Labor

For most women, labor causes severe pain and efforts to alleviate the pain are often required.

Pain during labor can be associated with post-traumatic stress disorder.

Postpartum impairment of cognitive function can be mitigated by use of any form of intrapartum analgesia.

Labor pains caused by uterine contractions and cervical dilation.

Epidural analgesia is commonly used as a neuraxial analgesia to provide consistent pain relief throughout labor.

In the United States more than 70% of women who undergo labor or treated with neuraxial and algesia.

Epidural analgesia during labor is generally considered safe for both mother and child.

In a study of 479,178 Danish children, maternal epidural analgesia during labor compared with no epidural analgesia during labor was not significantly associated with autism spectrum disorder in offspring.

In a retrospective Canadian study of 388,254 term singleton children born via vaginal delivery,  the use of epidural analgesic during labor and delivery was significantly associated with a small increase in the risk of autism spectrum disorder in offspring 1.53% in exposed children versus 1.26% in unexposed children.

The second stage of labor is defined as the interval from the complete cervical dilatation to delivery of the fetus.

The second stage of labor is the most physiologically demanding period of labor for both the mother and the fetus.

Prolonged duration of the second stage of labor is associated with adverse maternal and neonatal outcomes.

In a study comparing the effects of immediate versus delayed pushing during the second stage of labor among nulliparous women at or beyond 37 weeks gestation receiving neuraxial analgesia, the primary outcome of spontaneous vaginal delivery with secondary outcomes of maternal and neonatal morbidity: the rate of spontaneous vaginal delivery did not differ between the two groups (Cahill).

Signs of impending labor may include softening of the cervix, dilation and increasing frequency or intensity of contractions.

Labor pains transmitted through visceral sympathetic afferent nerves entering the spinal cord from T10-L1.

Late labor pains associated with perineal stretching transmits pain via the pudendal nerve and sacral nerves S2-S4.

Cortical responses to pain and anxiety related to labor are influenced by the patient’s expectations, preparation foe delivery, emotional support, age, among other factors.

The stress of labor can result in increased corticotropin, cortisol, norepinephrine, beta endorphins, and epinephrine.

Epinephrine elevations can slow labor by causing uterine relaxation.

Stress of labor increases release of catecholamines with increased cardiac output, systemic vascular resistance and oxygen consumption.

Maternal physiologic responses may influence maternal and fetal well being during labor.

Hyperventilation may cause hypocarbia.

Increased metabolic rate may increase oxygen consumption.

Increases in cardiac output and vascular resistance may increase maternal blood pressure.

During labor and delivery abrupt changes in heart rate and blood pressure and fluctuations in intravascular volume stress cardiac function.