Fetal Monitoring in High Risk Pregnancies My research and presentation topic By: Laura Killian

What is normal? Heart beat at 25 days Heart rate before 330 days gestation: 61-85 bpm Heart rate after 330 days gestation: 60-75 bpm Heart rate variations from 40-120 bpm More active than human babies 20 complex movements per hour Dormant up to 10 minutes Calm periods for 30-60 minutes Maximum amniotic fluid depth .8-14.9cm, averaging 7.9cm Maximum allantoic fluid depth 4.7-22.1cm, averaging 13.4cm Aortic diameter averages 22.8mm Uteroplacental thickness of 7-13mm, averaging 11.5mm First must establish what is normal in order to recognize complications and abnormalities For example, heart rate: As low as 40 bpm at rest or when maximizing efficiency As high as 120 bpm when active repositioning Activity proves there is adequate oxygen supply If heart rate is very high or low recheck in 24 hours A very high heart rate indicates stress Variations between extremes indicate compensation for lack of oxygen If movement complexity of movements decreases, it may indicate impaired oxygen supply If volume of fluid is greater, it may mean there is a fetal hemorrhage or diarrhea If diameter is small, it may mean inadequate nutrient and oxygen to support growth and development If thicker, may indicate placentitis

High Risk Pregnancy Defined: “A mare that has had a septic foal in the past, or a dystocia, or has had a history of premature placental separation or red bag” What is a high risk pregnancy?

Perinatology Defined: “Care of the mother and fetus during pregnancy, labor, delivery, and early neonatal period, particularly when the mother and/or fetus are at high risk for complications” What is a high risk pregnancy?

Why fetal Monitoring? Check physiological signs for normal development Indicate that a problem has arisen and asses severity Address issues before they become too serious Monitor response to treatment Decrease the chance of abortion or death of foal Decrease chance of injury or death of mare Why is it important? Cover more in depth during upcoming slides

Fetal Biophysical Profile Humans Horses Fetal Heart Rate Body Movement Amniotic Fluid Breathing Body Tone Fetal Heart Rate Fetal Activity Amniotic Fluid Allantoic Fluid Fetal Aortic Diameter Placenta Thickness Uteroplacental Contact Check physiological signs for normal development No scale for biophysical profile in horses, like in humans although studies have created guides for measurement Set factors typically observed, but not precise and standard calculation of risk Heart rate shows stress and movement Activity indicated adequate oxygen and use of central nervous system Fluid volume shows fluid formation and excretion proving oxygen sufficiency. Aortic diameter predicts final size of foal Placenta thickening indicating potential infection Uteroplacental contact shows effectiveness of nutrient transfer from mare to fetus

When to closely monitor Previous Pregnancies Current Pregnancy Red bags Dystocia abortion Premature foaling Prolonged pregnancy Uterine hemorrhage Neonatal isoerythrolysis Retained placenta Lack of milk production placentitis Twins illness weight loss Surgery Anesthesia stress Grazing on tall fescue Infection Vaginal discharge Fever Umbilical torsion Prevalence of problem and need for advancement Numerous reasons why a mare would be high risk and need careful assessment and monitoring Must check physiological signs for normal development in current pregnancy to find potential issues Total number of high risk mares not available because of the variances between level of severity and numerous causes Birthing complications are the second most common cause of fetal loss

Foalert System Sutured onto mare’s vulva Signal transmitted to indicate parturition Does not require veterinarian Enables assistant to monitor delivery All of the following techniques and technology decrease the chance of abortion or death of foal and/or injury or death in the mare Foalert is a simple way to inform attendants of foaling so someone is present in case of complications

Hormone Levels Less sensitive than ultrasound Blood samplings check progesterone and estrogen levels High progesterone in the mid-stage of pregnancy may indicate placentitis, stress or other complications Low estrogen levels indicate the fetus may not be viable Numerous samples must be taken throughout the pregnancy to accurately assess risk Progesterone levels and estrogen levels may indicate issues maintain the pregnancy or carrying to term

Ultrasonography Used in early pregnancy Used after 90 days Rectal Abdominal Used in early pregnancy Tightness of cervix Position on foal Size of uterus Movement of foal Used after 90 days Heart rate patterns Umbilical chord Amniotic fluid Fetal aorta Detects heart beat in early ultrasound Shows changes of position, indication viability and health of foal After 90 days, the foal descends further into the abdomen Heart Rate data is more details with abdominal ultrasound Umbilical chords are the nutrient link between the mare and fetus Amniotic fluid (cups???) Fetal aorta size can be used to estimate foals overall size

Doppler Monitor Attached to the exterior of the mare’s abdomen Tracks fetal movement and heart rate Keeps record of variations for several hours at a time Give more accurate minute by minute changes and patterns in heart rate Not used except in animal hospitals with round the clock monitoring despite that it is inexpensive and simple

Intranasal Oxygen Foal oxygen therapy Maternal oxygen therapy Foals receptors can be damaged an unresponsive to the low levels of oxygen Other foals are too weak or fatigued to respond to lack of oxygen The last type of foal to receive this therapy has upper airway obstruction In mares, the oxygen therapy is given to support the fetus when lacking intake

Effectiveness Neonatal Intensive Care Unit at New Bolton Center 1990-2005 2053 cases 84% success rate 8-10% of broodmares lose their pregnancy before term “Vast numbers of normal pregnancies can lull us into a false sense of security” Diagnosis for success High risk pregnancies happen for many reasons, but still are not occurring extremely frequently If issues are detected early, the pregnancy can typically be stabilized With current technology available, veterinary hospitals have a high success rate in saving the mares and foals

Services and Fees Standard Ultrasounds examinations ($50-$65/exam) Monitoring, medication and evaluations (additional fee) Pregnant Mare boarding ($20-$30/day) Broodmare Monitoring ($500-$750/foaling) Doppler Monitoring (rentals for $20-$50/month) High Risk Pregnant Mare Program (price not disclosed) Cesarean section ($3000+/operation) Places where it’s done/price Ultrasounds are used to check pregnancy status, twinning and development Monitoring may be needed if the mare has had previous complications Medication may be needed to regulate hormone levels (progesterone) Additional evaluations may be made if the heart rate is at an extreme Daily monitoring is done through in-stall cameras and post-natal care provided Doppler monitors tracks changes in heart rate and movement Mare programs provide round the clock monitoring, surgical stall and advanced monitoring and examination equipment Emergency C sections can save the mare and foal

Questions?