From the Guidelines
Third trimester prenatal care should prioritize regular visits, typically every 1-4 weeks, to monitor both maternal and fetal health, with a focus on detecting conditions like preeclampsia, gestational diabetes, and fetal growth restriction. The frequency of visits may vary depending on the country's guidelines, with some countries like France and the Netherlands recommending 7.5 visits, while others like the US recommend 13 visits 1. Key components of third trimester prenatal care include:
- Regular prenatal visits to monitor blood pressure, weight gain, and urine for protein
- Fundal height measurements and fetal heart rate monitoring to track fetal growth and well-being
- Screening tests like the glucose challenge test for gestational diabetes and Group B Streptococcus screening at 36-37 weeks
- Assessment of fetal position through Leopold's maneuvers
- Discussion of labor signs, birth plans, and pain management options
- Daily monitoring of fetal movement using kick counts and reporting decreased movement immediately
- Nutritional guidance with emphasis on adequate hydration, iron intake to prevent anemia, and appropriate weight gain
- Common third trimester medications like prenatal vitamins, iron supplements if anemic, and Rho(D) immune globulin at 28 weeks for Rh-negative mothers
In cases of multiple gestations, like monochorionic twins, closer surveillance may be warranted, with fetal biometry performed every 2-3 weeks and assessment for potential complications like twin-to-twin transfusion syndrome (TTTS) performed weekly 1. However, for low-risk pregnancies, the American Journal of Obstetrics and Gynecology study suggests that guidelines for prenatal care delivery vary across countries, and most countries recommend that low-risk women see only general practitioners or midwives for prenatal care 1.
The most critical aspect of third trimester prenatal care is to identify potential complications early, ensuring the health and safety of both mother and baby during the final weeks of pregnancy and delivery. This can be achieved by following the recommended guidelines and frequency of visits, as well as being aware of the specific needs of multiple gestations or high-risk pregnancies.
From the Research
Key Components of Third Trimester Prenatal Care
The key components of third trimester prenatal care include:
- Regular check-ups with a healthcare provider to monitor the health of the mother and the fetus 2, 3
- Screening for pregnancy complications such as pre-eclampsia, gestational diabetes, and anaemia 4
- Monitoring of fetal growth and wellbeing through ultrasound examinations 5, 6
- Identification and management of obstetric complications 4
- Promotion of health and wellbeing via education and support for nutrition, cessation of substance abuse, uptake of family planning, recognition of danger signs, and birth preparedness 4
Screening and Monitoring
Screening for small for gestational age (SGA) neonates can be performed through sonographic fetal biometry during the third trimester, with a higher performance of screening achieved at 35-37 weeks' gestation 6
- The use of biomarkers such as uterine artery pulsatility index (UtA-PI), umbilical artery PI (UA-PI), fetal middle cerebral artery PI (MCA-PI), maternal serum placental growth factor (PlGF), and soluble fms-like tyrosine kinase-1 (sFLT) can improve the prediction of SGA neonates 6
- Regular ultrasound examinations can help identify potential complications and allow for prompt intervention 5
Antenatal Care Visits
The frequency and timing of antenatal care visits can impact the risk of stillbirth, with reduced antenatal care in the third trimester potentially increasing stillbirth risk 3
- The traditional approach to prenatal care involves visits at regular intervals, with a higher concentration of visits in the third trimester 2
- However, some studies suggest that the traditional pyramid of care should be inverted, with the main emphasis placed in the first rather than third trimester of pregnancy 2