Lecture Notes: Final Weeks of Pregnancy and Childbirth

Fetal Development in Final Weeks

• Continued weight gain and body fat accumulation.
• Uterus expands, leading to increased discomfort for the mother (lower back, pelvis, abdomen).
• Baby may change positions in preparation for birth:
  • Commonly settles into cephalic presentation (head-down position).
  • This position relieves diaphragm pressure, aiding maternal breathing but increases bladder pressure (more frequent urination).

Lung Development

• Lungs continue to mature, producing a substance that keeps air sacs open for oxygen exchange.
• Baby practices breathing movements, which involve rhythmic contractions of diaphragm and chest muscles.

Maternal Emotions and Nesting Instinct

• A range of emotions may occur before labor: excitement, anxiety, nervousness.
• Nesting instinct: urge to clean and prepare for the baby's arrival.

Braxton Hicks and True Labor Contractions

• Braxton Hicks contractions: practice contractions that may start in the second trimester but become noticeable later.
• True labor contractions: have a regular pattern; become more frequent, longer, and intense, leading to cervical dilation.

Amniotic Sac and Labor Process

• Rupture of the amniotic sac: can happen naturally or be done by a healthcare provider (amniotomy).
• Relaxin hormone: softens and loosens ligaments and tissues in the pelvic area for childbirth.

Cervical Changes and Delivery

• Cervix undergoes changes: softens, thins, and dilates (measured in centimeters; 10 cm = full dilation).
• Once fully dilated, mother enters the pushing stage:
  • Actively pushes during contractions to move the baby through the birth canal.
  • Vaginal walls stretch to accommodate the baby's size.
  • Episiotomy: surgical cut in the perineum, performed if necessary to prevent tearing (not routine).

Birth Process

• Baby emerges with head first, followed by the body; shoulders rotate to align with pelvic outlet.
• Post-birth transition: respiratory system changes as baby starts breathing air; cord clamped and cut after pulsating stops.
• Continued contractions to deliver the placenta, typically shorter and less intense than labor stages.

Conclusion

• Monitor the baby's condition after birth, including vital signs, weight, and overall well-being.