Parturition - Symptoms, Stages, and Hormones: Symptoms, Stages, What it is

Parturition Definition

Parturition refers to the delivery of a baby from the uterus and is also known as childbirth. Parturition is a complicated process that is initiated by physiological changes and hormonal signals that prepare the body for labour and birth. Organogenesis completes the development of fetal organs before parturition begins.

Symptoms of Parturition

In the human reproductive system, parturition is the process of childbirth. The Female External Genital Organs play a direct role in childbirth during the final stages of parturition. As labour approaches, the body shows early symptoms of parturition like contractions, water breaking, and cervical changes, helping prepare for the baby's delivery. The symptoms include:

Contractions

• The most important sign of labour is regular, painful contractions of the uterus.

• These contractions help dilate the cervix and push the baby down the birth canal.

Water Breaking

• The "water breaking" is a break in the amniotic sac that starts to drain amniotic fluid.

• This happens either right before labour begins or during.

Cervical Changes

• The cervix becomes softened and eventually starts dilating to prepare for the birth.

• This process can be followed through with prenatal visits.

Back Pain

• Most women get lower back pain from the onset of the realignment of the body in preparation for labour.

• It may feel like a sharp pain or a dull ache.

Blood Emission

• The emission of a small amount of blood or mucus from the vagina may indicate that labour is imminent.

Stages of Parturition

Parturition is the process of childbirth in human reproduction. It happens in three stages—opening of the cervix, delivery of the baby, and removal of the placenta. Parturition has three stages, discussed below :

First Stage

This stage commences with the onset of the contractions and ends when the cervix has dilated to its fullest, which is around 10 cm. It may last for several hours to days, especially for first-time mothers. The first stage can be subdivided into:

• Latent Phase: Early contractions and gradual cervical dilation.

• Active Phase: More intense contractions and rapid dilation.

Second Stage

• This is the stage of birth.

• It commences when the cervix has become fully dilated and concludes with the birth of the baby.

• It may last from some minutes to some hours, depending on previous experience and the position of the baby during delivery.

Third Stage

• This stage occurs following the birth of the baby and involves the expulsion of the placenta.

• It is noted to occur within 30 minutes following delivery and is crucial in ensuring that the uterus contracts well to avoid excessive bleeding.

Hormones in Parturition

Parturition is controlled by special hormones in the body. These hormones help start labour, open the cervix, and push the baby out during childbirth. Parturition is associated with several hormones, which play some critical roles as outlined below:

Oxytocin

• Released by the posterior pituitary gland, oxytocin stimulates uterine contractions and facilitates milk ejection in lactation.

• The levels significantly rise during labour.

Prostaglandins

• These hormones help soften and dilate the cervix, which is important for the passage of the baby through the birth canal.

Relaxin

• This hormone relaxes the pelvic ligaments and prepares the birth canal for birth.

Estrogen and Progesterone

• These hormones regulate the entire process of pregnancy and labour; with the onset of labour, there is an increase in the concentration of oestrogen.

Factors Influencing Parturition

Parturition is affected by different factors. The understanding of factors influencing parturition forms a major part of the Human Reproductive System and how it functions in human growth. These include the mother’s health, the baby’s growth, and the baby’s position in the womb. Some factors are mentioned below:

Gestational Age

• The onset of parturition may depend on the gestation age of the foetus; the normal gestation period is approximately 40 weeks for a full-term pregnancy.

Maternal Health

• The mother's health condition will have an impact on the onset and development of labour.

Fetal Presentation

• The fetal position can also influence the duration and the extent of the difficulty of labour. The presentations in the best position are head-down presentations, also referred to as a vertex presentation.

Clinical Issues During Parturition

Some problems can happen during childbirth due to disorders of the human reproductive system. These disorders may affect pregnancy, labour, or delivery, and need medical care to protect the mother and baby. Some clinical issues are mentioned below:

Monitoring Labour

• Throughout labour, contractions, cervical dilation, and the fetal heart rate are closely monitored for the process to be safe for the mother and the baby.

Pain Management

• Pain can be relieved during labour by epidurals, medication, and some natural methods, such as breathing techniques.

MCQs on Parturition

For NEET Biology, nursing, and physiology exams, MCQs on parturition often focus on

• Symptoms of Parturition
• Stages of Parturition
• Hormonal control
• Clinical importance

Question: Which of these is not an important component of initiation of parturition in humans?

1. Increases in estrogen and progesterone ratio

2. Synthesis of prostaglandins

3. Release of Oxytocin

4. Release of Prolactin

Answer: Increases in estrogen and progesterone ratio are not an important factor for parturition. Estrogen and progesterone levels mark the beginning of the parturition.

While estrogen encourages uterine contractions and gets the uterus ready for labour, progesterone keeps the pregnancy going by preventing it. The ratio of estrogen to progesterone rises as labour draws near helping in the start of parturition and uterine contractions.

Hence, the correct answer is option 1) Increases in estrogen and progesterone ratio.

Question: The signals for parturition originate from:

1. Fully developed foetus only

2. Placenta only

3. Placenta as well as fully developed foetus

4. Oxytocin released from maternal pituitary

Answer: At the time of parturition (childbirth), signals from the fully developed foetus and placenta stimulate the uterus to contract lightly, initiating the process. These uterine contractions send feedback signals to the mother's pituitary gland, which releases the hormone oxytocin. Oxytocin strengthens and intensifies uterine contractions, creating a positive feedback loop that leads to stronger contractions until the baby is delivered. This hormone plays a key role in ensuring the smooth progression of labor and childbirth.

Hence, the correct answer is option 3) Placenta as well as fully developed foetus.

Question: The event in which vigorous contraction of the uterus at the end of pregnancy cause expulsion/delivery of foetus

1. Gestation

2. Conception

3. Parturition

4. Lactation

Answer: Parturition is the process by which the fetus is expelled or delivered after pregnancy due to a strong contraction of the uterus.

Three steps make up the labor process known as parturition:

• Cervical dilatation: The cervix expands to let the fetus pass through.

• Fetal expulsion: The baby is forced through the birth canal and out of the uterus by forceful contractions.

• Placenta delivery: The placenta is discharged following the delivery of the baby.

Hence, the correct answer is option 3) Parturition.

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