a banana smoothie would cover it. By the last trimester, an extra bowl of chili con carne or baked salmon with potatoes daily provides the necessary energy.7
In summary, for you and your baby’s health, you should continue with regular physical exercise and healthy food, just a little more than usual.
|BMI before pregnancy||Recommended weight gain|
|<18,5 (Underweight)||12,5 – 18|
|18,5-24,9 (Normal weight)||11,5 – 16|
|25-29,9 (Overweight)||7 – 11,5|
|≥ 30 (Obese)||5-9|
Women’s experience of their pregnancy and postpartum body image: a systematic review and meta-synthesis. BMC Pregnancy and Childbirth. 2014. Volume 330. Hodgkinson E L, Smith D M, Wittkowski
Alterations in physiology and anatomy during pregnancy. Best Practice & Research Clinical Obstetrics and Gynaecology. 2013. Volume 27 (791-802). Tan E K and Tan E L. https://doi.org/10.1016/j.bpobgyn.2013.08.001
Maternal physiology. William’s Obstetrics. 24th edition 2014. Cunningham FG, Leveno KJ, Bloom SL, Spong CY, Dashe JS, Hoffman BL, Casey BM, Sheffield JS et al.
Pregnancy as a window to future health: excessive gestational weight gain and obesity. Seminars in Perinatology. 2015. Volume 39. Gilmore A, Klempel-Donchenko M, Redman L M. https://doi.org/10.1053/j.semperi.2015.05.009
A randomized controlled trial to prevent excessive gestational weight gain and promote postpartum weight loss in overweight and obese women: Health In Pregnancy and Postpartum (HIPP). Contemporary Clinical Trials. 2018. Volume 66 (51-66). Wilcox S, Liu J, Addy C L, Turner-McGrievy G, Burgis J T, Wingard E, Dahl A A, Whitaker K M, Schneider L, Boutté A K https://doi.org/10.1016/j.cct.2018.01.008
Healthy weight gain during pregnancy. EUFIC. 2021. Wep page visited 26.09.2021 https://www.eufic.org/en/healthy-living/article/healthy-weight-gain-during-pregnancy
Gestational Weight Gain: Update on Outcomes and Interventions. Curr Diab Rep. Volume 20. 2020. Champion H L, Harper L M https://doi.org/10.1007/s11892-020-1296-1