The body mass index (BMI) before pregnancy and gestational weight gain (GWG) may have an association with the outcome of pregnancies. Preeclampsia, gestational diabetes, macrosomia show an association with the BMI. Small-for-gestational age (SGA) infants and preterm births are more seen with mothers with low BMI. Obese women are likely to benefit from low GWG. Both BMI and GWG are closely related to lifestyle, and genetic traits and other medical conditions. Physiologic weight gain in pregnancy is contributed to by the foetus (3.2-3.6 kg), fat deposition (2.7-3.6 kg), increased blood volume (1.4-1.8 kg), increased extravascular fluid volume (0.9-1.4 kg), amniotic fluid volume (0.9 kg), breast enlargement (0.45-1.4 kg), uterine hypertrophy (0..9kg), and placenta (0.7kg).

Glucose intolerance of first onset in pregnancy or first recognition during pregnancy is considered as gestational diabetes mellitus (GDM). GDM is a known risk factor for perinatal complications, and later development of type2 diabetes mellitus. The pregnancy related weight gain can contribute to fat deposition and insulin resistance and it is usually in the second trimester. Insulin resistance is more if there is a rapid or disproportionate increase of weight.
A retrospective analysis of the data collected from 720 pregnant mothers during the period from January 2017 to January 2019 in a tertiary health care centre.
Gestational hypertension was significant in overweight women and those who gained weight above recommended range. (22.4% Vs. 0%; p <0.001).
GDM was noted in a significant percentage of pregnant women within the recommended weight gain group. (12.4% Vs. 0%; p<0.001). Obesity in pregnancy ranges from 1.8% to 25.3%.

In this study, authors had 75 (10.4%) overweight women and 22 (3.1%) obese women. The results show that both obesity and overweight are high-risk factors for gestational hypertension. Study results showed that 78.7% of pre- pregnancy underweight, 4.6% normal weight, and 16.7% overweight had inadequate GWG. All women with normal pre- pregnancy BMI had adequate GWG. Further excessive GWG was seen most in pre-pregnancy overweight women (66.4%) than those with normal weight (30.8%) or underweight (2.8%). GWG was higher in higher BMI groups, showing that overweight and obese women are more likely to have more than recommended GWG. Excessive and inadequate GWG both can lead to adverse pregnancy outcomes. This is echoed by several studies which show that women with weight gain outside the recommended range have a higher incidence of pregnancy complications. The study also showed that excessive weight gain was associated with hypertensive disorders in pregnancy.
About three fourth of the antenatal patients had normal weight gain. All patients with normal BMI had recommended weight gain. Most women with low pre-pregnancy BMI, had low GWG and most women with high BMI had more GWG. Gestational hypertension was associated with high prepregnancy BMI and more than recommended GWG. No mothers with recommended weight gain developedgestational hypertension. Both Women with recommended and less than recommended GWG developed GDM, while no women in more than recommended GWG group had GDM. Pre- pregnancy dietary counselling, physical and lifestyle modifications have a role in bringing down the incidence of gestational diabetes mellitus and gestational hypertension. Efforts should be taken to reduce weight before pregnancy and control excessive GWG during pregnancy to reduce such complications.
Source: Sreelakshmy K and Shahnas M / Indian Journal of Obstetrics and Gynecology Research 2024;11(1):66–69; https://doi.org/10.18231/j.ijogr.2024.012