Routine Weighing During Pregnancy
Routine weighing at each prenatal visit is recommended as standard practice for all pregnant women, regardless of whether medical concerns are present, to monitor gestational weight gain and prevent adverse maternal and fetal outcomes. 1
Why Regular Weighing Matters
The evidence strongly supports routine weight monitoring throughout pregnancy:
Prenatal care providers are advised to evaluate maternal weight at each regularly scheduled prenatal visit to monitor progress toward meeting weight gain goals and provide individualized counseling if significant deviations occur. 1
Nearly 50% of women exceed their weight gain goals, with overweight and obese women having the highest prevalence of excessive weight gain. 1
Excessive gestational weight gain is associated with serious complications including cesarean deliveries, postpartum weight retention, large-for-gestational-age infants, macrosomia, and childhood obesity. 1
Inadequate weight gain carries risks including low birthweight and failure to initiate breastfeeding. 1
The Evidence on Weight Monitoring
Guidelines Support Routine Weighing
Multiple clinical practice guidelines recommend that pregnant women with obesity be informed of the importance of controlling their weight during pregnancy. 2
BMI at first prenatal visit should be used to provide diet and exercise counseling guided by Institute of Medicine (IOM) recommendations. 2
Healthcare professionals need training and support to discuss weight gain with pregnant women, as women expect their maternity care provider to inform them of everything significant in pregnancy. 2
The Problem with Inconsistent Weighing
Inconsistent weighing practices are a major concern identified by both women and midwives, creating barriers to appropriate pregnancy care for women with high BMI. 3
Without discussion about gestational weight gain, women may not think their weight gain is important and may subsequently decline weight management support. 2
Women may seek information elsewhere such as the internet or from family and friends, which may not be accurate or evidence-based. 2
What the Research Shows About Weighing as an Intervention
While weighing alone (without counseling) may not be sufficient:
Weighing as a stand-alone intervention does not reduce excessive gestational weight gain compared to routine antenatal care. 4
However, this does not mean weighing should be abandoned—rather, it means weighing must be combined with appropriate counseling and support. 1
Gestational weight gain is a potentially modifiable risk factor, and diet or exercise interventions during pregnancy can help reduce excessive weight gain when combined with monitoring. 1
Clinical Implementation
What Should Happen at Each Visit
Weight should be measured and documented at every prenatal visit to track progress against IOM guidelines based on pre-pregnancy BMI. 1
Provide diet and exercise counseling at the first prenatal visit based on BMI and IOM recommendations. 5
Target 30 minutes of moderate-intensity exercise daily or 150 minutes per week for pregnant women without contraindications. 5
Regular physical activity during pregnancy reduces risks of gestational diabetes (38% reduction), pre-eclampsia (41% reduction), gestational hypertension (39% reduction), and prenatal depression (67% reduction) without increasing adverse outcomes. 2
Weight Gain Targets by BMI Category
For underweight women (BMI <19.8 kg/m²): Total gain up to 18 kg, with 1.4-2.3 kg in first trimester and 0.5-0.9 kg/week thereafter. 6
For normal weight women: 1.4-2.3 kg in first trimester and 0.5-0.9 kg/week during remainder of pregnancy. 6
For overweight women: Gain at less than 50% of rates recommended for normal weight women. 6
For obese women (BMI >30 kg/m²): Relatively small gain of approximately 7 kg total. 6
Common Pitfalls to Avoid
Do not avoid weighing due to discomfort discussing weight—both women and midwives express reluctance, but this creates barriers to appropriate care. 3
Do not assume obesity alone contraindicates exercise—it does not, and physical activity is beneficial for obese pregnant women. 5
Do not recommend weight loss during pregnancy except in exceptional cases with co-existing medical conditions like diabetes or hypertension requiring intervention. 5
Do not focus only on women with obesity—all women need weight monitoring, including those at risk for inadequate gain. 7
The Bottom Line
The midwife's new practice of not weighing unless there are medical concerns contradicts established guidelines and evidence-based practice. 1 Regular weighing is not just for women with complications—it is a preventive measure to identify and address weight gain issues before they lead to adverse outcomes. 2 The goal is not to shame or stigmatize, but to provide evidence-based monitoring and support for optimal maternal-fetal health outcomes. 2