The Relationship Between Fetal Baseline Heart-rate and the Level of Acetyl-choline Esterase in Fetal Blood

Pregnant women between 32-41 weeks' gestation designated for either vaginal birth or cesarean section will be recruited for the study. After signing an informed consent, data regarding maternal resting heart rate and fetal baseline heart rate as depicted on the monitor will be collected.

Patients will be divided into 2 equal groups according to fetal baseline heart rate:

• st group-fetal heart rate between 110-130 beats per minute (bpm).
• nd group-fetal heart rate between 140-160 bpm. A blood sample will be acquired from the parturient and the umbilical cord as well as a sample from the placenta will be obtained. Levels of Acetyl Choline Esterase (AChE) will be determined from all aforementioned samples. Statistical correlation between fetal baseline heart rate and fetal and maternal AChE levels will be assessed.

Data regarding demographic, medical and obstetric information of the participants will be obtained from the hospital's electronic records.

Inclusion criteria

• Pregnant women between 32 and 41 weeks' gestation undergoing either vaginal or cesarean delivery with a fetal baseline heart rate of 110-130 beats per minute and 140-160 beats per minute.

Exclusion criteria

• Delivery before 32 weeks of gestation
• Maternal bradycardic (<60) or tachycardic (>100) resting heart rate.
• Fetal bradycardia (<110) or tachycardia (>160).
• Suspected chorioamnionitis
• Maternal diseases which can affect her heart rate such as:

• Cardiac disease (including arrhythmias)
• Diseases of the thyroid gland
• Rheumatic diseases
• Use of medication which alters heart rate such as:

• Beta blockers
• Beta agonists
• Cocaine, amphetamines
• Use of Pethidine and Phenergan during delivery